Bump to 4.5.2

Co-authored-by: Raphael Michel <michel@rami.io>

.github/dependabot.yml

@@ -0,0 +1,15 @@
+# To get started with Dependabot version updates, you'll need to specify which
+# package ecosystems to update and where the package manifests are located.
+# Please see the documentation for all configuration options:
+# https://help.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+
+version: 2
+updates:
+  - package-ecosystem: "pip"
+    directory: "/src"
+    schedule:
+      interval: "daily"
+  - package-ecosystem: "npm"
+    directory: "/src/pretix/static/npm_dir"
+    schedule:
+      interval: "monthly"

.gitlab-ci.yml

@@ -5,8 +5,8 @@ tests:
         - virtualenv env
         - source env/bin/activate
         - pip install -U pip wheel setuptools
-        - XDG_CACHE_HOME=/cache pip3 install -r src/requirements.txt --no-use-pep517 -Ur src/requirements/dev.txt
         - cd src
+        - XDG_CACHE_HOME=/cache pip3 install -e ".[dev]"
         - python manage.py check
         - make all compress
         - py.test --reruns 3 -n 3 tests
@@ -21,8 +21,8 @@ pypi:
         - virtualenv env
         - source env/bin/activate
         - pip install -U pip wheel setuptools check-manifest twine
-        - XDG_CACHE_HOME=/cache pip3 install -Ur src/requirements.txt -r src/requirements/dev.txt
         - cd src
+        - XDG_CACHE_HOME=/cache pip3 install -e ".[dev]"
         - python setup.py sdist
         - pip install dist/pretix-*.tar.gz
         - python -m pretix migrate

Dockerfile

@@ -1,9 +1,9 @@
-FROM python:3.8
+FROM python:3.9-bullseye
 
 RUN apt-get update && \
     apt-get install -y --no-install-recommends \
             build-essential \
-            default-libmysqlclient-dev \
+            libmariadb-dev \
             gettext \
             git \
             libffi-dev \
@@ -15,8 +15,7 @@ RUN apt-get update && \
             libxslt1-dev \
             locales \
             nginx \
-            python-dev \
-            python-virtualenv \
+            python3-virtualenv \
             python3-dev \
             sudo \
             supervisor \
@@ -57,10 +56,11 @@ COPY deployment/docker/supervisord /etc/supervisord
 COPY deployment/docker/supervisord.all.conf /etc/supervisord.all.conf
 COPY deployment/docker/supervisord.web.conf /etc/supervisord.web.conf
 COPY deployment/docker/nginx.conf /etc/nginx/nginx.conf
+COPY deployment/docker/nginx-max-body-size.conf /etc/nginx/conf.d/nginx-max-body-size.conf
 COPY deployment/docker/production_settings.py /pretix/src/production_settings.py
 COPY src /pretix/src
 
-RUN cd /pretix/src && pip3 install .
+RUN cd /pretix/src && python setup.py install
 
 RUN chmod +x /usr/local/bin/pretix && \
     rm /etc/nginx/sites-enabled/default && \

deployment/docker/nginx-max-body-size.conf

@@ -0,0 +1 @@
+client_max_body_size 100M;

deployment/docker/nginx.conf

@@ -16,7 +16,6 @@ http {
 	charset utf-8;
 	tcp_nopush on;
 	tcp_nodelay on;
-	client_max_body_size 100M;
 
 	log_format private '[$time_local] $host "$request" $status $body_bytes_sent';
 
@@ -66,9 +65,18 @@ http {
             access_log off;
             expires 365d;
             add_header Cache-Control "public";
+            add_header Access-Control-Allow-Origin "*";
+            gzip on;
         }
         location / {
-            proxy_pass http://unix:/tmp/pretix.sock:/;
+            # Very important:
+            #   proxy_pass http://unix:/tmp/pretix.sock:;
+            # is not the same as
+            #   proxy_pass http://unix:/tmp/pretix.sock:/;
+            # In the latter case, nginx will apply its URL parsing, in the former it doesn't.
+            # There are situations in which pretix' API will deal with "file names" containing %2F%2F, which
+            # nginx will normalize to %2F, which can break ticket validation.
+            proxy_pass http://unix:/tmp/pretix.sock:;
             proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
         	proxy_set_header Host $http_host;
         }

doc/admin/config.rst

@@ -434,3 +434,19 @@ pretix can make use of some external tools if they are installed. Currently, the
 
 .. _Python documentation: https://docs.python.org/3/library/configparser.html?highlight=configparser#supported-ini-file-structure
 .. _Celery documentation: http://docs.celeryproject.org/en/latest/userguide/configuration.html
+
+Maximum upload file sizes
+-------------------------
+
+You can configure the maximum file size for uploading various files::
+
+    [pretix_file_upload]
+    ; Max upload size for images in MiB, defaults to 10 MiB
+    max_size_image = 12
+    ; Max upload size for favicons in MiB, defaults to 1 MiB
+    max_size_favicon = 2
+    ; Max upload size for email attachments in MiB, defaults to 10 MiB
+    max_size_email_attachment = 15
+    ; Max upload size for other files in MiB, defaults to 10 MiB
+    ; This includes all file upload type order questions
+    max_size_other = 100

doc/admin/errors.rst

@@ -0,0 +1,40 @@
+.. _`admin-errors`:
+
+Dealing with errors
+===================
+
+If you encounter an error in pretix, please follow the following steps to debug it:
+
+* If the error message is shown on a **white page** and the last line of the error includes "nginx", the error is not with pretix
+  directly but with your nginx webserver. This might mean that pretix is not running, but it could also be something else.
+  Please first check your nginx error log. The default location is ``/var/log/nginx/error.log``.
+
+  * If it turns out pretix is not running, check the output of ``docker logs pretix`` for a docker installation and
+    ``journalctl -u pretix-web.service`` for a manual installation.
+
+* If the error message is an "**Internal Server Error**" in purple pretix design, please check pretix' log file which by default is at
+  ``/var/pretix-data/logs/pretix.log`` if you installed with docker and ``/var/pretix/data/logs/pretix.log`` otherwise. If you don't
+  know how to interpret it, open a discussion on GitHub with the relevant parts of the log file.
+
+  * If the error message includes ``/usr/bin/env: ‘node’: No such file or directory``, you forgot to install ``node.js``
+
+  * If the error message includes ``OfflineGenerationError``, you might have forgot to run the ``rebuild`` step after a pretix update
+    or plugin installation.
+
+  * If the error message mentions your database server or redis server, make sure these are running and accessible.
+
+* If pretix loads fine but certain actions (creating carts, orders, or exports, downloading tickets, sending emails) **take forever**,
+  ``pretix-worker`` is not running. Check the output of ``docker logs pretix`` for a docker installation and
+  ``journalctl -u pretix-worker.service`` for a manual installation.
+
+* If the page loads but all **styles are missing**, you probably forgot to update your nginx configuration file after an upgrade of your
+  operating system's python version.
+
+
+If you are unable to debug the issue any further, please open a **discussion** on GitHub in our `Q&A Forum`_. Do **not** open an issue
+right away, since most things turn out not to be a bug in pretix but a mistake in your server configuration. Make sure to include
+relevant log excerpts in your question.
+
+If you're a pretix Enterprise customer, you can also reach out to support@pretix.eu with your issue right away.
+
+.. _Q&A Forum: https://github.com/pretix/pretix/discussions/categories/q-a

doc/admin/index.rst

@@ -9,7 +9,9 @@ This documentation is for everyone who wants to install pretix on a server.
    :maxdepth: 2
 
    installation/index
+   updates
    config
    maintainance
    scaling
+   errors
    indexes

doc/admin/indexes.rst

@@ -50,7 +50,7 @@ Here is the currently recommended set of commands::
     CREATE INDEX CONCURRENTLY pretix_addidx_orderpos_name
         ON pretixbase_orderposition
         USING gin (upper("attendee_name_cached") gin_trgm_ops);
-    CREATE INDEX CONCURRENTLY pretix_addidx_orderpos_scret
+    CREATE INDEX CONCURRENTLY pretix_addidx_orderpos_secret
         ON pretixbase_orderposition
         USING gin (upper("secret") gin_trgm_ops);
     CREATE INDEX CONCURRENTLY pretix_addidx_orderpos_email

doc/admin/installation/docker_smallscale.rst

@@ -39,6 +39,10 @@ Linux and firewalls, we recommend that you start with `ufw`_.
 .. warning:: We recommend **PostgreSQL**. If you go for MySQL, make sure you run **MySQL 5.7 or newer** or
              **MariaDB 10.2.7 or newer**.
 
+.. warning:: By default, using `ufw` in conjunction will not have any effect. Please make sure to either bind the exposed
+             ports of your docker container explicitly to 127.0.0.1 or configure docker to respect any set up firewall
+             rules.
+
 On this guide
 -------------
 
@@ -183,7 +187,7 @@ named ``/etc/systemd/system/pretix.service`` with the following content::
     TimeoutStartSec=0
     ExecStartPre=-/usr/bin/docker kill %n
     ExecStartPre=-/usr/bin/docker rm %n
-    ExecStart=/usr/bin/docker run --name %n -p 8345:80 \
+    ExecStart=/usr/bin/docker run --name %n -p 127.0.0.1:8345:80 \
         -v /var/pretix-data:/data \
         -v /etc/pretix:/etc/pretix \
         -v /var/run/redis:/var/run/redis \
@@ -233,7 +237,7 @@ The following snippet is an example on how to configure a nginx proxy for pretix
         ssl_certificate_key /path/to/key.pem;
 
         location / {
-            proxy_pass http://localhost:8345/;
+            proxy_pass http://localhost:8345;
             proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
             proxy_set_header X-Forwarded-Proto https;
             proxy_set_header Host $http_host;
@@ -252,6 +256,8 @@ create an event and start selling tickets!
 
 You should probably read :ref:`maintainance` next.
 
+.. _`docker_updates`:
+
 Updates
 -------
 
@@ -267,6 +273,8 @@ Restarting the service can take a few seconds, especially if the update requires
 Replace ``stable`` above with a specific version number like ``1.0`` or with ``latest`` for the development
 version, if you want to.
 
+Make sure to also read :ref:`update_notes` and the release notes of the version you are updating to.
+
 .. _`docker_plugininstall`:
 
 Install a plugin

doc/admin/installation/manual_smallscale.rst

@@ -25,7 +25,7 @@ installation guides):
 * A HTTP reverse proxy, e.g. `nginx`_ or Apache to allow HTTPS connections
 * A `PostgreSQL`_ 9.6+, `MySQL`_ 5.7+, or MariaDB 10.2.7+ database server
 * A `redis`_ server
-* A `nodejs_` installation
+* A `nodejs`_ installation
 
 We also recommend that you use a firewall, although this is not a pretix-specific recommendation. If you're new to
 Linux and firewalls, we recommend that you start with `ufw`_.
@@ -72,7 +72,7 @@ To build and run pretix, you will need the following debian packages::
 
     # apt-get install git build-essential python-dev python3-venv python3 python3-pip \
                       python3-dev libxml2-dev libxslt1-dev libffi-dev zlib1g-dev libssl-dev \
-                      gettext libpq-dev libmariadbclient-dev libjpeg-dev libopenjp2-7-dev
+                      gettext libpq-dev libmariadb-dev libjpeg-dev libopenjp2-7-dev
 
 Config file
 -----------
@@ -237,7 +237,7 @@ The following snippet is an example on how to configure a nginx proxy for pretix
         add_header X-Content-Type-Options nosniff;
 
         location / {
-            proxy_pass http://localhost:8345/;
+            proxy_pass http://localhost:8345;
             proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
             proxy_set_header X-Forwarded-Proto https;
             proxy_set_header Host $http_host;
@@ -280,13 +280,14 @@ create an event and start selling tickets!
 
 You should probably read :ref:`maintainance` next.
 
+.. _`manual_updates`:
+
 Updates
 -------
 
 .. warning:: While we try hard not to break things, **please perform a backup before every upgrade**.
 
-To upgrade to a new pretix release, pull the latest code changes and run the following commands (again, replace
-``postgres`` with ``mysql`` if necessary)::
+To upgrade to a new pretix release, pull the latest code changes and run the following commands::
 
     $ source /var/pretix/venv/bin/activate
     (venv)$ pip3 install -U --upgrade-strategy eager pretix gunicorn
@@ -295,6 +296,7 @@ To upgrade to a new pretix release, pull the latest code changes and run the fol
     (venv)$ python -m pretix updatestyles
     # systemctl restart pretix-web pretix-worker
 
+Make sure to also read :ref:`update_notes` and the release notes of the version you are updating to.
 
 .. _`manual_plugininstall`:
 

doc/admin/maintainance.rst

@@ -9,6 +9,8 @@ If you host your own pretix instance, you also need to care about the availabili
 of your service and the safety of your data yourself. This page gives you some
 information that you might need to do so properly.
 
+.. _`backups`:
+
 Backups
 -------
 

doc/admin/updates.rst

@@ -0,0 +1,51 @@
+.. _`update_notes`:
+
+Update notes
+============
+
+pretix receives regular feature and bugfix updates and we highly encourage you to always update to
+the latest version for maximum quality and security. Updates are announces on our `blog`_. There are
+usually 10 feature updates in a year, so you can expect a new release almost every month.
+
+Pure bugfix releases are only issued in case of very critical bugs or security vulnerabilities. In these
+case, we'll publish bugfix releases for the last three stable release branches.
+
+Compatibility to plugins and in very rare cases API clients may break. For in-depth details on the
+API changes of every version, please refer to the release notes published on our blog.
+
+Upgrade steps
+-------------
+
+For the actual upgrade, you can usually just follow the steps from the installation guide for :ref:`manual installations <manual_updates>`
+or :ref:`docker installations <docker_updates>` respectively.
+Generally, it is always strongly recommended to perform a :ref:`backup <backups>` first.
+It is possible to skip versions during updates, although we recommend not skipping over major version numbers
+(i.e. if you want to go from 2.4 to 4.4, first upgrade to 3.0, then upgrade to 4.0, then to 4.4).
+
+In addition to these standard update steps, the following list issues steps that should be taken when you upgrade
+to specific versions for pretix. If you're skipping versions, please read the instructions for every version in
+between as well.
+
+Upgrade to 3.17.0 or newer
+""""""""""""""""""""""""""
+
+pretix 3.17 introduces a dependency on ``nodejs``, so you should install it on your system::
+
+    # apt install nodejs npm
+
+Upgrade to 4.4.0 or newer
+"""""""""""""""""""""""""
+
+pretix 4.4 introduces a new data structure to store historical financial data. If you already have existing
+data in your database, you will need to back-fill this data or you might get incorrect reports! This is not
+done automatically as part of the usual update steps since it can take a while on large databases and you might
+want to do it in parallel while the system is already running again. Please execute the following command::
+
+    (venv)$ python -m pretix create_order_transactions
+
+Or, with a docker installation::
+
+    $ docker exec -it pretix.service pretix create_order_transactions
+
+
+.. _blog: https://pretix.eu/about/en/blog/

doc/api/fundamentals.rst

@@ -87,7 +87,8 @@ respectively, or ``null`` if there is no such page. You can use those URLs to re
 respective page.
 
 The field ``results`` contains a list of objects representing the first results. For most
-objects, every page contains 50 results.
+objects, every page contains 50 results. You can specify a lower pagination size using the
+``page_size`` query parameter, but no more than 50.
 
 Conditional fetching
 --------------------

doc/api/resources/carts.rst

@@ -243,6 +243,99 @@ Cart position endpoints
    :statuscode 403: The requested organizer/event does not exist **or** you have no permission to create this
          order.
 
+.. http:post:: /api/v1/organizers/(organizer)/events/(event)/cartpositions/bulk_create/
+
+   Creates multiple new cart position. This operation is deliberately not atomic, so each cart position can succeed
+   or fail individually, so the response code of the response is not the only thing to look at!
+
+   .. warning:: This endpoint is considered **experimental**. It might change at any time without prior notice.
+
+   .. warning:: The same limitations as with the regular creation endpoint apply.
+
+   **Example request**:
+
+   .. sourcecode:: http
+
+      POST /api/v1/organizers/bigevents/events/sampleconf/cartpositions/bulk_create/ HTTP/1.1
+      Host: pretix.eu
+      Accept: application/json, text/javascript
+      Content-Type: application/json
+
+      [
+        {
+          "item": 1,
+          "variation": null,
+          "price": "23.00",
+          "attendee_name_parts": {
+            "given_name": "Peter",
+            "family_name": "Miller"
+          },
+          "attendee_email": null,
+          "answers": [
+            {
+              "question": 1,
+              "answer": "23",
+              "options": []
+            }
+          ],
+          "subevent": null
+        },
+        {
+          "item": 1,
+          "variation": null,
+          "price": "23.00",
+          "attendee_name_parts": {
+            "given_name": "Maria",
+            "family_name": "Miller"
+          },
+          "attendee_email": null,
+          "answers": [
+            {
+              "question": 1,
+              "answer": "23",
+              "options": []
+            }
+          ],
+          "subevent": null
+        }
+      ]
+
+   **Example response**:
+
+   .. sourcecode:: http
+
+      HTTP/1.1 200 OK
+      Vary: Accept
+      Content-Type: application/json
+
+      {
+        "results": [
+          {
+            "success": true,
+            "errors": null,
+            "data": {
+              "id": 1,
+              ...
+            },
+          },
+          {
+            "success": "false",
+            "errors": {
+              "non_field_errors": ["There is not enough quota available on quota \"Tickets\" to perform the operation."]
+            },
+            "data": null
+          }
+        ]
+      }
+
+   :param organizer: The ``slug`` field of the organizer of the event to create positions for
+   :param event: The ``slug`` field of the event to create positions for
+   :statuscode 200: See response for success
+   :statuscode 400: Your input could not be parsed
+   :statuscode 401: Authentication failure
+   :statuscode 403: The requested organizer/event does not exist **or** you have no permission to create this
+         order.
+
 .. http:delete:: /api/v1/organizers/(organizer)/events/(event)/cartpositions/(id)/
 
    Deletes a cart position, identified by its internal ID.

doc/api/resources/checkinlists.rst

@@ -604,6 +604,8 @@ Order position endpoints
    :statuscode 403: The requested organizer/event does not exist **or** you have no permission to view this resource.
    :statuscode 404: The requested order position or check-in list does not exist.
 
+.. _`rest-checkin-redeem`:
+
 .. http:post:: /api/v1/organizers/(organizer)/events/(event)/checkinlists/(list)/positions/(id)/redeem/
 
    Tries to redeem an order position, identified by its internal ID, i.e. checks the attendee in. This endpoint
@@ -618,8 +620,9 @@ Order position endpoints
    :<json boolean canceled_supported: When this parameter is set to ``true``, the response code ``canceled`` may be
                                       returned. Otherwise, canceled orders will return ``unpaid``.
    :<json datetime datetime: Specifies the datetime of the check-in. If not supplied, the current time will be used.
-   :<json boolean force: Specifies that the check-in should succeed regardless of previous check-ins or required
-                         questions that have not been filled. Defaults to ``false``.
+   :<json boolean force: Specifies that the check-in should succeed regardless of revoked barcode, previous check-ins or required
+                         questions that have not been filled. This is usually used to upload offline scans that already happened,
+                         because there's no point in validating them since they happened whether they are valid or not. Defaults to ``false``.
    :<json string type: Send ``"exit"`` for an exit and ``"entry"`` (default) for an entry.
    :<json boolean ignore_unpaid: Specifies that the check-in should succeed even if the order is in pending state.
                                  Defaults to ``false`` and only works when ``include_pending`` is set on the check-in

doc/api/resources/index.rst

@@ -31,5 +31,6 @@ Resources and endpoints
    webhooks
    seatingplans
    exporters
+   sendmail_rules
    billing_invoices
    billing_var

doc/api/resources/invoices.rst

@@ -78,6 +78,12 @@ lines                                 list of objects            The actual invo
                                                                  an event series not created by a product (e.g. shipping or
                                                                  cancellation fees) as well as whenever the respective (sub)event
                                                                  has no end date set.
+├ event_location                      string                     Location of the (sub)event this line was created for as it
+                                                                 was set during invoice creation. Can be ``null`` for all invoice
+                                                                 lines created before this was introduced as well as for lines in
+                                                                 an event series not created by a product (e.g. shipping or
+                                                                 cancellation fees) as well as whenever the respective (sub)event
+                                                                 has no location set.
 ├ attendee_name                       string                     Attendee name at time of invoice creation. Can be ``null`` if no
                                                                  name was set or if names are configured to not be added to invoices.
 ├ gross_value                         money (string)             Price including taxes
@@ -110,6 +116,10 @@ internal_reference                    string                     Customer's refe
 
    The attributes ``fee_type`` and ``fee_internal_type`` have been added.
 
+.. versionchanged:: 4.1
+
+   The attribute ``lines.event_location`` has been added.
+
 
 Endpoints
 ---------
@@ -179,6 +189,7 @@ Endpoints
                 "fee_internal_type": null,
                 "event_date_from": "2017-12-27T10:00:00Z",
                 "event_date_to": null,
+                "event_location": "Heidelberg",
                 "attendee_name": null,
                 "gross_value": "23.00",
                 "tax_value": "0.00",
@@ -267,6 +278,7 @@ Endpoints
             "fee_internal_type": null,
             "event_date_from": "2017-12-27T10:00:00Z",
             "event_date_to": null,
+            "event_location": "Heidelberg",
             "attendee_name": null,
             "gross_value": "23.00",
             "tax_value": "0.00",

doc/api/resources/item_variations.rst

@@ -25,7 +25,21 @@ description                           multi-lingual string       A public descri
                                                                  Markdown syntax or can be ``null``.
 position                              integer                    An integer, used for sorting
 require_membership                    boolean                    If ``true``, booking this variation requires an active membership.
+require_membership_hidden             boolean                    If ``true`` and ``require_membership`` is set, this variation will
+                                                                 be hidden from users without a valid membership.
 require_membership_types              list of integers           Internal IDs of membership types valid if ``require_membership`` is ``true``
+sales_channels                        list of strings            Sales channels this variation is available on, such as
+                                                                 ``"web"`` or ``"resellers"``. Defaults to all existing sales channels.
+                                                                 The item-level list takes precedence, i.e. a sales
+                                                                 channel needs to be on both lists for the item to be
+                                                                 available.
+available_from                        datetime                   The first date time at which this variation can be bought
+                                                                 (or ``null``).
+available_until                       datetime                   The last date time at which this variation can be bought
+                                                                 (or ``null``).
+hide_without_voucher                  boolean                    If ``true``, this variation is only shown during the voucher
+                                                                 redemption process, but not in the normal shop
+                                                                 frontend.
 ===================================== ========================== =======================================================
 
 Endpoints
@@ -63,7 +77,12 @@ Endpoints
             },
             "active": true,
             "require_membership": false,
+            "require_membership_hidden": false,
             "require_membership_types": [],
+            "sales_channels": ["web"],
+            "available_from": null,
+            "available_until": null,
+            "hide_without_voucher": false,
             "description": {
               "en": "Test2"
             },
@@ -79,6 +98,7 @@ Endpoints
             },
             "active": true,
             "require_membership": false,
+            "require_membership_hidden": false,
             "require_membership_types": [],
             "description": {},
             "position": 1,
@@ -128,7 +148,12 @@ Endpoints
         "original_price": null,
         "active": true,
         "require_membership": false,
+        "require_membership_hidden": false,
         "require_membership_types": [],
+        "sales_channels": ["web"],
+        "available_from": null,
+        "available_until": null,
+        "hide_without_voucher": false,
         "description": null,
         "position": 0
       }
@@ -159,7 +184,12 @@ Endpoints
         "default_price": "10.00",
         "active": true,
         "require_membership": false,
+        "require_membership_hidden": false,
         "require_membership_types": [],
+        "sales_channels": ["web"],
+        "available_from": null,
+        "available_until": null,
+        "hide_without_voucher": false,
         "description": null,
         "position": 0
       }
@@ -180,7 +210,12 @@ Endpoints
         "original_price": null,
         "active": true,
         "require_membership": false,
+        "require_membership_hidden": false,
         "require_membership_types": [],
+        "sales_channels": ["web"],
+        "available_from": null,
+        "available_until": null,
+        "hide_without_voucher": false,
         "description": null,
         "position": 0
       }
@@ -232,7 +267,12 @@ Endpoints
         "original_price": null,
         "active": false,
         "require_membership": false,
+        "require_membership_hidden": false,
         "require_membership_types": [],
+        "sales_channels": ["web"],
+        "available_from": null,
+        "available_until": null,
+        "hide_without_voucher": false,
         "description": null,
         "position": 1
       }

doc/api/resources/items.rst

@@ -70,6 +70,8 @@ require_approval                      boolean                    If ``true``, or
                                                                  paid.
 require_bundling                      boolean                    If ``true``, this item is only available as part of bundles.
 require_membership                    boolean                    If ``true``, booking this item requires an active membership.
+require_membership_hidden             boolean                    If ``true`` and ``require_membership`` is set, this product will
+                                                                 be hidden from users without a valid membership.
 require_membership_types              list of integers           Internal IDs of membership types valid if ``require_membership`` is ``true``
 grant_membership_type                 integer                    If set to the internal ID of a membership type, purchasing this item will
                                                                  create a membership of the given type.
@@ -105,8 +107,22 @@ variations                            list of objects            A list with one
 ├ active                              boolean                    If ``false``, this variation will not be sold or shown.
 ├ description                         multi-lingual string       A public description of the variation. May contain
 ├ require_membership                  boolean                    If ``true``, booking this variation requires an active membership.
+├ require_membership_hidden           boolean                    If ``true`` and ``require_membership`` is set, this variation will
+                                                                 be hidden from users without a valid membership.
 ├ require_membership_types            list of integers           Internal IDs of membership types valid if ``require_membership`` is ``true``
                                                                  Markdown syntax or can be ``null``.
+├ sales_channels                      list of strings            Sales channels this variation is available on, such as
+                                                                 ``"web"`` or ``"resellers"``. Defaults to all existing sales channels.
+                                                                 The item-level list takes precedence, i.e. a sales
+                                                                 channel needs to be on both lists for the item to be
+                                                                 available.
+├ available_from                      datetime                   The first date time at which this variation can be bought
+                                                                 (or ``null``).
+├ available_until                     datetime                   The last date time at which this variation can be bought
+                                                                 (or ``null``).
+├ hide_without_voucher                boolean                    If ``true``, this variation is only shown during the voucher
+                                                                 redemption process, but not in the normal shop
+                                                                 frontend.
 └ position                            integer                    An integer, used for sorting
 addons                                list of objects            Definition of add-ons that can be chosen for this item.
                                                                  Only writable during creation,
@@ -143,6 +159,10 @@ meta_data                             object                     Values set for
    The attributes ``require_membership``, ``require_membership_types``, ``grant_membership_type``, ``grant_membership_duration_like_event``,
     ``grant_membership_duration_days`` and ``grant_membership_duration_months`` have been added.
 
+.. versionchanged:: 4.4
+
+   The attributes ``require_membership_hidden`` attribute has been added.
+
 Notes
 -----
 
@@ -230,6 +250,10 @@ Endpoints
                  "active": true,
                  "require_membership": false,
                  "require_membership_types": [],
+                 "sales_channels": ["web"],
+                 "available_from": null,
+                 "available_until": null,
+                 "hide_without_voucher": false,
                  "description": null,
                  "position": 0
               },
@@ -241,6 +265,10 @@ Endpoints
                  "active": true,
                  "require_membership": false,
                  "require_membership_types": [],
+                 "sales_channels": ["web"],
+                 "available_from": null,
+                 "available_until": null,
+                 "hide_without_voucher": false,
                  "description": null,
                  "position": 1
               }
@@ -337,6 +365,10 @@ Endpoints
              "require_membership": false,
              "require_membership_types": [],
              "description": null,
+             "sales_channels": ["web"],
+             "available_from": null,
+             "available_until": null,
+             "hide_without_voucher": false,
              "position": 0
           },
           {
@@ -347,6 +379,10 @@ Endpoints
              "active": true,
              "require_membership": false,
              "require_membership_types": [],
+             "sales_channels": ["web"],
+             "available_from": null,
+             "available_until": null,
+             "hide_without_voucher": false,
              "description": null,
              "position": 1
           }
@@ -422,6 +458,10 @@ Endpoints
              "active": true,
              "require_membership": false,
              "require_membership_types": [],
+             "sales_channels": ["web"],
+             "available_from": null,
+             "available_until": null,
+             "hide_without_voucher": false,
              "description": null,
              "position": 0
           },
@@ -433,6 +473,10 @@ Endpoints
              "active": true,
              "require_membership": false,
              "require_membership_types": [],
+             "sales_channels": ["web"],
+             "available_from": null,
+             "available_until": null,
+             "hide_without_voucher": false,
              "description": null,
              "position": 1
           }
@@ -497,6 +541,10 @@ Endpoints
              "active": true,
              "require_membership": false,
              "require_membership_types": [],
+             "sales_channels": ["web"],
+             "available_from": null,
+             "available_until": null,
+             "hide_without_voucher": false,
              "description": null,
              "position": 0
           },
@@ -508,6 +556,10 @@ Endpoints
              "active": true,
              "require_membership": false,
              "require_membership_types": [],
+             "sales_channels": ["web"],
+             "available_from": null,
+             "available_until": null,
+             "hide_without_voucher": false,
              "description": null,
              "position": 1
           }
@@ -603,6 +655,10 @@ Endpoints
              "active": true,
              "require_membership": false,
              "require_membership_types": [],
+             "sales_channels": ["web"],
+             "available_from": null,
+             "available_until": null,
+             "hide_without_voucher": false,
              "description": null,
              "position": 0
           },
@@ -614,6 +670,10 @@ Endpoints
              "active": true,
              "require_membership": false,
              "require_membership_types": [],
+             "sales_channels": ["web"],
+             "available_from": null,
+             "available_until": null,
+             "hide_without_voucher": false,
              "description": null,
              "position": 1
           }

doc/api/resources/orders.rst

@@ -128,6 +128,10 @@ last_modified                         datetime                   Last modificati
 
    The ``custom_followup_at`` attribute has been added.
 
+.. versionchanged:: 4.4
+
+   The ``item`` and ``variation`` query parameters have been added.
+
 
 .. _order-position-resource:
 
@@ -415,6 +419,8 @@ List of all orders
    :query string code: Only return orders that match the given order code
    :query string status: Only return orders in the given order status (see above)
    :query string search: Only return orders matching a given search query
+   :query integer item: Only return orders with a position that contains this item ID. *Warning:* Result will also include orders if they contain mixed items, and it will even return orders where the item is only contained in a canceled position.
+   :query integer variation: Only return orders with a position that contains this variation ID. *Warning:* Result will also include orders if they contain mixed items and variations, and it will even return orders where the variation is only contained in a canceled position.
    :query boolean testmode: Only return orders with ``testmode`` set to ``true`` or ``false``
    :query boolean require_approval: If set to ``true`` or ``false``, only categories with this value for the field
                                     ``require_approval`` will be returned.

doc/api/resources/sendmail_rules.rst

@@ -0,0 +1,281 @@
+Automated email rules
+=====================
+
+Resource description
+--------------------
+
+Automated email rules that specify emails that the system will send automatically at a specific point in time, e.g.
+the day of the event.
+
+.. rst-class:: rest-resource-table
+
+===================================== ========================== =======================================================
+Field                                 Type                       Description
+===================================== ========================== =======================================================
+id                                    integer                    Internal ID of the rule
+enabled                               boolean                    If ``false``, the rule is ignored
+subject                               multi-lingual string       The subject of the email
+template                              multi-lingual string       The body of the email
+all_products                          boolean                    If ``true``, the email is sent to buyers of all products
+limit_products                        list of integers           List of product IDs, if ``all_products`` is not set
+include_pending                       boolean                    If ``true``, the email is sent to pending orders. If ``false``,
+                                                                 only paid orders are considered.
+date_is_absolute                      boolean                    If ``true``, the email is set at a specific point in time.
+send_date                             datetime                   If ``date_is_absolute`` is set: Date and time to send the email.
+send_offset_days                      integer                    If ``date_is_absolute`` is not set, this is the number of days
+                                                                 before/after the email is sent.
+send_offset_time                      time                       If ``date_is_absolute`` is not set, this is the time of day the
+                                                                 email is sent on the day specified by ``send_offset_days``.
+offset_to_event_end                   boolean                    If ``true``, ``send_offset_days`` is relative to the event end
+                                                                 date. Otherwise it is relative to the event start date.
+offset_is_after                       boolean                    If ``true``, ``send_offset_days`` is the number of days **after**
+                                                                 the event start or end date. Otherwise it is the number of days
+                                                                 **before**.
+send_to                               string                     Can be ``"orders"`` if the email should be sent to customers
+                                                                 (one email per order),
+                                                                 ``"attendees"`` if the email should be sent to every attendee,
+                                                                 or ``"both"``.
+                                                                 date. Otherwise it is relative to the event start date.
+===================================== ========================== =======================================================
+
+
+Endpoints
+---------
+
+.. http:get:: /api/v1/organizers/(organizer)/events/(event)/sendmail_rules/
+
+   Returns a list of all rules configured for an event.
+
+   **Example request**:
+
+   .. sourcecode:: http
+
+      GET /api/v1/organizers/bigevents/events/sampleconf/sendmail_rules/ HTTP/1.1
+      Host: pretix.eu
+      Accept: application/json, text/javascript
+
+   **Example response**:
+
+   .. sourcecode:: http
+
+      HTTP/1.1 200 OK
+      Vary: Accept
+      Content-Type: application/json
+
+      {
+        "count": 1,
+        "next": null,
+        "previous": null,
+        "results": [
+          {
+            "id": 1,
+            "enabled": true,
+            "subject": {"en": "See you tomorrow!"},
+            "template": {"en": "Don't forget your tickets, download them at {url}"},
+            "all_products": true,
+            "limit_products": [],
+            "include_pending": false,
+            "send_date": null,
+            "send_offset_days": 1,
+            "send_offset_time": "18:00",
+            "date_is_absolute": false,
+            "offset_to_event_end": false,
+            "offset_is_after": false,
+            "send_to": "orders"
+          }
+        ]
+      }
+
+   :query page: The page number in case of a multi-page result set, default is 1
+   :param organizer: The ``slug`` field of a valid organizer
+   :param event: The ``slug`` field of the event to fetch
+   :statuscode 200: no error
+   :statuscode 401: Authentication failure
+   :statuscode 403: The requested organizer does not exist **or** you have no permission to view it.
+
+.. http:get:: /api/v1/organizers/(organizer)/events/(event)/sendmail_rules/(id)/
+
+   Returns information on one rule, identified by its ID.
+
+   **Example request**:
+
+   .. sourcecode:: http
+
+      GET /api/v1/organizers/bigevents/events/sampleconf/sendmail_rules/1/ HTTP/1.1
+      Host: pretix.eu
+      Accept: application/json, text/javascript
+
+   **Example response**:
+
+   .. sourcecode:: http
+
+      HTTP/1.1 200 OK
+      Vary: Accept
+      Content-Type: application/json
+
+      {
+        "id": 1,
+        "enabled": true,
+        "subject": {"en": "See you tomorrow!"},
+        "template": {"en": "Don't forget your tickets, download them at {url}"},
+        "all_products": true,
+        "limit_products": [],
+        "include_pending": false,
+        "send_date": null,
+        "send_offset_days": 1,
+        "send_offset_time": "18:00",
+        "date_is_absolute": false,
+        "offset_to_event_end": false,
+        "offset_is_after": false,
+        "send_to": "orders"
+      }
+
+   :param organizer: The ``slug`` field of the organizer to fetch
+   :param event: The ``slug`` field of the event to fetch
+   :param id: The ``id`` field of the rule to fetch
+   :statuscode 200: no error
+   :statuscode 401: Authentication failure
+   :statuscode 403: The requested organizer/event/rule does not exist **or** you have no permission to view it.
+
+.. http:post:: /api/v1/organizers/(organizer)/events/(event)/sendmail_rules/
+
+   Create a new rule.
+
+   **Example request**:
+
+   .. sourcecode:: http
+
+      POST /api/v1/organizers/bigevents/events/sampleconf/sendmail_rules/ HTTP/1.1
+      Host: pretix.eu
+      Accept: application/json, text/javascript
+      Content-Type: application/json
+      Content-Length: 166
+
+      {
+        "enabled": true,
+        "subject": {"en": "See you tomorrow!"},
+        "template": {"en": "Don't forget your tickets, download them at {url}"},
+        "all_products": true,
+        "limit_products": [],
+        "include_pending": false,
+        "send_date": null,
+        "send_offset_days": 1,
+        "send_offset_time": "18:00",
+        "date_is_absolute": false,
+        "offset_to_event_end": false,
+        "offset_is_after": false,
+        "send_to": "orders"
+      }
+
+   **Example response**:
+
+   .. sourcecode:: http
+
+      HTTP/1.1 201 Created
+      Vary: Accept
+      Content-Type: application/json
+
+      {
+        "id": 1,
+        "enabled": true,
+        "subject": {"en": "See you tomorrow!"},
+        "template": {"en": "Don't forget your tickets, download them at {url}"},
+        "all_products": true,
+        "limit_products": [],
+        "include_pending": false,
+        "send_date": null,
+        "send_offset_days": 1,
+        "send_offset_time": "18:00",
+        "date_is_absolute": false,
+        "offset_to_event_end": false,
+        "offset_is_after": false,
+        "send_to": "orders"
+      }
+
+   :param organizer: The ``slug`` field of the organizer to create a rule for
+   :param event: The ``slug`` field of the event to create a rule for
+   :statuscode 201: no error
+   :statuscode 400: The rule could not be created due to invalid submitted data.
+   :statuscode 401: Authentication failure
+   :statuscode 403: The requested organizer/event does not exist **or** you have no permission to create rules.
+
+
+.. http:patch:: /api/v1/organizers/(organizer)/events/(event)/sendmail_rules/(id)/
+
+   Update a rule. You can also use ``PUT`` instead of ``PATCH``. With ``PUT``, you have to provide all fields of
+   the resource, other fields will be reset to default. With ``PATCH``, you only need to provide the fields that you
+   want to change.
+
+   **Example request**:
+
+   .. sourcecode:: http
+
+      PATCH /api/v1/organizers/bigevents/events/sampleconf/sendmail_rules/1/ HTTP/1.1
+      Host: pretix.eu
+      Accept: application/json, text/javascript
+      Content-Type: application/json
+      Content-Length: 34
+
+      {
+        "enabled": false,
+      }
+
+   **Example response**:
+
+   .. sourcecode:: http
+
+      HTTP/1.1 200 OK
+      Vary: Accept
+      Content-Type: text/javascript
+
+      {
+        "id": 1,
+        "enabled": false,
+        "subject": {"en": "See you tomorrow!"},
+        "template": {"en": "Don't forget your tickets, download them at {url}"},
+        "all_products": true,
+        "limit_products": [],
+        "include_pending": false,
+        "send_date": null,
+        "send_offset_days": 1,
+        "send_offset_time": "18:00",
+        "date_is_absolute": false,
+        "offset_to_event_end": false,
+        "offset_is_after": false,
+        "send_to": "orders"
+      }
+
+   :param organizer: The ``slug`` field of the organizer to modify
+   :param event: The ``slug`` field of the event to modify
+   :param id: The ``id`` field of the rule to modify
+   :statuscode 200: no error
+   :statuscode 400: The rule could not be modified due to invalid submitted data.
+   :statuscode 401: Authentication failure
+   :statuscode 403: The requested organizer/event/rule does not exist **or** you have no permission to change it.
+
+
+.. http:delete:: /api/v1/organizers/(organizer)/events/(event)/sendmail_rules/(id)/
+
+   Delete a rule.
+
+   **Example request**:
+
+   .. sourcecode:: http
+
+      DELETE /api/v1/organizers/bigevents/events/sampleconf/sendmail_rules/1/ HTTP/1.1
+      Host: pretix.eu
+      Accept: application/json, text/javascript
+
+   **Example response**:
+
+   .. sourcecode:: http
+
+      HTTP/1.1 204 No Content
+      Vary: Accept
+
+   :param organizer: The ``slug`` field of the organizer to modify
+   :param event: The ``slug`` field of the event to modify
+   :param id: The ``id`` field of the rule to delete
+   :statuscode 204: no error
+   :statuscode 401: Authentication failure
+   :statuscode 403: The requested organizer/event/rule does not exist **or** you have no permission to change it **or** this rule cannot be deleted since it is currently in use.

doc/development/algorithms/checkin.rst

@@ -0,0 +1,28 @@
+.. spelling: libpretixsync
+
+Check-in algorithms
+===================
+
+When a ticket is scanned at the entrance or exit of an event, we follow a series of steps to determine whether
+the check-in is allowed or not. To understand some of the terms in the following diagrams, you should also check
+out the documentation of the :ref:`ticket redemption API endpoint <rest-checkin-redeem>`.
+
+Server-side
+-----------
+
+The following diagram shows the series of checks executed on the server when a ticket is redeemed through the API.
+Some simplifications have been made, for example the deduplication mechanism based on the ``nonce`` parameter
+to prevent re-uploads of the same scan is not shown.
+
+.. image:: /images/checkin_online.png
+
+Client-side
+-----------
+
+The process of verifying tickets offline is a little different. There are two different approaches,
+depending on whether we have information about all tickets in the local database. The following diagram shows
+the algorithm as currently implemented in recent versions of `libpretixsync`_.
+
+.. image:: /images/checkin_offline.png
+
+.. _libpretixsync: https://github.com/pretix/libpretixsync

doc/development/algorithms/index.rst

@@ -0,0 +1,13 @@
+Algorithms
+==========
+
+The business logic inside pretix is full of complex algorithms making decisions based on all the hundreds of settings
+and input parameters available. Some of them are documented here as graphs, either because fully understanding them is very
+when working on features close to them, or because they also need to be re-implemented by client-side components like our
+ticket scanning apps and we want to ensure the implementations are as similar as possible to avoid confusion.
+
+.. toctree::
+   :maxdepth: 2
+
+   checkin
+   layouts

doc/development/algorithms/layouts.rst

@@ -0,0 +1,15 @@
+.. spelling: pretixPOS
+
+Ticket layout
+=============
+
+When a ticket is exported to PDF, the system needs to decide which of multiple PDF layouts to use. The
+following diagram shows the steps of the decision, showing both the implementation in pretix itself as
+well as the implementation in `pretixPOS`_.
+
+The process can be influenced by plugins, which is demonstrated with the example of the shipping plugin.
+
+.. image:: /images/ticket_layouts.png
+
+
+.. _pretixPOS: https://pretix.eu/about/en/pos

doc/development/contribution/style.rst

@@ -1,6 +1,11 @@
+.. spelling:: Rebase rebasing
+
 Coding style and quality
 ========================
 
+Code
+----
+
 * Basically, we want all python code to follow the `PEP 8`_ standard. There are a few exceptions where
   we see things differently or just aren't that strict. The ``setup.cfg`` file in the project's source
   folder contains definitions that allow `flake8`_ to check for violations automatically. See :ref:`checksandtests`
@@ -20,8 +25,62 @@ Coding style and quality
   test suite are in the style of Python's unit test module. If you extend those files, you might continue in this style,
   but please use ``pytest`` style for any new test files.
 
-* Please keep the first line of your commit messages short. When referencing an issue, please phrase it like
-  ``Fix #123 -- Problems with order creation`` or ``Refs #123 -- Fix this part of that bug``.
+Commits and Pull Requests
+-------------------------
+
+
+
+Most commits should start as pull requests, therefore this applies to the titles of pull requests as well since
+the pull request title will become the commit message on merge. We prefer merging with GitHub's "Squash and merge"
+feature if the PR contains multiple commits that do not carry value to keep. If there is value in keeping the
+individual commits, we use "Rebase and merge" instead. Merge commits should be avoided.
+
+* The commit message should start with a single subject line and can optionally be followed by a commit message body.
+
+  * The subject line should be the shortest possible representation of what the commit changes. Someone who reviewed
+    the commit should able to immediately remember the commit in a couple of weeks based on the subject line and tell
+    it apart from other commits.
+
+  * If there's additional useful information that we should keep, such as reasoning behind the commit, you can
+    add a longer body, separated from the first line by a blank line.
+
+  * The body should explain **what** you changed and more importantly **why** you changed it. There's no need to iterate
+    **how** you changed something.
+
+* The subject line should be capitalized ("Add new feature" instead of "add new feature") and should not end with a period
+  ("Add new feature" instead of "Add new feature.")
+
+* The subject line should be written in imperative mood, as if you were giving a command what the computer should do if the
+  commit is applied. This is how generated commit messages by git itself are already written ("Merge branch …", "Revert …")
+  and makes for short and consistent messages.
+
+  * Good: "Fix typo in template"
+  * Good: "Add Chinese translation"
+  * Good: "Remove deprecated method"
+  * Good: "Bump version to 4.4.0"
+  * Bad: "Fixed bug with …"
+  * Bad: "Fixes bug with …"
+  * Bad: "Fixing bug …"
+
+* If all changes in your commit are in context of a single feature or e.g. a bundled plugin, it makes sense to prefix the
+  subject line with the name of that feature. Examples:
+
+  * "API: Add support for PATCH on customers"
+  * "Docs: Add chapter on alpaca feeding"
+  * "Stripe: Fix duplicate payments"
+  * "Order change form: Fix incorrect validation"
+
+* If your commit references a GitHub issue that is fully resolved by your commit, start your subject line with the issue
+  ID in the form of "Fix #1234 -- Crash in order list". In this case, you can omit the verb "Fix" at the beginning of the
+  second part of the message to avoid repetition of the word "fix". If your commit only partially resolves the issue, use
+  "Refs #1234 -- Crash in order list" instead.
+
+* Applies to pretix employees only: If your commit references a sentry issue, please put it in parentheses at the end
+  of the subject line or inside the body ("Fix crash in order list (PRETIXEU-ABC)"). If your commit references a support
+  ticket, please put it in parentheses at the end of the subject line with a "Z#" prefix ("Fix crash in order list (Z#12345)").
+
+* If your PR was open for a while and might cause conflicts on merge, please prefer rebasing it (``git rebase -i master``)
+  over merging ``master`` into your branch unless it is prohibitively complicated.
 
 
 .. _PEP 8: https://legacy.python.org/dev/peps/pep-0008/

doc/development/implementation/models.rst

@@ -92,6 +92,9 @@ Carts and Orders
 .. autoclass:: pretix.base.models.OrderRefund
    :members:
 
+.. autoclass:: pretix.base.models.Transaction
+   :members:
+
 .. autoclass:: pretix.base.models.CartPosition
    :members:
 

doc/development/index.rst

@@ -8,6 +8,7 @@ Developer documentation
    setup
    contribution/index
    implementation/index
-   translation/index
+   algorithms/index
    api/index
    structure
+   translation/index

doc/development/setup.rst

@@ -26,7 +26,7 @@ Your should install the following on your system:
 * ``libssl`` (Debian package: ``libssl-dev``)
 * ``libxml2`` (Debian package ``libxml2-dev``)
 * ``libxslt`` (Debian package ``libxslt1-dev``)
-* ``libenchant1c2a`` (Debian package ``libenchant1c2a``)
+* ``libenchant-2-2`` (Debian package ``libenchant-2-2``)
 * ``msgfmt`` (Debian package ``gettext``)
 * ``git``
 
@@ -51,7 +51,12 @@ the dependencies might fail::
 
 Working with the code
 ---------------------
-The first thing you need are all the main application's dependencies::
+If you do not have a recent installation of ``nodejs``, install it now::
+
+    curl -sL https://deb.nodesource.com/setup_17.x | sudo -E bash -
+    sudo apt install nodejs
+
+To make sure it is on your path variable, close and reopen your terminal. Now, install the Python-level dependencies of pretix::
 
     cd src/
     pip3 install -e ".[dev]"

doc/images/checkin_offline.puml

@@ -0,0 +1,146 @@
+@startuml
+
+
+partition "data-based check" {
+    "Check based on local database" --> "Is the order in status PAID or PENDING\nand is the position not canceled?"
+    --> if "" then
+        -right->[no] "Return error CANCELED"
+    else
+        -down->[yes] "Is the product part of the check-in list?"
+        --> if "" then
+            -right->[no] "Return error PRODUCT"
+        else
+            -down->[yes] "Is the subevent part of the check-in list?"
+            --> if "" then
+                -right->[no] "Return error INVALID"
+                note bottom: TODO\ninconsistent\nwith online\ncheck
+            else
+                -down->[yes] "Is the order in status PAID?"
+                --> if "" then
+                    -right->[no] "Does the check-in list include pending orders?"
+                    --> if "" then
+                        -right->[no] "Return error UNPAID "
+                    else
+                        -down->[yes] "Is ignore_unpaid set?\n(Has the operator confirmed\nthe checkin?)"
+                        --> if "" then
+                            -right->[no] "Return error UNPAID "
+                        else
+                            -down->[yes] "Is this an entry or exit?"
+                        endif
+                    endif
+                else
+                    -down->[yes] "Is this an entry or exit?"
+                endif
+            endif
+        endif
+    endif
+
+    "Is this an entry or exit?" --> if "" then
+        -right->[entry] Evaluate custom logic (rules)
+        --> if "" then
+            -right->[error] "Return error RULES"
+        else
+            -down->[ok] "Are all required questions answered?"
+            --> if "" then
+                -right->[no] "Return error INCOMPLETE"
+            else
+                -down->[yes] "Does the check-in list allow multi-entry?"
+            endif
+        endif
+    else
+        -->[exit] "Return OK "
+    endif
+
+    "Does the check-in list allow multi-entry?" --> if "" then
+        -right->[yes] "Return OK"
+    else
+        -down->[no] "Is this the first checkin\nfor this ticket on this list?"
+        --> if "" then
+            -right->[yes] "Return OK"
+        else
+            -down->[no] "Are all previous checkins\nfor this ticket on this list exits?"
+            --> if "" then
+                -right->[yes] "Return OK"
+            else
+                -down->[no] "Does the check-in list\n allow entry after exit\nand is the last checkin\nan exit?"
+                --> if "" then
+                    -right->[yes] "Return OK"
+                else
+                    -down->[no] "Return error ALREADY_REDEEMED"
+                endif
+            endif
+        endif
+    endif
+}
+
+partition "dataless check" {
+    "Check based on secret content" --> "Does the secret decode with\nany supported scheme\nand has a valid signature?"
+
+    --> if "" then
+        -down->[yes] "Is the ticket secret on the revocation list?"
+        --> if "" then
+            -right->[yes] "Return error REVOKED"
+        else
+            -down->[no] "Is the product part of the check-in list? "
+            --> if "" then
+                -right->[no] "Return error PRODUCT "
+            else
+                -down->[yes] "Is the subevent part of the check-in list? "
+                --> if "" then
+                    -right->[no] "Return error INVALID  "
+                    note bottom: TODO\ninconsistent\nwith online\ncheck
+                else
+                  --> "Is this an entry or exit? "
+                endif
+            endif
+        endif
+    else
+        -right>[no] "Return error INVALID "
+    endif
+
+    "Is this an entry or exit? " --> if "" then
+        -right->[entry] "Evaluate custom logic (rules) "
+        --> if "" then
+            -right->[error] "Return error RULES "
+        else
+            -down->[ok] "Are all required questions answered? "
+            --> if "" then
+                -right->[no] "Return error INCOMPLETE "
+            else
+                -down->[yes] "Does the check-in list allow multi-entry? "
+            endif
+        endif
+    else
+        -->[exit] " Return OK "
+    endif
+
+    "Does the check-in list allow multi-entry? " --> if "" then
+        -right->[yes] "  Return OK  "
+    else
+        -down->[no] "Are any locally queued checkins for\nthis ticket of this list known?"
+        --> if "" then
+            -right->[no] "  Return OK  "
+        else
+            -down->[yes] "Are all locally queued checkins\nfor this ticket on this list exits? "
+            --> if "" then
+                -right->[yes] "  Return OK  "
+            else
+                -down->[no] "Does the check-in list\n allow entry after exit\nand is the last locally\nqueued checkin\nan exit? "
+                --> if "" then
+                    -right->[yes] "  Return OK  "
+                else
+                    -down->[no] "Return error ALREADY_REDEEMED "
+                endif
+            endif
+        endif
+    endif
+}
+
+(*) --> "Check if order position with\nscanned ticket secret exists"
+--> if "" then
+    -down->[yes] "Check based on local database"
+else
+    -->[no] "Check based on secret content"
+endif
+
+@enduml

doc/images/checkin_online.puml

@@ -0,0 +1,92 @@
+@startuml
+
+(*) --> "Check if order position with\nscanned ticket secret exists"
+--> if "" then
+    -down->[yes] ===CHECK===
+else
+    -->[no] "Check if secret exists\nin revocation list"
+    --> if "" then
+        --> "Is this a forced upload?"
+        --> if "" then
+            -->[yes] ===CHECK===
+        else
+            -right->[no] "Return error REVOKED"
+        endif
+    else
+        -right->[no] "Return error INVALID"
+    endif
+
+endif
+
+
+===CHECK=== -down-> "Is the order in status PAID or PENDING\nand is the position not canceled?"
+--> if "" then
+    -right->[no] "Return error CANCELED"
+else
+    -down->[yes] "Is the product part of the check-in list?"
+    --> if "" then
+        -right->[no] "Return error PRODUCT"
+    else
+        -down->[yes] "Is the subevent part of the check-in list?"
+        --> if "" then
+            -right->[no] "Return error PRODUCT "
+        else
+            -down->[yes] "Is the order in status PAID\nor is this a forced upload?"
+            --> if "" then
+                -right->[no] "Does the check-in list include pending orders?"
+                --> if "" then
+                    -right->[no] "Return error UNPAID "
+                else
+                    -down->[yes] "Is ignore_unpaid set?\n(Has the operator confirmed\nthe checkin?)"
+                    --> if "" then
+                        -right->[no] "Return error UNPAID "
+                    else
+                        -down->[yes] "Is this an entry or exit?\nIs the upload forced?"
+                    endif
+                endif
+            else
+                -down->[yes] "Is this an entry or exit?\nIs the upload forced?"
+            endif
+        endif
+    endif
+endif
+
+"Is this an entry or exit?\nIs the upload forced?" --> if "" then
+    -right->[entry && not force] Evaluate custom logic (rules)
+    --> if "" then
+        -right->[error] "Return error RULES"
+    else
+        -down->[ok] "Are all required questions answered?"
+        --> if "" then
+            -right->[no && questions_supported] "Return error INCOMPLETE"
+        else
+            -down->[yes || not questions_supported] "Does the check-in list allow multi-entry?"
+        endif
+    endif
+else
+    -->[exit || force=true] "Return OK "
+endif
+
+"Does the check-in list allow multi-entry?" --> if "" then
+    -right->[yes] "Return OK"
+else
+    -down->[no] "Is this the first checkin\nfor this ticket on this list?"
+    --> if "" then
+        -right->[yes] "Return OK"
+    else
+        -down->[no] "Are all previous checkins\nfor this ticket on this list exits?"
+        --> if "" then
+            -right->[yes] "Return OK"
+        else
+            -down->[no] "Does the check-in list\n allow entry after exit\nand is the last checkin\nan exit?"
+            --> if "" then
+                -right->[yes] "Return OK"
+            else
+                -down->[no] "Return error ALREADY_REDEEMED"
+            endif
+        endif
+    endif
+endif
+
+
+@enduml

doc/images/ticket_layouts.puml

@@ -0,0 +1,52 @@
+@startuml
+
+(*) --> "Which implementation?"
+--> if "" then
+    -down->[pretixPOS] "Check for TicketLayoutItem with\nsales_channel=pretixpos [libpretixsync]"
+    --> if "" then
+        --> (*)
+    else
+        -->[not found] "Check for TicketLayoutItem with\nsales_channel=web [libpretixsync]"
+        --> if "" then
+            --> (*)
+        else
+            -->[not found] "Use event default [libpretixsync]"
+            --> (*)
+        endif
+    endif
+
+else
+    -right->[pretix] "Check for TicketLayoutItem with\nsales_channel=order.sales_channel"
+    --> if "" then
+        -right-> "Run override_layout plugin signal on result"
+    else
+        -down->[not found] "Check for TicketLayoutItem with\nsales_channel=web"
+        --> if "" then
+            --> "Run override_layout plugin signal on result"
+        else
+            -->[not found] "Use event default"
+            --> "Run override_layout plugin signal on result"
+        endif
+    endif
+endif
+
+
+"Run override_layout plugin signal on result" -> (*)
+
+
+partition pretix_shipping {
+  "Run override_layout plugin signal on result" --> "Check for ShippingLayoutItem with\nmethod=order.shipping_method"
+--> if "" then
+    --> (*)
+else
+    -down->[not found] "Check for ShippingMethod.layout"
+    --> if "" then
+        --> (*)
+    else
+        -down->[not found] "Keep original layout"
+        --> (*)
+    endif
+endif
+}
+
+@enduml

doc/plugins/certificates.rst

@@ -0,0 +1,64 @@
+Certificates of attendance
+==========================
+
+The certificates plugin provides a HTTP API that allows you to download the certificate for a specific attendee.
+
+
+Certificate download
+--------------------
+
+.. http:get:: /api/v1/organizers/(organizer)/events/(event)/orderpositions/(id)/certificate/
+
+   Downloads the certificate for one order position, identified by its internal ID. Download is a two-step
+   process. You will always get a :http:statuscode:`303` response with a ``Location`` header to a different
+   URL. In the background, our server starts preparing the PDF file.
+
+   If you then do a ``GET`` to the URL you were given, you will either receive a :http:statuscode:`409` response
+   indicating to retry after a few seconds, or a :http:statuscode:`200` response with the PDF file.
+
+
+   **Example request**:
+
+   .. sourcecode:: http
+
+      GET /api/v1/organizers/bigevents/events/sampleconf/orderpositions/23442/download/certificate/ HTTP/1.1
+      Host: pretix.eu
+      Accept: application/json, text/javascript
+
+   **Example response**:
+
+   .. sourcecode:: http
+
+      HTTP/1.1 303 See Other
+      Location: /api/v1/organizers/democon/events/3vjrh/orderpositions/426/certificate/?result=1f550651-ae7b-4911-a76c-2be8f348aaa5
+
+   **Example request**:
+
+   .. sourcecode:: http
+
+      GET /api/v1/organizers/bigevents/events/sampleconf/orderpositions/23442/download/certificate/?result=1f550651-ae7b-4911-a76c-2be8f348aaa5 HTTP/1.1
+      Host: pretix.eu
+      Accept: application/json, text/javascript
+
+   **Example response**:
+
+   .. sourcecode:: http
+
+      HTTP/1.1 200 OK
+      Vary: Accept
+      Content-Type: application/pdf
+
+      ...
+
+   :param organizer: The ``slug`` field of the organizer to fetch
+   :param event: The ``slug`` field of the event to fetch
+   :param id: The ``id`` field of the order position to fetch
+   :statuscode 200: File ready for download
+   :statuscode 303: Processing started
+   :statuscode 401: Authentication failure
+   :statuscode 403: The requested organizer/event does not exist **or** you have no permission to view this resource
+                    **or** downloads are not available for this order position at this time. The response content will
+                    contain more details.
+   :statuscode 404: The requested order position or download provider does not exist.
+   :statuscode 409: The file is not yet ready and will now be prepared. Retry the request after waiting for a few
+                    seconds.

doc/plugins/index.rst

@@ -15,5 +15,6 @@ If you want to **create** a plugin, please go to the
    ticketoutputpdf
    badges
    campaigns
+   certificates
    digital
    webinar

doc/spelling_wordlist.txt

@@ -17,6 +17,7 @@ bic
 BIC
 boolean
 booleans
+bugfix
 cancelled
 casted
 Ceph
@@ -77,6 +78,7 @@ mixin
 mixins
 multi
 multidomain
+multiplicator
 namespace
 namespaced
 namespaces

doc/user/events/widget.rst

@@ -4,8 +4,7 @@ Embeddable Widget
 =================
 
 If you want to show your ticket shop on your event website or blog, you can use our JavaScript widget. This way,
-users will not need to leave your site to buy their ticket in most cases. The widget will still open a new tab
-for the checkout if the user is on a mobile device.
+users will not need to leave your site to buy their ticket in most cases.
 
 To obtain the correct HTML code for embedding your event into your website, we recommend that you go to the "Widget"
 tab of your event's settings. You can specify some optional settings there (for example the language of the widget)

src/.update-locales

@@ -34,5 +34,7 @@ git push
 # Unlock Weblate
 for c in $COMPONENTS; do
 	wlc unlock $c;
+done
+for c in $COMPONENTS; do
 	wlc pull $c;
 done

src/pretix/__init__.py

@@ -19,4 +19,4 @@
 # You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
 # <https://www.gnu.org/licenses/>.
 #
-__version__ = "4.1.0"
+__version__ = "4.5.2"

src/pretix/api/auth/devicesecurity.py

@@ -70,9 +70,9 @@ class PretixScanSecurityProfile(AllowListSecurityProfile):
     )
 
 
-class PretixScanNoSyncSecurityProfile(AllowListSecurityProfile):
+class PretixScanNoSyncNoSearchSecurityProfile(AllowListSecurityProfile):
     identifier = 'pretixscan_online_kiosk'
-    verbose_name = _('pretixSCAN (kiosk mode, online only)')
+    verbose_name = _('pretixSCAN (kiosk mode, no order sync, no search)')
     allowlist = (
         ('GET', 'api-v1:version'),
         ('GET', 'api-v1:device.eventselection'),
@@ -99,6 +99,36 @@ class PretixScanNoSyncSecurityProfile(AllowListSecurityProfile):
     )
 
 
+class PretixScanNoSyncSecurityProfile(AllowListSecurityProfile):
+    identifier = 'pretixscan_online_noorders'
+    verbose_name = _('pretixSCAN (online only, no order sync)')
+    allowlist = (
+        ('GET', 'api-v1:version'),
+        ('GET', 'api-v1:device.eventselection'),
+        ('POST', 'api-v1:device.update'),
+        ('POST', 'api-v1:device.revoke'),
+        ('POST', 'api-v1:device.roll'),
+        ('GET', 'api-v1:event-list'),
+        ('GET', 'api-v1:event-detail'),
+        ('GET', 'api-v1:subevent-list'),
+        ('GET', 'api-v1:subevent-detail'),
+        ('GET', 'api-v1:itemcategory-list'),
+        ('GET', 'api-v1:item-list'),
+        ('GET', 'api-v1:question-list'),
+        ('GET', 'api-v1:badgelayout-list'),
+        ('GET', 'api-v1:badgeitem-list'),
+        ('GET', 'api-v1:checkinlist-list'),
+        ('GET', 'api-v1:checkinlist-status'),
+        ('POST', 'api-v1:checkinlist-failed_checkins'),
+        ('GET', 'api-v1:checkinlistpos-list'),
+        ('POST', 'api-v1:checkinlistpos-redeem'),
+        ('GET', 'api-v1:revokedsecrets-list'),
+        ('GET', 'api-v1:orderposition-pdf_image'),
+        ('GET', 'api-v1:event.settings'),
+        ('POST', 'api-v1:upload'),
+    )
+
+
 class PretixPosSecurityProfile(AllowListSecurityProfile):
     identifier = 'pretixpos'
     verbose_name = _('pretixPOS')
@@ -133,6 +163,7 @@ class PretixPosSecurityProfile(AllowListSecurityProfile):
         ('POST', 'api-v1:orderrefund-list'),
         ('POST', 'api-v1:orderrefund-done'),
         ('POST', 'api-v1:cartposition-list'),
+        ('POST', 'api-v1:cartposition-bulk-create'),
         ('GET', 'api-v1:checkinlist-list'),
         ('POST', 'api-v1:checkinlistpos-redeem'),
         ('POST', 'plugins:pretix_posbackend:order.posprintlog'),
@@ -160,6 +191,7 @@ DEVICE_SECURITY_PROFILES = {
         FullAccessSecurityProfile,
         PretixScanSecurityProfile,
         PretixScanNoSyncSecurityProfile,
+        PretixScanNoSyncNoSearchSecurityProfile,
         PretixPosSecurityProfile,
     )
 }

src/pretix/api/migrations/0006_alter_webhook_target_url.py

@@ -0,0 +1,18 @@
+# Generated by Django 3.2.2 on 2021-07-05 07:56
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixapi', '0005_auto_20191028_1541'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='webhook',
+            name='target_url',
+            field=models.URLField(max_length=255),
+        ),
+    ]

src/pretix/api/migrations/0007_alter_webhookcall_target_url.py

@@ -0,0 +1,18 @@
+# Generated by Django 3.2.4 on 2021-09-15 11:06
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixapi', '0006_alter_webhook_target_url'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='webhookcall',
+            name='target_url',
+            field=models.URLField(max_length=255),
+        ),
+    ]

src/pretix/api/models.py

@@ -95,7 +95,7 @@ class OAuthRefreshToken(AbstractRefreshToken):
 class WebHook(models.Model):
     organizer = models.ForeignKey('pretixbase.Organizer', on_delete=models.CASCADE, related_name='webhooks')
     enabled = models.BooleanField(default=True, verbose_name=_("Enable webhook"))
-    target_url = models.URLField(verbose_name=_("Target URL"))
+    target_url = models.URLField(verbose_name=_("Target URL"), max_length=255)
     all_events = models.BooleanField(default=True, verbose_name=_("All events (including newly created ones)"))
     limit_events = models.ManyToManyField('pretixbase.Event', verbose_name=_("Limit to events"), blank=True)
 
@@ -120,7 +120,7 @@ class WebHookEventListener(models.Model):
 class WebHookCall(models.Model):
     webhook = models.ForeignKey('WebHook', on_delete=models.CASCADE, related_name='calls')
     datetime = models.DateTimeField(auto_now_add=True)
-    target_url = models.URLField()
+    target_url = models.URLField(max_length=255)
     action_type = models.CharField(max_length=255)
     is_retry = models.BooleanField(default=False)
     execution_time = models.FloatField(null=True)

src/pretix/api/pagination.py

@@ -0,0 +1,27 @@
+#
+# This file is part of pretix (Community Edition).
+#
+# Copyright (C) 2014-2020 Raphael Michel and contributors
+# Copyright (C) 2020-2021 rami.io GmbH and contributors
+#
+# This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General
+# Public License as published by the Free Software Foundation in version 3 of the License.
+#
+# ADDITIONAL TERMS APPLY: Pursuant to Section 7 of the GNU Affero General Public License, additional terms are
+# applicable granting you additional permissions and placing additional restrictions on your usage of this software.
+# Please refer to the pretix LICENSE file to obtain the full terms applicable to this work. If you did not receive
+# this file, see <https://pretix.eu/about/en/license>.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
+# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
+# <https://www.gnu.org/licenses/>.
+#
+from rest_framework.pagination import PageNumberPagination
+
+
+class Pagination(PageNumberPagination):
+    page_size_query_param = 'page_size'
+    max_page_size = 50

src/pretix/api/serializers/cart.py

@@ -73,53 +73,61 @@ class CartPositionCreateSerializer(I18nAwareModelSerializer):
                 minutes=self.context['event'].settings.get('reservation_time', as_type=int)
             )
 
-        with self.context['event'].lock():
-            new_quotas = (validated_data.get('variation').quotas.filter(subevent=validated_data.get('subevent'))
-                          if validated_data.get('variation')
-                          else validated_data.get('item').quotas.filter(subevent=validated_data.get('subevent')))
-            if len(new_quotas) == 0:
+        new_quotas = (validated_data.get('variation').quotas.filter(subevent=validated_data.get('subevent'))
+                      if validated_data.get('variation')
+                      else validated_data.get('item').quotas.filter(subevent=validated_data.get('subevent')))
+        if len(new_quotas) == 0:
+            raise ValidationError(
+                gettext_lazy('The product "{}" is not assigned to a quota.').format(
+                    str(validated_data.get('item'))
+                )
+            )
+        for quota in new_quotas:
+            avail = quota.availability(_cache=self.context['quota_cache'])
+            if avail[0] != Quota.AVAILABILITY_OK or (avail[1] is not None and avail[1] < 1):
                 raise ValidationError(
-                    gettext_lazy('The product "{}" is not assigned to a quota.').format(
-                        str(validated_data.get('item'))
+                    gettext_lazy('There is not enough quota available on quota "{}" to perform '
+                                 'the operation.').format(
+                        quota.name
                     )
                 )
-            for quota in new_quotas:
-                avail = quota.availability()
-                if avail[0] != Quota.AVAILABILITY_OK or (avail[1] is not None and avail[1] < 1):
-                    raise ValidationError(
-                        gettext_lazy('There is not enough quota available on quota "{}" to perform '
-                                     'the operation.').format(
-                            quota.name
-                        )
-                    )
-            attendee_name = validated_data.pop('attendee_name', '')
-            if attendee_name and not validated_data.get('attendee_name_parts'):
-                validated_data['attendee_name_parts'] = {
-                    '_legacy': attendee_name
-                }
 
-            seated = validated_data.get('item').seat_category_mappings.filter(subevent=validated_data.get('subevent')).exists()
-            if validated_data.get('seat'):
-                if not seated:
-                    raise ValidationError('The specified product does not allow to choose a seat.')
-                try:
-                    seat = self.context['event'].seats.get(seat_guid=validated_data['seat'], subevent=validated_data.get('subevent'))
-                except Seat.DoesNotExist:
-                    raise ValidationError('The specified seat does not exist.')
-                except Seat.MultipleObjectsReturned:
-                    raise ValidationError('The specified seat ID is not unique.')
-                else:
-                    validated_data['seat'] = seat
-                    if not seat.is_available(
-                        sales_channel=validated_data.get('sales_channel', 'web'),
-                        distance_ignore_cart_id=validated_data['cart_id'],
-                    ):
-                        raise ValidationError(gettext_lazy('The selected seat "{seat}" is not available.').format(seat=seat.name))
-            elif seated:
-                raise ValidationError('The specified product requires to choose a seat.')
+        for quota in new_quotas:
+            oldsize = self.context['quota_cache'][quota.pk][1]
+            newsize = oldsize - 1 if oldsize is not None else None
+            self.context['quota_cache'][quota.pk] = (
+                Quota.AVAILABILITY_OK if newsize is None or newsize > 0 else Quota.AVAILABILITY_GONE,
+                newsize
+            )
 
-            validated_data.pop('sales_channel')
-            cp = CartPosition.objects.create(event=self.context['event'], **validated_data)
+        attendee_name = validated_data.pop('attendee_name', '')
+        if attendee_name and not validated_data.get('attendee_name_parts'):
+            validated_data['attendee_name_parts'] = {
+                '_legacy': attendee_name
+            }
+
+        seated = validated_data.get('item').seat_category_mappings.filter(subevent=validated_data.get('subevent')).exists()
+        if validated_data.get('seat'):
+            if not seated:
+                raise ValidationError('The specified product does not allow to choose a seat.')
+            try:
+                seat = self.context['event'].seats.get(seat_guid=validated_data['seat'], subevent=validated_data.get('subevent'))
+            except Seat.DoesNotExist:
+                raise ValidationError('The specified seat does not exist.')
+            except Seat.MultipleObjectsReturned:
+                raise ValidationError('The specified seat ID is not unique.')
+            else:
+                validated_data['seat'] = seat
+                if not seat.is_available(
+                    sales_channel=validated_data.get('sales_channel', 'web'),
+                    distance_ignore_cart_id=validated_data['cart_id'],
+                ):
+                    raise ValidationError(gettext_lazy('The selected seat "{seat}" is not available.').format(seat=seat.name))
+        elif seated:
+            raise ValidationError('The specified product requires to choose a seat.')
+
+        validated_data.pop('sales_channel')
+        cp = CartPosition.objects.create(event=self.context['event'], **validated_data)
 
         for answ_data in answers_data:
             options = answ_data.pop('options')

src/pretix/api/serializers/event.py

@@ -54,7 +54,7 @@ from pretix.base.models.items import SubEventItem, SubEventItemVariation
 from pretix.base.services.seating import (
     SeatProtected, generate_seats, validate_plan_change,
 )
-from pretix.base.settings import validate_event_settings
+from pretix.base.settings import LazyI18nStringList, validate_event_settings
 from pretix.base.signals import api_event_settings_fields
 
 logger = logging.getLogger(__name__)
@@ -704,6 +704,7 @@ class EventSettingsSerializer(SettingsSerializer):
         'payment_term_accept_late',
         'payment_explanation',
         'payment_pending_hidden',
+        'mail_days_order_expire_warning',
         'ticket_download',
         'ticket_download_date',
         'ticket_download_addons',
@@ -733,6 +734,7 @@ class EventSettingsSerializer(SettingsSerializer):
         'invoice_numbers_prefix_cancellations',
         'invoice_numbers_counter_length',
         'invoice_attendee_name',
+        'invoice_event_location',
         'invoice_include_expire_date',
         'invoice_address_explanation_text',
         'invoice_email_attachment',
@@ -762,6 +764,7 @@ class EventSettingsSerializer(SettingsSerializer):
         'cancel_allow_user_paid_refund_as_giftcard',
         'cancel_allow_user_paid_require_approval',
         'change_allow_user_variation',
+        'change_allow_user_addons',
         'change_allow_user_until',
         'change_allow_user_price',
         'primary_color',
@@ -789,6 +792,10 @@ class EventSettingsSerializer(SettingsSerializer):
         data = super().validate(data)
         settings_dict = self.instance.freeze()
         settings_dict.update(data)
+
+        if data.get('confirm_texts') is not None:
+            data['confirm_texts'] = LazyI18nStringList(data['confirm_texts'])
+
         validate_event_settings(self.event, settings_dict)
         return data
 

src/pretix/api/serializers/item.py

@@ -31,9 +31,10 @@
 # Unless required by applicable law or agreed to in writing, software distributed under the Apache License 2.0 is
 # distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations under the License.
-
+import os.path
 from decimal import Decimal
 
+from django.conf import settings
 from django.core.exceptions import ValidationError
 from django.db import transaction
 from django.db.models import QuerySet
@@ -58,7 +59,8 @@ class InlineItemVariationSerializer(I18nAwareModelSerializer):
         model = ItemVariation
         fields = ('id', 'value', 'active', 'description',
                   'position', 'default_price', 'price', 'original_price',
-                  'require_membership', 'require_membership_types',)
+                  'require_membership', 'require_membership_types', 'require_membership_hidden', 'available_from', 'available_until',
+                  'sales_channels', 'hide_without_voucher',)
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
@@ -73,7 +75,8 @@ class ItemVariationSerializer(I18nAwareModelSerializer):
         model = ItemVariation
         fields = ('id', 'value', 'active', 'description',
                   'position', 'default_price', 'price', 'original_price',
-                  'require_membership', 'require_membership_types',)
+                  'require_membership', 'require_membership_types', 'require_membership_hidden', 'available_from', 'available_until',
+                  'sales_channels', 'hide_without_voucher',)
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
@@ -161,7 +164,7 @@ class ItemSerializer(I18nAwareModelSerializer):
     meta_data = MetaDataField(required=False, source='*')
     picture = UploadedFileField(required=False, allow_null=True, allowed_types=(
         'image/png', 'image/jpeg', 'image/gif'
-    ), max_size=10 * 1024 * 1024)
+    ), max_size=settings.FILE_UPLOAD_MAX_SIZE_IMAGE)
 
     class Meta:
         model = Item
@@ -172,7 +175,7 @@ class ItemSerializer(I18nAwareModelSerializer):
                   'min_per_order', 'max_per_order', 'checkin_attention', 'has_variations', 'variations',
                   'addons', 'bundles', 'original_price', 'require_approval', 'generate_tickets',
                   'show_quota_left', 'hidden_if_available', 'allow_waitinglist', 'issue_giftcard', 'meta_data',
-                  'require_membership', 'require_membership_types', 'grant_membership_type',
+                  'require_membership', 'require_membership_types', 'require_membership_hidden', 'grant_membership_type',
                   'grant_membership_duration_like_event', 'grant_membership_duration_days',
                   'grant_membership_duration_months')
         read_only_fields = ('has_variations',)
@@ -245,10 +248,13 @@ class ItemSerializer(I18nAwareModelSerializer):
         addons_data = validated_data.pop('addons') if 'addons' in validated_data else {}
         bundles_data = validated_data.pop('bundles') if 'bundles' in validated_data else {}
         meta_data = validated_data.pop('meta_data', None)
+        picture = validated_data.pop('picture', None)
         item = Item.objects.create(**validated_data)
+        if picture:
+            item.picture.save(os.path.basename(picture.name), picture)
 
         for variation_data in variations_data:
-            require_membership_types = variation_data.pop('require_membership_types')
+            require_membership_types = variation_data.pop('require_membership_types', [])
             v = ItemVariation.objects.create(item=item, **variation_data)
             if require_membership_types:
                 v.require_membership_types.add(*require_membership_types)
@@ -269,7 +275,10 @@ class ItemSerializer(I18nAwareModelSerializer):
 
     def update(self, instance, validated_data):
         meta_data = validated_data.pop('meta_data', None)
+        picture = validated_data.pop('picture', None)
         item = super().update(instance, validated_data)
+        if picture:
+            item.picture.save(os.path.basename(picture.name), picture)
 
         # Meta data
         if meta_data is not None:

src/pretix/api/serializers/order.py

@@ -26,6 +26,7 @@ from collections import Counter, defaultdict
 from decimal import Decimal
 
 import pycountry
+from django.conf import settings
 from django.core.files import File
 from django.db.models import F, Q
 from django.utils.timezone import now
@@ -191,7 +192,7 @@ class AnswerSerializer(I18nAwareModelSerializer):
         )
         if cf.type not in allowed_types:
             raise ValidationError('The submitted file "{fid}" has a file type that is not allowed in this field.'.format(fid=data))
-        if cf.file.size > 10 * 1024 * 1024:
+        if cf.file.size > settings.FILE_UPLOAD_MAX_SIZE_OTHER:
             raise ValidationError('The submitted file "{fid}" is too large to be used in this field.'.format(fid=data))
 
         data['options'] = []
@@ -1403,6 +1404,7 @@ class OrderCreateSerializer(I18nAwareModelSerializer):
                 state=OrderPayment.PAYMENT_STATE_CREATED
             )
 
+        order.create_transactions(is_new=True, fees=fees, positions=pos_map.values())
         return order
 
 
@@ -1426,7 +1428,7 @@ class InlineInvoiceLineSerializer(I18nAwareModelSerializer):
         model = InvoiceLine
         fields = ('position', 'description', 'item', 'variation', 'attendee_name', 'event_date_from',
                   'event_date_to', 'gross_value', 'tax_value', 'tax_rate', 'tax_name', 'fee_type',
-                  'fee_internal_type')
+                  'fee_internal_type', 'event_location')
 
 
 class InvoiceSerializer(I18nAwareModelSerializer):

src/pretix/api/serializers/organizer.py

@@ -275,6 +275,7 @@ class OrganizerSettingsSerializer(SettingsSerializer):
     default_fields = [
         'customer_accounts',
         'customer_accounts_link_by_email',
+        'invoice_regenerate_allowed',
         'contact_mail',
         'imprint_url',
         'organizer_info_text',
@@ -294,6 +295,7 @@ class OrganizerSettingsSerializer(SettingsSerializer):
         'theme_color_background',
         'theme_round_borders',
         'primary_font',
+        'organizer_logo_image_inherit',
         'organizer_logo_image'
     ]
 

src/pretix/api/views/cart.py

@@ -21,14 +21,18 @@
 #
 from django.db import transaction
 from rest_framework import status, viewsets
+from rest_framework.decorators import action
+from rest_framework.exceptions import ValidationError
 from rest_framework.filters import OrderingFilter
 from rest_framework.mixins import CreateModelMixin, DestroyModelMixin
 from rest_framework.response import Response
+from rest_framework.settings import api_settings
 
 from pretix.api.serializers.cart import (
     CartPositionCreateSerializer, CartPositionSerializer,
 )
 from pretix.base.models import CartPosition
+from pretix.base.services.locking import NoLockManager
 
 
 class CartPositionViewSet(CreateModelMixin, DestroyModelMixin, viewsets.ReadOnlyModelViewSet):
@@ -50,18 +54,61 @@ class CartPositionViewSet(CreateModelMixin, DestroyModelMixin, viewsets.ReadOnly
     def get_serializer_context(self):
         ctx = super().get_serializer_context()
         ctx['event'] = self.request.event
+        ctx['quota_cache'] = {}
         return ctx
 
     def create(self, request, *args, **kwargs):
         serializer = CartPositionCreateSerializer(data=request.data, context=self.get_serializer_context())
         serializer.is_valid(raise_exception=True)
-        with transaction.atomic():
+        with transaction.atomic(), self.request.event.lock():
             self.perform_create(serializer)
-            cp = serializer.instance
-            serializer = CartPositionSerializer(cp, context=serializer.context)
-
+        cp = serializer.instance
+        serializer = CartPositionSerializer(cp, context=serializer.context)
         headers = self.get_success_headers(serializer.data)
         return Response(serializer.data, status=status.HTTP_201_CREATED, headers=headers)
 
+    @action(detail=False, methods=['POST'])
+    def bulk_create(self, request, *args, **kwargs):
+        if not isinstance(request.data, list):  # noqa
+            return Response({"error": "Please supply a list"}, status=status.HTTP_400_BAD_REQUEST)
+
+        ctx = self.get_serializer_context()
+        with transaction.atomic():
+            serializers = [
+                CartPositionCreateSerializer(data=d, context=ctx)
+                for d in request.data
+            ]
+
+            lockfn = self.request.event.lock
+            if not any(s.is_valid(raise_exception=False) for s in serializers):
+                lockfn = NoLockManager
+
+            results = []
+            with lockfn():
+                for s in serializers:
+                    if s.is_valid(raise_exception=False):
+                        try:
+                            cp = s.save()
+                        except ValidationError as e:
+                            results.append({
+                                'success': False,
+                                'data': None,
+                                'errors': {api_settings.NON_FIELD_ERRORS_KEY: e.detail},
+                            })
+                        else:
+                            results.append({
+                                'success': True,
+                                'data': CartPositionSerializer(cp, context=ctx).data,
+                                'errors': None,
+                            })
+                    else:
+                        results.append({
+                            'success': False,
+                            'data': None,
+                            'errors': s.errors,
+                        })
+
+        return Response({'results': results}, status=status.HTTP_200_OK)
+
     def perform_create(self, serializer):
         serializer.save()

src/pretix/api/views/checkin.py

@@ -20,6 +20,7 @@
 # <https://www.gnu.org/licenses/>.
 #
 import django_filters
+from django.conf import settings
 from django.core.exceptions import ValidationError
 from django.db import transaction
 from django.db.models import (
@@ -32,6 +33,7 @@ from django.utils.functional import cached_property
 from django.utils.timezone import now
 from django_filters.rest_framework import DjangoFilterBackend, FilterSet
 from django_scopes import scopes_disabled
+from packaging.version import parse
 from rest_framework import viewsets
 from rest_framework.decorators import action
 from rest_framework.fields import DateTimeField
@@ -421,13 +423,20 @@ class CheckinListPositionViewSet(viewsets.ReadOnlyModelViewSet):
             nonce=nonce,
             forced=force,
         )
+        raw_barcode_for_checkin = None
 
         try:
             queryset = self.get_queryset(ignore_status=True, ignore_products=True)
             if self.kwargs['pk'].isnumeric():
                 op = queryset.get(Q(pk=self.kwargs['pk']) | Q(secret=self.kwargs['pk']))
             else:
-                op = queryset.get(secret=self.kwargs['pk'])
+                # In application/x-www-form-urlencoded, you can encodes space ' ' with '+' instead of '%20'.
+                # `id`, however, is part of a path where this technically is not allowed. Old versions of our
+                # scan apps still do it, so we try work around it!
+                try:
+                    op = queryset.get(secret=self.kwargs['pk'])
+                except OrderPosition.DoesNotExist:
+                    op = queryset.get(secret=self.kwargs['pk'].replace('+', ' '))
         except OrderPosition.DoesNotExist:
             revoked_matches = list(self.request.event.revoked_secrets.filter(secret=self.kwargs['pk']))
             if len(revoked_matches) == 0:
@@ -455,7 +464,41 @@ class CheckinListPositionViewSet(viewsets.ReadOnlyModelViewSet):
                     error_reason=Checkin.REASON_INVALID,
                     **common_checkin_args,
                 )
-                raise Http404()
+
+                if force and isinstance(self.request.auth, Device):
+                    # There was a bug in libpretixsync: If you scanned a ticket in offline mode that was
+                    # valid at the time but no longer exists at time of upload, the device would retry to
+                    # upload the same scan over and over again. Since we can't update all devices quickly,
+                    # here's a dirty workaround to make it stop.
+                    try:
+                        brand = self.request.auth.software_brand
+                        ver = parse(self.request.auth.software_version)
+                        legacy_mode = (
+                            (brand == 'pretixSCANPROXY' and ver < parse('0.0.3')) or
+                            (brand == 'pretixSCAN Android' and ver < parse('1.11.2')) or
+                            (brand == 'pretixSCAN' and ver < parse('1.11.2'))
+                        )
+                        if legacy_mode:
+                            return Response({
+                                'status': 'error',
+                                'reason': Checkin.REASON_ALREADY_REDEEMED,
+                                'reason_explanation': None,
+                                'require_attention': False,
+                                '__warning': 'Compatibility hack active due to detected old pretixSCAN version',
+                            }, status=400)
+                    except:  # we don't care e.g. about invalid version numbers
+                        pass
+
+                return Response({
+                    'detail': 'Not found.',  # for backwards compatibility
+                    'status': 'error',
+                    'reason': Checkin.REASON_INVALID,
+                    'reason_explanation': None,
+                    'require_attention': False,
+                }, status=404)
+            elif revoked_matches and force:
+                op = revoked_matches[0].position
+                raw_barcode_for_checkin = self.kwargs['pk']
             else:
                 op = revoked_matches[0].position
                 op.order.log_action('pretix.event.checkin.revoked', data={
@@ -506,7 +549,8 @@ class CheckinListPositionViewSet(viewsets.ReadOnlyModelViewSet):
                     user=self.request.user,
                     auth=self.request.auth,
                     type=type,
-                    raw_barcode=None,
+                    raw_barcode=raw_barcode_for_checkin,
+                    from_revoked_secret=True,
                 )
             except RequiredQuestionsError as e:
                 return Response({
@@ -566,7 +610,7 @@ class CheckinListPositionViewSet(viewsets.ReadOnlyModelViewSet):
         )
         if cf.type not in allowed_types:
             raise ValidationError('The submitted file "{fid}" has a file type that is not allowed in this field.'.format(fid=data))
-        if cf.file.size > 10 * 1024 * 1024:
+        if cf.file.size > settings.FILE_UPLOAD_MAX_SIZE_OTHER:
             raise ValidationError('The submitted file "{fid}" is too large to be used in this field.'.format(fid=data))
 
         return cf.file

src/pretix/api/views/exporters.py

@@ -69,7 +69,7 @@ class ExportersMixin:
         cf = get_object_or_404(CachedFile, id=kwargs['cfid'])
         if cf.file:
             resp = ChunkBasedFileResponse(cf.file.file, content_type=cf.type)
-            resp['Content-Disposition'] = 'attachment; filename="{}"'.format(cf.filename)
+            resp['Content-Disposition'] = 'attachment; filename="{}"'.format(cf.filename).encode("ascii", "ignore")
             return resp
         elif not settings.HAS_CELERY:
             return Response(
@@ -132,7 +132,7 @@ class EventExportersViewSet(ExportersMixin, viewsets.ViewSet):
     def exporters(self):
         exporters = []
         responses = register_data_exporters.send(self.request.event)
-        for ex in sorted([response(self.request.event) for r, response in responses], key=lambda ex: str(ex.verbose_name)):
+        for ex in sorted([response(self.request.event, self.request.organizer) for r, response in responses], key=lambda ex: str(ex.verbose_name)):
             ex._serializer = JobRunSerializer(exporter=ex)
             exporters.append(ex)
         return exporters
@@ -151,7 +151,7 @@ class OrganizerExportersViewSet(ExportersMixin, viewsets.ViewSet):
             organizer=self.request.organizer
         )
         responses = register_multievent_data_exporters.send(self.request.organizer)
-        for ex in sorted([response(events) for r, response in responses if response], key=lambda ex: str(ex.verbose_name)):
+        for ex in sorted([response(events, self.request.organizer) for r, response in responses if response], key=lambda ex: str(ex.verbose_name)):
             ex._serializer = JobRunSerializer(exporter=ex, events=events)
             exporters.append(ex)
         return exporters

src/pretix/api/views/order.py

@@ -92,6 +92,8 @@ with scopes_disabled():
         subevent_after = django_filters.IsoDateTimeFilter(method='subevent_after_qs')
         subevent_before = django_filters.IsoDateTimeFilter(method='subevent_before_qs')
         search = django_filters.CharFilter(method='search_qs')
+        item = django_filters.CharFilter(field_name='all_positions', lookup_expr='item_id')
+        variation = django_filters.CharFilter(field_name='all_positions', lookup_expr='variation_id')
 
         class Meta:
             model = Order
@@ -214,7 +216,9 @@ class OrderViewSet(viewsets.ModelViewSet):
                     'positions',
                     opq.all().prefetch_related(
                         Prefetch('checkins', queryset=Checkin.objects.all()),
-                        'item', 'variation', 'answers', 'answers__options', 'answers__question', 'seat',
+                        'item', 'variation',
+                        Prefetch('answers', queryset=QuestionAnswer.objects.prefetch_related('options', 'question').order_by('question__position')),
+                        'seat',
                     )
                 )
             )
@@ -1451,8 +1455,14 @@ class InvoiceViewSet(viewsets.ReadOnlyModelViewSet):
         inv = self.get_object()
         if inv.canceled:
             raise ValidationError('The invoice has already been canceled.')
+        if not inv.event.settings.invoice_regenerate_allowed:
+            raise PermissionDenied('Invoices may not be changed after they are created.')
         elif inv.shredded:
             raise PermissionDenied('The invoice file is no longer stored on the server.')
+        elif inv.sent_to_organizer:
+            raise PermissionDenied('The invoice file has already been exported.')
+        elif now().astimezone(self.request.event.timezone).date() - inv.date > datetime.timedelta(days=1):
+            raise PermissionDenied('The invoice file is too old to be regenerated.')
         else:
             inv = regenerate_invoice(inv)
             inv.order.log_action(

src/pretix/api/webhooks.py

@@ -261,7 +261,7 @@ def register_default_webhook_events(sender, **kwargs):
         ),
         ParametrizedEventWebhookEvent(
             'pretix.event.deleted',
-            _('Event details changed'),
+            _('Event deleted'),
         ),
         ParametrizedSubEventWebhookEvent(
             'pretix.subevent.added',

src/pretix/base/apps.py

@@ -47,6 +47,7 @@ class PretixBaseConfig(AppConfig):
         from . import notifications  # NOQA
         from . import email  # NOQA
         from .services import auth, checkin, export, mail, tickets, cart, orderimport, orders, invoices, cleanup, update_check, quotas, notifications, vouchers  # NOQA
+        from .models import _transactions  # NOQA
         from django.conf import settings
 
         try:

src/pretix/base/channels.py

@@ -82,6 +82,13 @@ class SalesChannel:
         """
         return False
 
+    @property
+    def customer_accounts_supported(self) -> bool:
+        """
+        If this property is ``True``, checkout will show the customer login step.
+        """
+        return True
+
 
 def get_all_sales_channels():
     global _ALL_CHANNELS

src/pretix/base/email.py

@@ -462,6 +462,16 @@ def base_placeholders(sender, **kwargs):
             lambda waiting_list_entry, event: (waiting_list_entry.subevent or event).get_date_from_display(),
             lambda event: (event if not event.has_subevents or not event.subevents.exists() else event.subevents.first()).get_date_from_display()
         ),
+        SimpleFunctionalMailTextPlaceholder(
+            'url_remove', ['waiting_list_entry', 'event'],
+            lambda waiting_list_entry, event: build_absolute_uri(
+                event, 'presale:event.waitinglist.remove'
+            ) + '?voucher=' + waiting_list_entry.voucher.code,
+            lambda event: build_absolute_uri(
+                event,
+                'presale:event.waitinglist.remove',
+            ) + '?voucher=68CYU2H6ZTP3WLK5',
+        ),
         SimpleFunctionalMailTextPlaceholder(
             'url', ['waiting_list_entry', 'event'],
             lambda waiting_list_entry, event: build_absolute_uri(
@@ -529,6 +539,22 @@ def base_placeholders(sender, **kwargs):
             'voucher_list', ['voucher_list'], lambda voucher_list: '  \n'.join(voucher_list),
             '    68CYU2H6ZTP3WLK5\n    7MB94KKPVEPSMVF2'
         ),
+        SimpleFunctionalMailTextPlaceholder(
+            # join vouchers with two spaces at end of line so markdown-parser inserts a <br>
+            'voucher_url_list', ['event', 'voucher_list'],
+            lambda event, voucher_list: '  \n'.join([
+                build_absolute_uri(
+                    event, 'presale:event.redeem'
+                ) + '?voucher=' + c
+                for c in voucher_list
+            ]),
+            lambda event: '  \n'.join([
+                build_absolute_uri(
+                    event, 'presale:event.redeem'
+                ) + '?voucher=' + c
+                for c in ['68CYU2H6ZTP3WLK5', '7MB94KKPVEPSMVF2']
+            ]),
+        ),
         SimpleFunctionalMailTextPlaceholder(
             'url', ['event', 'voucher_list'], lambda event, voucher_list: build_absolute_uri(event, 'presale:event.index', kwargs={
                 'event': event.slug,

src/pretix/base/exporter.py

@@ -33,7 +33,6 @@
 # License for the specific language governing permissions and limitations under the License.
 
 import io
-import re
 import tempfile
 from collections import OrderedDict, namedtuple
 from decimal import Decimal
@@ -46,23 +45,13 @@ from django.conf import settings
 from django.db.models import QuerySet
 from django.utils.formats import localize
 from django.utils.translation import gettext, gettext_lazy as _
-from openpyxl import Workbook
-from openpyxl.cell.cell import ILLEGAL_CHARACTERS_RE, KNOWN_TYPES
 
 from pretix.base.models import Event
+from pretix.helpers.safe_openpyxl import (  # NOQA: backwards compatibility for plugins using excel_safe
+    SafeWorkbook, remove_invalid_excel_chars as excel_safe,
+)
 
-
-def excel_safe(val):
-    if not isinstance(val, KNOWN_TYPES):
-        val = str(val)
-
-    if isinstance(val, bytes):
-        val = val.decode("utf-8", errors="ignore")
-
-    if isinstance(val, str):
-        val = re.sub(ILLEGAL_CHARACTERS_RE, '', val)
-
-    return val
+__ = excel_safe  # just so the compatbility import above is "used" and doesn't get removed by linter
 
 
 class BaseExporter:
@@ -70,8 +59,9 @@ class BaseExporter:
     This is the base class for all data exporters
     """
 
-    def __init__(self, event, progress_callback=lambda v: None):
+    def __init__(self, event, organizer, progress_callback=lambda v: None):
         self.event = event
+        self.organizer = organizer
         self.progress_callback = progress_callback
         self.is_multievent = isinstance(event, QuerySet)
         if isinstance(event, QuerySet):
@@ -220,9 +210,13 @@ class ListExporter(BaseExporter):
                 writer.writerow(line)
             return self.get_filename() + '.csv', 'text/csv', output.getvalue().encode("utf-8")
 
+    def prepare_xlsx_sheet(self, ws):
+        pass
+
     def _render_xlsx(self, form_data, output_file=None):
-        wb = Workbook(write_only=True)
+        wb = SafeWorkbook(write_only=True)
         ws = wb.create_sheet()
+        self.prepare_xlsx_sheet(ws)
         try:
             ws.title = str(self.verbose_name)
         except:
@@ -234,7 +228,7 @@ class ListExporter(BaseExporter):
                 total = line.total
                 continue
             ws.append([
-                excel_safe(val) for val in line
+                val for val in line
             ])
             if total:
                 counter += 1
@@ -339,7 +333,7 @@ class MultiSheetListExporter(ListExporter):
             return self.get_filename() + '.csv', 'text/csv', output.getvalue().encode("utf-8")
 
     def _render_xlsx(self, form_data, output_file=None):
-        wb = Workbook(write_only=True)
+        wb = SafeWorkbook(write_only=True)
         n_sheets = len(self.sheets)
         for i_sheet, (s, l) in enumerate(self.sheets):
             ws = wb.create_sheet(str(l))
@@ -353,8 +347,7 @@ class MultiSheetListExporter(ListExporter):
                     total = line.total
                     continue
                 ws.append([
-                    excel_safe(val)
-                    for val in line
+                    val for val in line
                 ])
                 if total:
                     counter += 1

src/pretix/base/exporters/invoices.py

@@ -324,7 +324,6 @@ class InvoiceDataExporter(InvoiceExporterMixin, MultiSheetListExporter):
                 _('Tax rate'),
                 _('Tax name'),
                 _('Event start date'),
-
                 _('Date'),
                 _('Order code'),
                 _('E-mail address'),
@@ -348,6 +347,8 @@ class InvoiceDataExporter(InvoiceExporterMixin, MultiSheetListExporter):
                 _('Invoice recipient:') + ' ' + _('Beneficiary'),
                 _('Invoice recipient:') + ' ' + _('Internal reference'),
                 _('Payment providers'),
+                _('Event end date'),
+                _('Location'),
             ]
 
             p_providers = OrderPayment.objects.filter(
@@ -406,7 +407,9 @@ class InvoiceDataExporter(InvoiceExporterMixin, MultiSheetListExporter):
                     ', '.join([
                         str(self.providers.get(p, p)) for p in sorted(set((l.payment_providers or '').split(',')))
                         if p and p != 'free'
-                    ])
+                    ]),
+                    date_format(l.event_date_to, "SHORT_DATE_FORMAT") if l.event_date_to else "",
+                    l.event_location or "",
                 ]
 
     @cached_property

src/pretix/base/exporters/json.py

@@ -55,16 +55,20 @@ class JSONExporter(BaseExporter):
                     'name': str(self.event.organizer.name),
                     'slug': self.event.organizer.slug
                 },
+                'meta_data': self.event.meta_data,
                 'categories': [
                     {
                         'id': category.id,
                         'name': str(category.name),
+                        'description': str(category.description),
+                        'position': category.position,
                         'internal_name': category.internal_name
                     } for category in self.event.categories.all()
                 ],
                 'items': [
                     {
                         'id': item.id,
+                        'position': item.position,
                         'name': str(item.name),
                         'internal_name': str(item.internal_name),
                         'category': item.category_id,
@@ -73,13 +77,35 @@ class JSONExporter(BaseExporter):
                         'tax_name': str(item.tax_rule.name) if item.tax_rule else None,
                         'admission': item.admission,
                         'active': item.active,
+                        'sales_channels': item.sales_channels,
+                        'description': str(item.description),
+                        'available_from': item.available_from,
+                        'available_until': item.available_until,
+                        'require_voucher': item.require_voucher,
+                        'hide_without_voucher': item.hide_without_voucher,
+                        'allow_cancel': item.allow_cancel,
+                        'require_bundling': item.require_bundling,
+                        'min_per_order': item.min_per_order,
+                        'max_per_order': item.max_per_order,
+                        'checkin_attention': item.checkin_attention,
+                        'original_price': item.original_price,
+                        'issue_giftcard': item.issue_giftcard,
+                        'meta_data': item.meta_data,
+                        'require_membership': item.require_membership,
                         'variations': [
                             {
                                 'id': variation.id,
                                 'active': variation.active,
                                 'price': variation.default_price if variation.default_price is not None else
                                 item.default_price,
-                                'name': str(variation)
+                                'name': str(variation),
+                                'description': str(variation.description),
+                                'position': variation.position,
+                                'require_membership': variation.require_membership,
+                                'sales_channels': variation.sales_channels,
+                                'available_from': variation.available_from,
+                                'available_until': variation.available_until,
+                                'hide_without_voucher': variation.hide_without_voucher,
                             } for variation in item.variations.all()
                         ]
                     } for item in self.event.items.select_related('tax_rule').prefetch_related('variations')
@@ -87,7 +113,13 @@ class JSONExporter(BaseExporter):
                 'questions': [
                     {
                         'id': question.id,
+                        'identifier': question.identifier,
+                        'required': question.required,
                         'question': str(question.question),
+                        'position': question.position,
+                        'hidden': question.hidden,
+                        'ask_during_checkin': question.ask_during_checkin,
+                        'help_text': str(question.help_text),
                         'type': question.type
                     } for question in self.event.questions.all()
                 ],
@@ -95,7 +127,18 @@ class JSONExporter(BaseExporter):
                     {
                         'code': order.code,
                         'status': order.status,
+                        'customer': order.customer.identifier if order.customer else None,
+                        'testmode': order.testmode,
                         'user': order.email,
+                        'email': order.email,
+                        'phone': str(order.phone),
+                        'locale': order.locale,
+                        'comment': order.comment,
+                        'custom_followup_at': order.custom_followup_at,
+                        'require_approval': order.require_approval,
+                        'checkin_attention': order.checkin_attention,
+                        'sales_channel': order.sales_channel,
+                        'expires': order.expires,
                         'datetime': order.datetime,
                         'fees': [
                             {
@@ -108,11 +151,21 @@ class JSONExporter(BaseExporter):
                         'positions': [
                             {
                                 'id': position.id,
+                                'positionid': position.positionid,
                                 'item': position.item_id,
                                 'variation': position.variation_id,
+                                'subevent': position.subevent_id,
+                                'seat': position.seat.seat_guid if position.seat else None,
                                 'price': position.price,
+                                'tax_rate': position.tax_rate,
+                                'tax_value': position.tax_value,
                                 'attendee_name': position.attendee_name,
                                 'attendee_email': position.attendee_email,
+                                'company': position.company,
+                                'street': position.street,
+                                'zipcode': position.zipcode,
+                                'country': str(position.country) if position.country else None,
+                                'state': position.state,
                                 'secret': position.secret,
                                 'addon_to': position.addon_to_id,
                                 'answers': [
@@ -124,15 +177,30 @@ class JSONExporter(BaseExporter):
                             } for position in order.positions.all()
                         ]
                     } for order in
-                    self.event.orders.all().prefetch_related('positions', 'positions__answers', 'fees')
+                    self.event.orders.all().prefetch_related('positions', 'positions__answers', 'positions__seat', 'customer', 'fees')
                 ],
                 'quotas': [
                     {
                         'id': quota.id,
                         'size': quota.size,
+                        'subevent': quota.subevent_id,
                         'items': [item.id for item in quota.items.all()],
                         'variations': [variation.id for variation in quota.variations.all()],
                     } for quota in self.event.quotas.all().prefetch_related('items', 'variations')
+                ],
+                'subevents': [
+                    {
+                        'id': se.id,
+                        'name': str(se.name),
+                        'location': str(se.location),
+                        'date_from': se.date_from,
+                        'date_to': se.date_to,
+                        'date_admission': se.date_admission,
+                        'geo_lat': se.geo_lat,
+                        'geo_lon': se.geo_lon,
+                        'is_public': se.is_public,
+                        'meta_data': se.meta_data,
+                    } for se in self.event.subevents.all()
                 ]
             }
         }

src/pretix/base/exporters/orderlist.py

@@ -33,6 +33,7 @@
 # License for the specific language governing permissions and limitations under the License.
 
 from collections import OrderedDict
+from datetime import date, datetime, time
 from decimal import Decimal
 
 import dateutil
@@ -42,10 +43,10 @@ from django.db.models import (
     Case, CharField, Count, DateTimeField, F, IntegerField, Max, Min, OuterRef,
     Q, Subquery, Sum, When,
 )
-from django.db.models.functions import Coalesce, TruncDate
+from django.db.models.functions import Coalesce
 from django.dispatch import receiver
 from django.utils.functional import cached_property
-from django.utils.timezone import get_current_timezone, now
+from django.utils.timezone import get_current_timezone, make_aware, now
 from django.utils.translation import gettext as _, gettext_lazy, pgettext
 
 from pretix.base.models import (
@@ -129,7 +130,7 @@ class OrderListExporter(MultiSheetListExporter):
                  label=_('End event date'),
                  widget=forms.DateInput(attrs={'class': 'datepickerfield'}),
                  required=False,
-                 help_text=_('Only include orders including at least one ticket for a date on or after this date. '
+                 help_text=_('Only include orders including at least one ticket for a date on or before this date. '
                              'Will also include other dates in case of mixed orders!')
              )),
         ]
@@ -181,41 +182,43 @@ class OrderListExporter(MultiSheetListExporter):
 
         if form_data.get('date_from'):
             date_value = form_data.get('date_from')
-            if isinstance(date_value, str):
+            if not isinstance(date_value, date):
                 date_value = dateutil.parser.parse(date_value).date()
+            datetime_value = make_aware(datetime.combine(date_value, time(0, 0, 0)), self.timezone)
 
-            annotations['date'] = TruncDate(f'{rel}datetime')
-            filters['date__gte'] = date_value
+            filters[f'{rel}datetime__gte'] = datetime_value
 
         if form_data.get('date_to'):
             date_value = form_data.get('date_to')
-            if isinstance(date_value, str):
+            if not isinstance(date_value, date):
                 date_value = dateutil.parser.parse(date_value).date()
+            datetime_value = make_aware(datetime.combine(date_value, time(23, 59, 59, 999999)), self.timezone)
 
-            annotations['date'] = TruncDate(f'{rel}datetime')
-            filters['date__lte'] = date_value
+            filters[f'{rel}datetime__lte'] = datetime_value
 
         if form_data.get('event_date_from'):
             date_value = form_data.get('event_date_from')
-            if isinstance(date_value, str):
+            if not isinstance(date_value, date):
                 date_value = dateutil.parser.parse(date_value).date()
+            datetime_value = make_aware(datetime.combine(date_value, time(0, 0, 0)), self.timezone)
 
             annotations['event_date_max'] = Case(
                 When(**{f'{rel}event__has_subevents': True}, then=Max(f'{rel}all_positions__subevent__date_from')),
                 default=F(f'{rel}event__date_from'),
             )
-            filters['event_date_max__gte'] = date_value
+            filters['event_date_max__gte'] = datetime_value
 
         if form_data.get('event_date_to'):
             date_value = form_data.get('event_date_to')
-            if isinstance(date_value, str):
+            if not isinstance(date_value, date):
                 date_value = dateutil.parser.parse(date_value).date()
+            datetime_value = make_aware(datetime.combine(date_value, time(23, 59, 59, 999999)), self.timezone)
 
             annotations['event_date_min'] = Case(
                 When(**{f'{rel}event__has_subevents': True}, then=Min(f'{rel}all_positions__subevent__date_from')),
                 default=F(f'{rel}event__date_from'),
             )
-            filters['event_date_min__lte'] = date_value
+            filters['event_date_min__lte'] = datetime_value
 
         if filters:
             return qs.annotate(**annotations).filter(**filters)
@@ -870,6 +873,78 @@ class QuotaListExporter(ListExporter):
         return '{}_quotas'.format(self.event.slug)
 
 
+def generate_GiftCardTransactionListExporter(organizer):  # hackhack
+    class GiftcardTransactionListExporter(ListExporter):
+        identifier = 'giftcardtransactionlist'
+        verbose_name = gettext_lazy('Gift card transactions')
+
+        @property
+        def additional_form_fields(self):
+            d = [
+                ('date_from',
+                 forms.DateField(
+                     label=_('Start date'),
+                     widget=forms.DateInput(attrs={'class': 'datepickerfield'}),
+                     required=False,
+                 )),
+                ('date_to',
+                 forms.DateField(
+                     label=_('End date'),
+                     widget=forms.DateInput(attrs={'class': 'datepickerfield'}),
+                     required=False,
+                 )),
+            ]
+            d = OrderedDict(d)
+            return d
+
+        def iterate_list(self, form_data):
+            qs = GiftCardTransaction.objects.filter(
+                card__issuer=organizer,
+            ).order_by('datetime').select_related('card', 'order', 'order__event')
+
+            if form_data.get('date_from'):
+                date_value = form_data.get('date_from')
+                if isinstance(date_value, str):
+                    date_value = dateutil.parser.parse(date_value).date()
+                qs = qs.filter(
+                    datetime__gte=make_aware(datetime.combine(date_value, time(0, 0, 0)), self.timezone)
+                )
+
+            if form_data.get('date_to'):
+                date_value = form_data.get('date_to')
+                if isinstance(date_value, str):
+                    date_value = dateutil.parser.parse(date_value).date()
+
+                qs = qs.filter(
+                    datetime__lte=make_aware(datetime.combine(date_value, time(23, 59, 59, 999999)), self.timezone)
+                )
+
+            headers = [
+                _('Gift card code'),
+                _('Test mode'),
+                _('Date'),
+                _('Amount'),
+                _('Currency'),
+                _('Order'),
+            ]
+            yield headers
+
+            for obj in qs:
+                row = [
+                    obj.card.secret,
+                    _('TEST MODE') if obj.card.testmode else '',
+                    obj.datetime.astimezone(self.timezone).strftime('%Y-%m-%d %H:%M:%S'),
+                    obj.value,
+                    obj.card.currency,
+                    obj.order.full_code if obj.order else None,
+                ]
+                yield row
+
+        def get_filename(self):
+            return '{}_giftcardtransactions'.format(organizer.slug)
+    return GiftcardTransactionListExporter
+
+
 class GiftcardRedemptionListExporter(ListExporter):
     identifier = 'giftcardredemptionlist'
     verbose_name = gettext_lazy('Gift card redemptions')
@@ -1062,3 +1137,8 @@ def register_multievent_i_giftcardredemptionlist_exporter(sender, **kwargs):
 @receiver(register_multievent_data_exporters, dispatch_uid="multiexporter_giftcardlist")
 def register_multievent_i_giftcardlist_exporter(sender, **kwargs):
     return generate_GiftCardListExporter(sender)
+
+
+@receiver(register_multievent_data_exporters, dispatch_uid="multiexporter_giftcardtransactionlist")
+def register_multievent_i_giftcardtransactionlist_exporter(sender, **kwargs):
+    return generate_GiftCardTransactionListExporter(sender)

src/pretix/base/forms/questions.py

@@ -37,21 +37,19 @@ import json
 import logging
 from decimal import Decimal
 from io import BytesIO
-from urllib.error import HTTPError
 
 import dateutil.parser
 import pycountry
 import pytz
-import vat_moss.errors
-import vat_moss.id
 from babel import Locale
 from django import forms
+from django.conf import settings
 from django.contrib import messages
 from django.core.exceptions import ValidationError
 from django.core.files.uploadedfile import SimpleUploadedFile
 from django.core.validators import MaxValueValidator, MinValueValidator
 from django.db.models import QuerySet
-from django.forms import Select
+from django.forms import Select, widgets
 from django.utils import translation
 from django.utils.formats import date_format
 from django.utils.html import escape
@@ -75,8 +73,9 @@ from pretix.base.i18n import (
     get_babel_locale, get_language_without_region, language,
 )
 from pretix.base.models import InvoiceAddress, Question, QuestionOption
-from pretix.base.models.tax import (
-    EU_COUNTRIES, cc_to_vat_prefix, is_eu_country,
+from pretix.base.models.tax import VAT_ID_COUNTRIES, ask_for_vat_id
+from pretix.base.services.tax import (
+    VATIDFinalError, VATIDTemporaryError, validate_vat_id,
 )
 from pretix.base.settings import (
     COUNTRIES_WITH_STATE_IN_ADDRESS, PERSON_NAME_SALUTATIONS,
@@ -153,8 +152,9 @@ class NamePartsWidget(forms.MultiWidget):
                     final_attrs,
                     id='%s_%s' % (id_, i),
                     title=self.scheme['fields'][i][1],
-                    placeholder=self.scheme['fields'][i][1],
                 )
+                if not isinstance(widget, widgets.Select):
+                    these_attrs['placeholder'] = self.scheme['fields'][i][1]
                 if self.scheme['fields'][i][0] in REQUIRED_NAME_PARTS:
                     if self.field.required:
                         these_attrs['required'] = 'required'
@@ -507,7 +507,7 @@ class PortraitImageField(SizeValidationMixin, ExtValidationMixin, forms.FileFiel
 
     def __init__(self, *args, **kwargs):
         kwargs.setdefault('ext_whitelist', (".png", ".jpg", ".jpeg", ".jfif", ".tif", ".tiff", ".bmp"))
-        kwargs.setdefault('max_size', 10 * 1024 * 1024)
+        kwargs.setdefault('max_size', settings.FILE_UPLOAD_MAX_SIZE_IMAGE)
         super().__init__(*args, **kwargs)
 
 
@@ -674,7 +674,7 @@ class BaseQuestionsForm(forms.Form):
                     label=label, required=required,
                     min_value=q.valid_number_min or Decimal('0.00'),
                     max_value=q.valid_number_max,
-                    help_text=q.help_text,
+                    help_text=help_text,
                     initial=initial.answer if initial else None,
                 )
             elif q.type == Question.TYPE_STRING:
@@ -739,7 +739,7 @@ class BaseQuestionsForm(forms.Form):
                             ".pptx", ".ppt", ".doc", ".xlsx", ".xls", ".jfif", ".heic", ".heif", ".pages",
                             ".bmp", ".tif", ".tiff"
                         ),
-                        max_size=10 * 1024 * 1024,
+                        max_size=settings.FILE_UPLOAD_MAX_SIZE_OTHER,
                     )
             elif q.type == Question.TYPE_DATE:
                 attrs = {}
@@ -900,7 +900,7 @@ class BaseInvoiceAddressForm(forms.ModelForm):
                 'data-display-dependency': '#id_is_business_1',
                 'autocomplete': 'organization',
             }),
-            'vat_id': forms.TextInput(attrs={'data-display-dependency': '#id_is_business_1', 'data-countries-in-eu': ','.join(EU_COUNTRIES)}),
+            'vat_id': forms.TextInput(attrs={'data-display-dependency': '#id_is_business_1', 'data-countries-with-vat-id': ','.join(VAT_ID_COUNTRIES)}),
             'internal_reference': forms.TextInput,
         }
         labels = {
@@ -920,6 +920,18 @@ class BaseInvoiceAddressForm(forms.ModelForm):
         super().__init__(*args, **kwargs)
         if not event.settings.invoice_address_vatid:
             del self.fields['vat_id']
+        elif self.validate_vat_id:
+            self.fields['vat_id'].help_text = '<br/>'.join([
+                str(_('Optional, but depending on the country you reside in we might need to charge you '
+                      'additional taxes if you do not enter it.')),
+                str(_('If you are registered in Switzerland, you can enter your UID instead.')),
+            ])
+        else:
+            self.fields['vat_id'].help_text = '<br/>'.join([
+                str(_('Optional, but it might be required for you to claim tax benefits on your invoice '
+                      'depending on your and the seller’s country of residence.')),
+                str(_('If you are registered in Switzerland, you can enter your UID instead.')),
+            ])
 
         self.fields['country'].choices = CachedCountries()
 
@@ -951,7 +963,7 @@ class BaseInvoiceAddressForm(forms.ModelForm):
         self.fields['state'].widget.is_required = True
 
         # Without JavaScript the VAT ID field is not hidden, so we empty the field if a country outside the EU is selected.
-        if cc and not is_eu_country(cc) and fprefix + 'vat_id' in self.data:
+        if cc and not ask_for_vat_id(cc) and fprefix + 'vat_id' in self.data:
             self.data = self.data.copy()
             del self.data[fprefix + 'vat_id']
 
@@ -976,7 +988,7 @@ class BaseInvoiceAddressForm(forms.ModelForm):
             scheme=event.settings.name_scheme,
             titles=event.settings.name_scheme_titles,
             label=_('Name'),
-            initial=(self.instance.name_parts if self.instance else self.instance.name_parts),
+            initial=self.instance.name_parts,
         )
         if event.settings.invoice_address_required and not event.settings.invoice_address_company_required and not self.all_optional:
             if not event.settings.invoice_name_required:
@@ -1001,7 +1013,7 @@ class BaseInvoiceAddressForm(forms.ModelForm):
         if not data.get('is_business'):
             data['company'] = ''
             data['vat_id'] = ''
-        if data.get('is_business') and not is_eu_country(data.get('country')):
+        if data.get('is_business') and not ask_for_vat_id(data.get('country')):
             data['vat_id'] = ''
         if self.event.settings.invoice_address_required:
             if data.get('is_business') and not data.get('company'):
@@ -1024,36 +1036,19 @@ class BaseInvoiceAddressForm(forms.ModelForm):
             # Do not save the country if it is the only field set -- we don't know the user even checked it!
             self.cleaned_data['country'] = ''
 
-        if data.get('vat_id') and is_eu_country(data.get('country')) and data.get('vat_id')[:2] != cc_to_vat_prefix(str(data.get('country'))):
-            raise ValidationError(_('Your VAT ID does not match the selected country.'))
-
         if self.validate_vat_id and self.instance.vat_id_validated and 'vat_id' not in self.changed_data:
             pass
-        elif self.validate_vat_id and data.get('is_business') and is_eu_country(data.get('country')) and data.get('vat_id'):
+        elif self.validate_vat_id and data.get('is_business') and ask_for_vat_id(data.get('country')) and data.get('vat_id'):
             try:
-                result = vat_moss.id.validate(data.get('vat_id'))
-                if result:
-                    country_code, normalized_id, company_name = result
-                    self.instance.vat_id_validated = True
-                    self.instance.vat_id = normalized_id
-            except (vat_moss.errors.InvalidError, ValueError):
-                raise ValidationError(_('This VAT ID is not valid. Please re-check your input.'))
-            except vat_moss.errors.WebServiceUnavailableError:
-                logger.exception('VAT ID checking failed for country {}'.format(data.get('country')))
+                normalized_id = validate_vat_id(data.get('vat_id'), str(data.get('country')))
+                self.instance.vat_id_validated = True
+                self.instance.vat_id = normalized_id
+            except VATIDFinalError as e:
+                raise ValidationError(e.message)
+            except VATIDTemporaryError as e:
                 self.instance.vat_id_validated = False
                 if self.request and self.vat_warning:
-                    messages.warning(self.request, _('Your VAT ID could not be checked, as the VAT checking service of '
-                                                     'your country is currently not available. We will therefore '
-                                                     'need to charge VAT on your invoice. You can get the tax amount '
-                                                     'back via the VAT reimbursement process.'))
-            except (vat_moss.errors.WebServiceError, HTTPError):
-                logger.exception('VAT ID checking failed for country {}'.format(data.get('country')))
-                self.instance.vat_id_validated = False
-                if self.request and self.vat_warning:
-                    messages.warning(self.request, _('Your VAT ID could not be checked, as the VAT checking service of '
-                                                     'your country returned an incorrect result. We will therefore '
-                                                     'need to charge VAT on your invoice. Please contact support to '
-                                                     'resolve this manually.'))
+                    messages.warning(self.request, e.message)
         else:
             self.instance.vat_id_validated = False
 

src/pretix/base/forms/user.py

@@ -55,6 +55,7 @@ class UserSettingsForm(forms.ModelForm):
         'pw_current_wrong': _("The current password you entered was not correct."),
         'pw_mismatch': _("Please enter the same password twice"),
         'rate_limit': _("For security reasons, please wait 5 minutes before you try again."),
+        'pw_equal': _("Please choose a password different to your current one.")
     }
 
     old_pw = forms.CharField(max_length=255,
@@ -158,6 +159,12 @@ class UserSettingsForm(forms.ModelForm):
                 code='pw_current'
             )
 
+        if password1 and password1 == old_pw:
+            raise forms.ValidationError(
+                self.error_messages['pw_equal'],
+                code='pw_equal'
+            )
+
         if password1:
             self.instance.set_password(password1)
 

src/pretix/base/forms/widgets.py

@@ -184,7 +184,7 @@ class BusinessBooleanRadio(forms.RadioSelect):
         self.require_business = require_business
         if self.require_business:
             choices = (
-                ('business', _('Business customer')),
+                ('business', _('Business or institutional customer')),
             )
         else:
             choices = (

src/pretix/base/invoice.py

@@ -395,7 +395,13 @@ class ClassicInvoiceRenderer(BaseReportlabInvoiceRenderer):
             return txt
 
         if not self.invoice.event.has_subevents and self.invoice.event.settings.show_dates_on_frontpage:
-            if self.invoice.event.settings.show_date_to and self.invoice.event.date_to:
+            tz = self.invoice.event.timezone
+            show_end_date = (
+                self.invoice.event.settings.show_date_to and
+                self.invoice.event.date_to and
+                self.invoice.event.date_to.astimezone(tz).date() != self.invoice.event.date_from.astimezone(tz).date()
+            )
+            if show_end_date:
                 p_str = (
                     shorten(self.invoice.event.name) + '\n' +
                     pgettext('invoice', '{from_date}\nuntil {to_date}').format(
@@ -550,7 +556,10 @@ class ClassicInvoiceRenderer(BaseReportlabInvoiceRenderer):
         for line in self.invoice.lines.all():
             if has_taxes:
                 tdata.append((
-                    Paragraph(line.description, self.stylesheet['Normal']),
+                    Paragraph(
+                        bleach.clean(line.description, tags=['br']).strip().replace('<br>', '<br/>').replace('\n', '<br />\n'),
+                        self.stylesheet['Normal']
+                    ),
                     "1",
                     localize(line.tax_rate) + " %",
                     money_filter(line.net_value, self.invoice.event.currency),
@@ -558,7 +567,10 @@ class ClassicInvoiceRenderer(BaseReportlabInvoiceRenderer):
                 ))
             else:
                 tdata.append((
-                    Paragraph(line.description, self.stylesheet['Normal']),
+                    Paragraph(
+                        bleach.clean(line.description, tags=['br']).strip().replace('<br>', '<br/>').replace('\n', '<br />\n'),
+                        self.stylesheet['Normal']
+                    ),
                     "1",
                     money_filter(line.gross_value, self.invoice.event.currency),
                 ))
@@ -595,7 +607,7 @@ class ClassicInvoiceRenderer(BaseReportlabInvoiceRenderer):
         table.setStyle(TableStyle(tstyledata))
         story.append(table)
 
-        story.append(Spacer(1, 15 * mm))
+        story.append(Spacer(1, 10 * mm))
 
         if self.invoice.payment_provider_text:
             story.append(Paragraph(
@@ -611,12 +623,14 @@ class ClassicInvoiceRenderer(BaseReportlabInvoiceRenderer):
                 self.invoice.additional_text,
                 self.stylesheet['Normal']
             ))
-            story.append(Spacer(1, 15 * mm))
+            story.append(Spacer(1, 5 * mm))
 
         tstyledata = [
             ('ALIGN', (1, 0), (-1, -1), 'RIGHT'),
             ('LEFTPADDING', (0, 0), (0, -1), 0),
             ('RIGHTPADDING', (-1, 0), (-1, -1), 0),
+            ('TOPPADDING', (0, 0), (-1, -1), 1),
+            ('BOTTOMPADDING', (0, 0), (-1, -1), 1),
             ('FONTSIZE', (0, 0), (-1, -1), 8),
             ('FONTNAME', (0, 0), (-1, -1), self.font_regular),
         ]
@@ -769,44 +783,55 @@ class Modern1Renderer(ClassicInvoiceRenderer):
         ]
 
     def _draw_metadata(self, canvas):
+        # Draws the "invoice number -- date" line. This has gotten a little more complicated since we
+        # encountered some events with very long invoice numbers. In this case, we automatically reduce
+        # the font size until it fits.
         begin_top = 100 * mm
 
-        textobject = canvas.beginText(self.left_margin, self.pagesize[1] - begin_top)
-        textobject.setFont(self.font_regular, 8)
-        textobject.textLine(pgettext('invoice', 'Order code'))
-        textobject.moveCursor(0, 5)
-        textobject.setFont(self.font_regular, 10)
-        textobject.textLine(self.invoice.order.full_code)
-        canvas.drawText(textobject)
-
-        if self.invoice.is_cancellation:
-            textobject = canvas.beginText(self.left_margin + 50 * mm, self.pagesize[1] - begin_top)
+        def _draw(label, value, value_size, x, width):
+            if canvas.stringWidth(value, self.font_regular, value_size) > width and value_size > 6:
+                return False
+            textobject = canvas.beginText(x, self.pagesize[1] - begin_top)
             textobject.setFont(self.font_regular, 8)
-            textobject.textLine(pgettext('invoice', 'Cancellation number'))
+            textobject.textLine(label)
             textobject.moveCursor(0, 5)
-            textobject.setFont(self.font_regular, 10)
-            textobject.textLine(self.invoice.number)
-            canvas.drawText(textobject)
+            textobject.setFont(self.font_regular, value_size)
+            textobject.textLine(value)
+            return textobject
 
-            textobject = canvas.beginText(self.left_margin + 100 * mm, self.pagesize[1] - begin_top)
-            textobject.setFont(self.font_regular, 8)
-            textobject.textLine(pgettext('invoice', 'Original invoice'))
-            textobject.moveCursor(0, 5)
-            textobject.setFont(self.font_regular, 10)
-            textobject.textLine(self.invoice.refers.number)
-            canvas.drawText(textobject)
-        else:
-            textobject = canvas.beginText(self.left_margin + 70 * mm, self.pagesize[1] - begin_top)
-            textobject.textLine(pgettext('invoice', 'Invoice number'))
-            textobject.moveCursor(0, 5)
-            textobject.setFont(self.font_regular, 10)
-            textobject.textLine(self.invoice.number)
-            canvas.drawText(textobject)
+        value_size = 10
+        while value_size >= 5:
+            objects = [
+                _draw(pgettext('invoice', 'Order code'), self.invoice.order.full_code, value_size, self.left_margin, 45 * mm)
+            ]
+
+            p = Paragraph(
+                date_format(self.invoice.date, "DATE_FORMAT"),
+                style=ParagraphStyle(name=f'Normal{value_size}', fontName=self.font_regular, fontSize=value_size, leading=value_size * 1.2)
+            )
+            w = stringWidth(p.text, p.frags[0].fontName, p.frags[0].fontSize)
+            p.wrapOn(canvas, w, 15 * mm)
+            date_x = self.pagesize[0] - w - self.right_margin
+
+            if self.invoice.is_cancellation:
+                objects += [
+                    _draw(pgettext('invoice', 'Cancellation number'), self.invoice.number,
+                          value_size, self.left_margin + 50 * mm, 45 * mm),
+                    _draw(pgettext('invoice', 'Original invoice'), self.invoice.refers.number,
+                          value_size, self.left_margin + 100 * mm, date_x - self.left_margin - 100 * mm - 5 * mm),
+                ]
+            else:
+                objects += [
+                    _draw(pgettext('invoice', 'Invoice number'), self.invoice.number,
+                          value_size, self.left_margin + 70 * mm, date_x - self.left_margin - 70 * mm - 5 * mm),
+                ]
+
+            if all(objects):
+                for o in objects:
+                    canvas.drawText(o)
+                break
+            value_size -= 1
 
-        p = Paragraph(date_format(self.invoice.date, "DATE_FORMAT"), style=self.stylesheet['Normal'])
-        w = stringWidth(p.text, p.frags[0].fontName, p.frags[0].fontSize)
-        p.wrapOn(canvas, w, 15 * mm)
-        date_x = self.pagesize[0] - w - self.right_margin
         p.drawOn(canvas, date_x, self.pagesize[1] - begin_top - 10 - 6)
 
         textobject = canvas.beginText(date_x, self.pagesize[1] - begin_top)

src/pretix/base/management/commands/_migrations.py

@@ -0,0 +1,67 @@
+#
+# This file is part of pretix (Community Edition).
+#
+# Copyright (C) 2014-2020 Raphael Michel and contributors
+# Copyright (C) 2020-2021 rami.io GmbH and contributors
+#
+# This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General
+# Public License as published by the Free Software Foundation in version 3 of the License.
+#
+# ADDITIONAL TERMS APPLY: Pursuant to Section 7 of the GNU Affero General Public License, additional terms are
+# applicable granting you additional permissions and placing additional restrictions on your usage of this software.
+# Please refer to the pretix LICENSE file to obtain the full terms applicable to this work. If you did not receive
+# this file, see <https://pretix.eu/about/en/license>.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
+# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
+# <https://www.gnu.org/licenses/>.
+#
+"""
+Django, for theoretically very valid reasons, creates migrations for *every single thing*
+we change on a model. Even the `help_text`! This makes sense, as we don't know if any
+database backend unknown to us might actually use this information for its database schema.
+
+However, pretix only supports PostgreSQL, MySQL, MariaDB and SQLite and we can be pretty
+certain that some changes to models will never require a change to the database. In this case,
+not creating a migration for certain changes will save us some performance while applying them
+*and* allow for a cleaner git history. Win-win!
+
+Only caveat is that we need to do some dirty monkeypatching to achieve it...
+"""
+from django.db import models
+from django.db.migrations.operations import models as modelops
+from django_countries.fields import CountryField
+
+
+def monkeypatch_migrations():
+    modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("verbose_name")
+    modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("verbose_name_plural")
+    modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("ordering")
+    modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("get_latest_by")
+    modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("default_manager_name")
+    modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("permissions")
+    modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("default_permissions")
+    IGNORED_ATTRS = [
+        # (field type, attribute name, banlist of field sub-types)
+        (models.Field, 'verbose_name', []),
+        (models.Field, 'help_text', []),
+        (models.Field, 'validators', []),
+        (models.Field, 'editable', [models.DateField, models.DateTimeField, models.DateField, models.BinaryField]),
+        (models.Field, 'blank', [models.DateField, models.DateTimeField, models.AutoField, models.NullBooleanField,
+                                 models.TimeField]),
+        (models.CharField, 'choices', [CountryField])
+    ]
+
+    original_deconstruct = models.Field.deconstruct
+
+    def new_deconstruct(self):
+        name, path, args, kwargs = original_deconstruct(self)
+        for ftype, attr, banlist in IGNORED_ATTRS:
+            if isinstance(self, ftype) and not any(isinstance(self, ft) for ft in banlist):
+                kwargs.pop(attr, None)
+        return name, path, args, kwargs
+
+    models.Field.deconstruct = new_deconstruct

src/pretix/base/management/commands/check_order_transactions.py

@@ -0,0 +1,82 @@
+#
+# This file is part of pretix (Community Edition).
+#
+# Copyright (C) 2014-2020 Raphael Michel and contributors
+# Copyright (C) 2020-2021 rami.io GmbH and contributors
+#
+# This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General
+# Public License as published by the Free Software Foundation in version 3 of the License.
+#
+# ADDITIONAL TERMS APPLY: Pursuant to Section 7 of the GNU Affero General Public License, additional terms are
+# applicable granting you additional permissions and placing additional restrictions on your usage of this software.
+# Please refer to the pretix LICENSE file to obtain the full terms applicable to this work. If you did not receive
+# this file, see <https://pretix.eu/about/en/license>.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
+# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
+# <https://www.gnu.org/licenses/>.
+#
+from decimal import Decimal
+
+from django.core.management.base import BaseCommand
+from django.db import models
+from django.db.models import Case, F, OuterRef, Q, Subquery, Sum, Value, When
+from django.db.models.functions import Coalesce
+from django_scopes import scopes_disabled
+
+from pretix.base.models import Order, OrderFee, OrderPosition
+from pretix.base.models.orders import Transaction
+
+
+class Command(BaseCommand):
+    help = "Check order for consistency with their transactions"
+
+    @scopes_disabled()
+    def handle(self, *args, **options):
+        qs = Order.objects.annotate(
+            position_total=Coalesce(
+                Subquery(
+                    OrderPosition.objects.filter(
+                        order=OuterRef('pk')
+                    ).order_by().values('order').annotate(p=Sum('price')).values('p'),
+                    output_field=models.DecimalField(decimal_places=2, max_digits=10)
+                ), Value(0), output_field=models.DecimalField(decimal_places=2, max_digits=10)
+            ),
+            fee_total=Coalesce(
+                Subquery(
+                    OrderFee.objects.filter(
+                        order=OuterRef('pk')
+                    ).order_by().values('order').annotate(p=Sum('value')).values('p'),
+                    output_field=models.DecimalField(decimal_places=2, max_digits=10)
+                ), Value(0), output_field=models.DecimalField(decimal_places=2, max_digits=10)
+            ),
+            tx_total=Coalesce(
+                Subquery(
+                    Transaction.objects.filter(
+                        order=OuterRef('pk')
+                    ).order_by().values('order').annotate(p=Sum(F('price') * F('count'))).values('p'),
+                    output_field=models.DecimalField(decimal_places=2, max_digits=10)
+                ), Value(0), output_field=models.DecimalField(decimal_places=2, max_digits=10)
+            ),
+        ).annotate(
+            correct_total=Case(
+                When(Q(status=Order.STATUS_CANCELED) | Q(status=Order.STATUS_EXPIRED) | Q(require_approval=True),
+                     then=Value(0)),
+                default=F('position_total') + F('fee_total'),
+                output_field=models.DecimalField(decimal_places=2, max_digits=10)
+            ),
+        ).exclude(
+            total=F('position_total') + F('fee_total'),
+            tx_total=F('correct_total')
+        ).select_related('event')
+        for o in qs:
+            if abs(o.tx_total - o.correct_total) < Decimal('0.00001') and abs(o.position_total + o.fee_total - o.total) < Decimal('0.00001'):
+                # Ignore SQLite which treats Decimals like floats…
+                continue
+            print(f"Error in order {o.full_code}: status={o.status}, sum(positions)+sum(fees)={o.position_total + o.fee_total}, "
+                  f"order.total={o.total}, sum(transactions)={o.tx_total}, expected={o.correct_total}")
+
+        self.stderr.write(self.style.SUCCESS(f'Check completed.'))

src/pretix/base/management/commands/create_order_transactions.py

@@ -0,0 +1,95 @@
+#
+# This file is part of pretix (Community Edition).
+#
+# Copyright (C) 2014-2020 Raphael Michel and contributors
+# Copyright (C) 2020-2021 rami.io GmbH and contributors
+#
+# This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General
+# Public License as published by the Free Software Foundation in version 3 of the License.
+#
+# ADDITIONAL TERMS APPLY: Pursuant to Section 7 of the GNU Affero General Public License, additional terms are
+# applicable granting you additional permissions and placing additional restrictions on your usage of this software.
+# Please refer to the pretix LICENSE file to obtain the full terms applicable to this work. If you did not receive
+# this file, see <https://pretix.eu/about/en/license>.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
+# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
+# <https://www.gnu.org/licenses/>.
+#
+import time
+
+from django.core.management.base import BaseCommand
+from django.db.models import F, Max, Q
+from django.utils.timezone import now
+from django_scopes import scopes_disabled
+from tqdm import tqdm
+
+from pretix.base.models import Order
+
+
+class Command(BaseCommand):
+    help = "Create missing order transactions"
+
+    def add_arguments(self, parser):
+        parser.add_argument(
+            "--slowdown",
+            dest="interval",
+            type=int,
+            default=0,
+            help="Interval for staggered execution. If set to a value different then zero, we will "
+                 "wait this many milliseconds between every order we process.",
+        )
+
+    @scopes_disabled()
+    def handle(self, *args, **options):
+        t = 0
+        qs = Order.objects.annotate(
+            last_transaction=Max('transactions__created')
+        ).filter(
+            Q(last_transaction__isnull=True) | Q(last_modified__gt=F('last_transaction')),
+            require_approval=False,
+        ).prefetch_related(
+            'all_positions', 'all_fees'
+        ).order_by(
+            'pk'
+        )
+        last_pk = 0
+        with tqdm(total=qs.count()) as pbar:
+            while True:
+                batch = list(qs.filter(pk__gt=last_pk)[:5000])
+                if not batch:
+                    break
+
+                for o in batch:
+                    if o.last_transaction is None:
+                        tn = o.create_transactions(
+                            positions=o.all_positions.all(),
+                            fees=o.all_fees.all(),
+                            dt_now=o.datetime,
+                            migrated=True,
+                            is_new=True,
+                            _backfill_before_cancellation=True,
+                        )
+                        o.create_transactions(
+                            positions=o.all_positions.all(),
+                            fees=o.all_fees.all(),
+                            dt_now=o.cancellation_date or (o.expires if o.status == Order.STATUS_EXPIRED else o.datetime),
+                            migrated=True,
+                        )
+                    else:
+                        tn = o.create_transactions(
+                            positions=o.all_positions.all(),
+                            fees=o.all_fees.all(),
+                            dt_now=now(),
+                            migrated=True,
+                        )
+                    if tn:
+                        t += 1
+                    time.sleep(0)
+                    pbar.update(1)
+                last_pk = batch[-1].pk
+
+        self.stderr.write(self.style.SUCCESS(f'Created transactions for {t} orders.'))

src/pretix/base/management/commands/export.py

@@ -103,7 +103,7 @@ class Command(BaseCommand):
 
             with language(locale), override(timezone):
                 for receiver, response in signal_result:
-                    ex = response(e, report_status)
+                    ex = response(e, o, report_status)
                     if ex.identifier == options['export_provider']:
                         params = json.loads(options.get('parameters') or '{}')
                         with open(options['output_file'], 'wb') as f:

src/pretix/base/management/commands/makemigrations.py

@@ -32,53 +32,11 @@
 # distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations under the License.
 
-"""
-Django, for theoretically very valid reasons, creates migrations for *every single thing*
-we change on a model. Even the `help_text`! This makes sense, as we don't know if any
-database backend unknown to us might actually use this information for its database schema.
-
-However, pretix only supports PostgreSQL, MySQL, MariaDB and SQLite and we can be pretty
-certain that some changes to models will never require a change to the database. In this case,
-not creating a migration for certain changes will save us some performance while applying them
-*and* allow for a cleaner git history. Win-win!
-
-Only caveat is that we need to do some dirty monkeypatching to achieve it...
-"""
 from django.core.management.commands.makemigrations import Command as Parent
-from django.db import models
-from django.db.migrations.operations import models as modelops
-from django_countries.fields import CountryField
 
-modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("verbose_name")
-modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("verbose_name_plural")
-modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("ordering")
-modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("get_latest_by")
-modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("default_manager_name")
-modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("permissions")
-modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("default_permissions")
-IGNORED_ATTRS = [
-    # (field type, attribute name, banlist of field sub-types)
-    (models.Field, 'verbose_name', []),
-    (models.Field, 'help_text', []),
-    (models.Field, 'validators', []),
-    (models.Field, 'editable', [models.DateField, models.DateTimeField, models.DateField, models.BinaryField]),
-    (models.Field, 'blank', [models.DateField, models.DateTimeField, models.AutoField, models.NullBooleanField,
-                             models.TimeField]),
-    (models.CharField, 'choices', [CountryField])
-]
+from ._migrations import monkeypatch_migrations
 
-original_deconstruct = models.Field.deconstruct
-
-
-def new_deconstruct(self):
-    name, path, args, kwargs = original_deconstruct(self)
-    for ftype, attr, banlist in IGNORED_ATTRS:
-        if isinstance(self, ftype) and not any(isinstance(self, ft) for ft in banlist):
-            kwargs.pop(attr, None)
-    return name, path, args, kwargs
-
-
-models.Field.deconstruct = new_deconstruct
+monkeypatch_migrations()
 
 
 class Command(Parent):

src/pretix/base/management/commands/migrate.py

@@ -32,12 +32,6 @@
 # distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations under the License.
 
-"""
-Django tries to be helpful by suggesting to run "makemigrations" in red font on every "migrate"
-run when there are things we have no migrations for. Usually, this is intended, and running
-"makemigrations" can really screw up the environment of a user, so we want to prevent novice
-users from doing that by going really dirty and filtering it from the output.
-"""
 import sys
 
 from django.core.management.base import OutputWrapper
@@ -45,9 +39,15 @@ from django.core.management.commands.migrate import Command as Parent
 
 
 class OutputFilter(OutputWrapper):
+    """
+    Django tries to be helpful by suggesting to run "makemigrations" in red font on every "migrate"
+    run when there are things we have no migrations for. Usually, this is intended, and running
+    "makemigrations" can really screw up the environment of a user, so we want to prevent novice
+    users from doing that by going really dirty and filtering it from the output.
+    """
     banlist = (
-        "Your models have changes that are not yet reflected",
-        "Run 'manage.py makemigrations' to make new "
+        "have changes that are not yet reflected",
+        "re-run 'manage.py migrate'"
     )
 
     def write(self, msg, style_func=None, ending=None):

src/pretix/base/middleware.py

@@ -208,7 +208,7 @@ def _parse_csp(header):
 
 
 def _render_csp(h):
-    return "; ".join(k + ' ' + ' '.join(v) for k, v in h.items())
+    return "; ".join(k + ' ' + ' '.join(v) for k, v in h.items() if v)
 
 
 def _merge_csp(a, b):

src/pretix/base/migrations/0196_auto_20210523_1322.py

@@ -0,0 +1,38 @@
+# Generated by Django 3.2.2 on 2021-05-23 13:22
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+import pretix.helpers.countries
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0195_auto_20210622_1457'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='invoiceaddress',
+            name='customer',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, related_name='invoice_addresses', to='pretixbase.customer'),
+        ),
+        migrations.CreateModel(
+            name='AttendeeProfile',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False)),
+                ('attendee_name_cached', models.CharField(max_length=255, null=True)),
+                ('attendee_name_parts', models.JSONField(default=dict)),
+                ('attendee_email', models.EmailField(max_length=254, null=True)),
+                ('company', models.CharField(max_length=255, null=True)),
+                ('street', models.TextField(null=True)),
+                ('zipcode', models.CharField(max_length=30, null=True)),
+                ('city', models.CharField(max_length=255, null=True)),
+                ('country', pretix.helpers.countries.FastCountryField(countries=pretix.helpers.countries.CachedCountries, max_length=2, null=True)),
+                ('state', models.CharField(max_length=255, null=True)),
+                ('answers', models.JSONField(default=list)),
+                ('customer', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='attendee_profiles', to='pretixbase.customer')),
+            ],
+        ),
+    ]

src/pretix/base/migrations/0197_auto_20210914_0814.py

@@ -0,0 +1,36 @@
+# Generated by Django 3.2.4 on 2021-09-14 08:14
+
+from django.db import migrations, models
+
+import pretix.base.models.fields
+import pretix.base.models.items
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0196_auto_20210523_1322'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='itemvariation',
+            name='available_from',
+            field=models.DateTimeField(blank=True, null=True),
+        ),
+        migrations.AddField(
+            model_name='itemvariation',
+            name='available_until',
+            field=models.DateTimeField(blank=True, null=True),
+        ),
+        migrations.AddField(
+            model_name='itemvariation',
+            name='hide_without_voucher',
+            field=models.BooleanField(default=False),
+        ),
+        migrations.AddField(
+            model_name='itemvariation',
+            name='sales_channels',
+            field=pretix.base.models.fields.MultiStringField(default=pretix.base.models.items._all_sales_channels_identifiers),
+        ),
+    ]

src/pretix/base/migrations/0198_invoice_sent_to_customer.py

@@ -0,0 +1,21 @@
+# Generated by Django 3.2.4 on 2021-09-30 10:25
+from datetime import datetime
+
+from django.db import migrations, models
+from pytz import UTC
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0197_auto_20210914_0814'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='invoice',
+            name='sent_to_customer',
+            field=models.DateTimeField(blank=True, null=True, default=UTC.localize(datetime(1970, 1, 1, 0, 0, 0, 0))),
+            preserve_default=False,
+        ),
+    ]

src/pretix/base/migrations/0199_auto_20211005_1050.py

@@ -0,0 +1,23 @@
+# Generated by Django 3.2.4 on 2021-10-05 10:50
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0198_invoice_sent_to_customer'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='item',
+            name='require_membership_hidden',
+            field=models.BooleanField(default=False),
+        ),
+        migrations.AddField(
+            model_name='itemvariation',
+            name='require_membership_hidden',
+            field=models.BooleanField(default=False),
+        ),
+    ]

src/pretix/base/migrations/0200_transaction.py

@@ -0,0 +1,38 @@
+# Generated by Django 3.2.4 on 2021-10-18 10:27
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0199_auto_20211005_1050'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Transaction',
+            fields=[
+                ('id', models.BigAutoField(primary_key=True, serialize=False)),
+                ('created', models.DateTimeField(auto_now_add=True, db_index=True)),
+                ('datetime', models.DateTimeField(db_index=True)),
+                ('migrated', models.BooleanField(default=False)),
+                ('positionid', models.PositiveIntegerField(default=1, null=True)),
+                ('count', models.IntegerField(default=1)),
+                ('price', models.DecimalField(decimal_places=2, max_digits=10)),
+                ('tax_rate', models.DecimalField(decimal_places=2, max_digits=7)),
+                ('tax_value', models.DecimalField(decimal_places=2, max_digits=10)),
+                ('fee_type', models.CharField(max_length=100, null=True)),
+                ('internal_type', models.CharField(max_length=255, null=True)),
+                ('item', models.ForeignKey(null=True, on_delete=django.db.models.deletion.PROTECT, to='pretixbase.item')),
+                ('order', models.ForeignKey(on_delete=django.db.models.deletion.PROTECT, related_name='transactions', to='pretixbase.order')),
+                ('subevent', models.ForeignKey(null=True, on_delete=django.db.models.deletion.PROTECT, to='pretixbase.subevent')),
+                ('tax_rule', models.ForeignKey(null=True, on_delete=django.db.models.deletion.PROTECT, to='pretixbase.taxrule')),
+                ('variation', models.ForeignKey(null=True, on_delete=django.db.models.deletion.PROTECT, to='pretixbase.itemvariation')),
+            ],
+            options={
+                'ordering': ('datetime', 'pk'),
+            },
+        ),
+    ]

src/pretix/base/migrations/0201_invoiceline_event_location.py

@@ -0,0 +1,18 @@
+# Generated by Django 3.2.4 on 2021-11-03 09:24
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0200_transaction'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='invoiceline',
+            name='event_location',
+            field=models.TextField(null=True),
+        ),
+    ]

src/pretix/base/migrations/0202_user_needs_password_change.py

@@ -0,0 +1,18 @@
+# Generated by Django 3.2.9 on 2021-11-04 13:05
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0201_invoiceline_event_location'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='user',
+            name='needs_password_change',
+            field=models.BooleanField(default=False),
+        ),
+    ]

src/pretix/base/migrations/0203_orderposition_is_bundled.py

@@ -0,0 +1,17 @@
+# Generated by Django 3.2.2 on 2021-11-08 07:51
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('pretixbase', '0202_user_needs_password_change'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='orderposition',
+            name='is_bundled',
+            field=models.BooleanField(default=False),
+        ),
+    ]

src/pretix/base/migrations/0204_orderposition_backfill_is_bundled.py

@@ -0,0 +1,46 @@
+# Generated by Django 3.2.2 on 2021-11-08 07:51
+
+from django.db import migrations, models
+from django.db.models import Count, OuterRef, Subquery
+from django.db.models.functions import Coalesce
+
+
+def fill_is_bundled(apps, schema_editor):
+    # We cannot really know if a position was bundled or an add-on, but we can at least guess
+    ItemBundle = apps.get_model("pretixbase", "ItemBundle")
+    OrderPosition = apps.get_model("pretixbase", "OrderPosition")
+
+    for ib in ItemBundle.objects.iterator():
+        OrderPosition.all.alias(
+            pos_earlier=Coalesce(Subquery(
+                OrderPosition.all.filter(
+                    canceled=False,
+                    addon_to=OuterRef('addon_to'),
+                    item=ib.bundled_item,
+                    variation=ib.bundled_variation,
+                    positionid__lt=OuterRef('positionid'),
+                ).values('addon_to').order_by().annotate(c=Count('*')).values('c'),
+                output_field=models.IntegerField()
+            ), 0)
+        ).filter(
+            canceled=False,
+            addon_to__item=ib.base_item,
+            item=ib.bundled_item,
+            variation=ib.bundled_variation,
+            pos_earlier__lt=ib.count,
+        ).update(
+            is_bundled=True
+        )
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('pretixbase', '0203_orderposition_is_bundled'),
+    ]
+
+    operations = [
+        migrations.RunPython(
+            fill_is_bundled,
+            migrations.RunPython.noop,
+        ),
+    ]

src/pretix/base/models/__init__.py

@@ -42,8 +42,9 @@ from .notifications import NotificationSetting
 from .orders import (
     AbstractPosition, CachedCombinedTicket, CachedTicket, CartPosition,
     InvoiceAddress, Order, OrderFee, OrderPayment, OrderPosition, OrderRefund,
-    QuestionAnswer, RevokedTicketSecret, cachedcombinedticket_name,
-    cachedticket_name, generate_position_secret, generate_secret,
+    QuestionAnswer, RevokedTicketSecret, Transaction,
+    cachedcombinedticket_name, cachedticket_name, generate_position_secret,
+    generate_secret,
 )
 from .organizer import (
     Organizer, Organizer_SettingsStore, Team, TeamAPIToken, TeamInvite,

src/pretix/base/models/_transactions.py

@@ -0,0 +1,113 @@
+#
+# This file is part of pretix (Community Edition).
+#
+# Copyright (C) 2014-2020 Raphael Michel and contributors
+# Copyright (C) 2020-2021 rami.io GmbH and contributors
+#
+# This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General
+# Public License as published by the Free Software Foundation in version 3 of the License.
+#
+# ADDITIONAL TERMS APPLY: Pursuant to Section 7 of the GNU Affero General Public License, additional terms are
+# applicable granting you additional permissions and placing additional restrictions on your usage of this software.
+# Please refer to the pretix LICENSE file to obtain the full terms applicable to this work. If you did not receive
+# this file, see <https://pretix.eu/about/en/license>.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
+# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
+# <https://www.gnu.org/licenses/>.
+#
+
+"""
+This module contains helper functions that are supposed to call out code paths missing calls to
+``Order.create_transaction()`` by actively breaking them. Read the docstring of the ``Transaction`` class for a
+detailed reasoning why this exists.
+"""
+import inspect
+import logging
+import os
+import threading
+
+from django.conf import settings
+from django.db import transaction
+
+dirty_transactions = threading.local()
+
+logger = logging.getLogger(__name__)
+fail_loudly = os.getenv('PRETIX_DIRTY_TRANSACTIONS_QUIET', 'false' if settings.DEBUG else 'true') not in ('true', 'True', 'on', '1')
+
+
+class DirtyTransactionsForOrderException(Exception):
+    pass
+
+
+def _fail(message):
+    if fail_loudly:
+        raise DirtyTransactionsForOrderException(message)
+    else:
+        if settings.SENTRY_ENABLED:
+            import sentry_sdk
+
+            sentry_sdk.capture_message(message, "fatal")
+
+        logger.warning(message, stack_info=True)
+
+
+def _check_for_dirty_orders():
+    if getattr(dirty_transactions, 'order_ids', None) is None:
+        dirty_transactions.order_ids = set()
+    try:
+        if dirty_transactions.order_ids and dirty_transactions.order_ids != {None}:
+            _fail(
+                f"In the transaction that just ended, you created or modified an Order, OrderPosition, or OrderFee "
+                f"object in a way that you should have called `order.create_transactions()` afterwards. The transaction "
+                f"still went through and your data can be fixed with the `create_order_transactions` management command "
+                f"but you should update your code to prevent this from happening. Affected order IDs: {dirty_transactions.order_ids}"
+            )
+    finally:
+        dirty_transactions.order_ids.clear()
+
+
+def _transactions_mark_order_dirty(order_id, using=None):
+    if "PYTEST_CURRENT_TEST" in os.environ:
+        # We don't care about Order.objects.create() calls in test code so let's try to figure out if this is test code
+        # or not.
+        for frame in inspect.stack():
+            if 'pretix/base/models/orders' in frame.filename:
+                continue
+            elif 'test_' in frame.filename or 'conftest.py in frame.filename':
+                return
+            elif 'pretix/' in frame.filename or 'pretix_' in frame.filename:
+                # This went through non-test code, let's consider it non-test
+                break
+
+    if order_id is None:
+        return
+
+    conn = transaction.get_connection(using)
+    if not conn.in_atomic_block:
+        _fail(
+            "You modified an Order, OrderPosition, or OrderFee object in a way that should create "
+            "a new Transaction object within the same database transaction, however you are not "
+            "doing it inside a database transaction!"
+        )
+
+    if getattr(dirty_transactions, 'order_ids', None) is None:
+        dirty_transactions.order_ids = set()
+
+    if _check_for_dirty_orders not in [func for savepoint_id, func in conn.run_on_commit]:
+        transaction.on_commit(_check_for_dirty_orders, using)
+        dirty_transactions.order_ids.clear()  # This is necessary to clean up after old threads with rollbacked transactions
+
+    dirty_transactions.order_ids.add(order_id)
+
+
+def _transactions_mark_order_clean(order_id):
+    if getattr(dirty_transactions, 'order_ids', None) is None:
+        dirty_transactions.order_ids = set()
+    try:
+        dirty_transactions.order_ids.remove(order_id)
+    except KeyError:
+        pass

src/pretix/base/models/auth.py

@@ -113,6 +113,8 @@ class User(AbstractBaseUser, PermissionsMixin, LoggingMixin):
     :type date_joined: datetime
     :param locale: The user's preferred locale code.
     :type locale: str
+    :param needs_password_change: Whether this user's password needs to be changed.
+    :type needs_password_change: bool
     :param timezone: The user's preferred timezone.
     :type timezone: str
     """
@@ -130,6 +132,8 @@ class User(AbstractBaseUser, PermissionsMixin, LoggingMixin):
                                    verbose_name=_('Is site admin'))
     date_joined = models.DateTimeField(auto_now_add=True,
                                        verbose_name=_('Date joined'))
+    needs_password_change = models.BooleanField(default=False,
+                                                verbose_name=_('Force user to select a new password'))
     locale = models.CharField(max_length=50,
                               choices=settings.LANGUAGES,
                               default=settings.LANGUAGE_CODE,

src/pretix/base/models/customers.py

@@ -19,19 +19,22 @@
 # You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
 # <https://www.gnu.org/licenses/>.
 #
+import pycountry
 from django.conf import settings
 from django.contrib.auth.hashers import (
     check_password, is_password_usable, make_password,
 )
 from django.db import models
+from django.db.models import F, Q
 from django.utils.crypto import get_random_string, salted_hmac
-from django.utils.translation import gettext_lazy as _
+from django.utils.translation import gettext_lazy as _, pgettext_lazy
 from django_scopes import ScopedManager, scopes_disabled
 
 from pretix.base.banlist import banned
 from pretix.base.models.base import LoggedModel
 from pretix.base.models.organizer import Organizer
 from pretix.base.settings import PERSON_NAME_SCHEMES
+from pretix.helpers.countries import FastCountryField
 
 
 class Customer(LoggedModel):
@@ -88,6 +91,8 @@ class Customer(LoggedModel):
         self.all_logentries().update(data={}, shredded=True)
         self.orders.all().update(customer=None)
         self.memberships.all().update(attendee_name_parts=None)
+        self.attendee_profiles.all().delete()
+        self.invoice_addresses.all().delete()
 
     @scopes_disabled()
     def assign_identifier(self):
@@ -174,3 +179,94 @@ class Customer(LoggedModel):
                 continue
             ctx['name_%s' % f] = self.name_parts.get(f, '')
         return ctx
+
+    @property
+    def stored_addresses(self):
+        return self.invoice_addresses(manager='profiles')
+
+    def usable_memberships(self, for_event, testmode=False):
+        return self.memberships.active(for_event).with_usages().filter(
+            Q(membership_type__max_usages__isnull=True) | Q(usages__lt=F('membership_type__max_usages')),
+            testmode=testmode,
+        )
+
+
+class AttendeeProfile(models.Model):
+    customer = models.ForeignKey(
+        Customer,
+        related_name='attendee_profiles',
+        on_delete=models.CASCADE
+    )
+    attendee_name_cached = models.CharField(
+        max_length=255,
+        verbose_name=_("Attendee name"),
+        blank=True, null=True,
+    )
+    attendee_name_parts = models.JSONField(
+        blank=True, default=dict
+    )
+    attendee_email = models.EmailField(
+        verbose_name=_("Attendee email"),
+        blank=True, null=True,
+    )
+    company = models.CharField(max_length=255, blank=True, verbose_name=_('Company name'), null=True)
+    street = models.TextField(verbose_name=_('Address'), blank=True, null=True)
+    zipcode = models.CharField(max_length=30, verbose_name=_('ZIP code'), blank=True, null=True)
+    city = models.CharField(max_length=255, verbose_name=_('City'), blank=True, null=True)
+    country = FastCountryField(verbose_name=_('Country'), blank=True, blank_label=_('Select country'), null=True)
+    state = models.CharField(max_length=255, verbose_name=pgettext_lazy('address', 'State'), blank=True, null=True)
+    answers = models.JSONField(default=list)
+
+    objects = ScopedManager(organizer='customer__organizer')
+
+    @property
+    def attendee_name(self):
+        if not self.attendee_name_parts:
+            return None
+        if '_legacy' in self.attendee_name_parts:
+            return self.attendee_name_parts['_legacy']
+        if '_scheme' in self.attendee_name_parts:
+            scheme = PERSON_NAME_SCHEMES[self.attendee_name_parts['_scheme']]
+        else:
+            scheme = PERSON_NAME_SCHEMES[self.customer.organizer.settings.name_scheme]
+        return scheme['concatenation'](self.attendee_name_parts).strip()
+
+    @property
+    def state_name(self):
+        sd = pycountry.subdivisions.get(code='{}-{}'.format(self.country, self.state))
+        if sd:
+            return sd.name
+        return self.state
+
+    @property
+    def state_for_address(self):
+        from pretix.base.settings import COUNTRIES_WITH_STATE_IN_ADDRESS
+        if not self.state or str(self.country) not in COUNTRIES_WITH_STATE_IN_ADDRESS:
+            return ""
+        if COUNTRIES_WITH_STATE_IN_ADDRESS[str(self.country)][1] == 'long':
+            return self.state_name
+        return self.state
+
+    def describe(self):
+        from .items import Question
+        from .orders import QuestionAnswer
+
+        parts = [
+            self.attendee_name,
+            self.attendee_email,
+            self.company,
+            self.street,
+            (self.zipcode or '') + ' ' + (self.city or '') + ' ' + (self.state_for_address or ''),
+            self.country.name,
+        ]
+        for a in self.answers:
+            value = a.get('value')
+            try:
+                value = ", ".join(value.values())
+            except AttributeError:
+                value = str(value)
+            answer = QuestionAnswer(question=Question(type=a.get('question_type')), answer=value)
+            val = str(answer)
+            parts.append(f'{a["field_label"]}: {val}')
+
+        return '\n'.join([str(p).strip() for p in parts if p and str(p).strip()])

src/pretix/base/models/event.py

@@ -20,6 +20,7 @@
 # <https://www.gnu.org/licenses/>.
 #
 
+import logging
 # This file is based on an earlier version of pretix which was released under the Apache License 2.0. The full text of
 # the Apache License 2.0 can be obtained at <http://www.apache.org/licenses/LICENSE-2.0>.
 #
@@ -56,6 +57,7 @@ from django.urls import reverse
 from django.utils.crypto import get_random_string
 from django.utils.formats import date_format
 from django.utils.functional import cached_property
+from django.utils.html import format_html
 from django.utils.timezone import make_aware, now
 from django.utils.translation import gettext, gettext_lazy as _
 from django_scopes import ScopedManager, scopes_disabled
@@ -73,6 +75,8 @@ from pretix.helpers.thumb import get_thumbnail
 from ..settings import settings_hierarkey
 from .organizer import Organizer, Team
 
+logger = logging.getLogger(__name__)
+
 
 class EventMixin:
     def clean(self):
@@ -142,7 +146,7 @@ class EventMixin:
             ("SHORT_" if short else "") + ("DATETIME_FORMAT" if self.settings.show_times and show_times else "DATE_FORMAT")
         )
 
-    def get_date_range_display(self, tz=None, force_show_end=False) -> str:
+    def get_date_range_display(self, tz=None, force_show_end=False, as_html=False) -> str:
         """
         Returns a formatted string containing the start date and the end date
         of the event with respect to the current locale and to the ``show_date_to``
@@ -150,8 +154,40 @@ class EventMixin:
         """
         tz = tz or self.timezone
         if (not self.settings.show_date_to and not force_show_end) or not self.date_to:
+            if as_html:
+                return format_html(
+                    "<time datetime=\"{}\">{}</time>",
+                    _date(self.date_from.astimezone(tz), "Y-m-d"),
+                    _date(self.date_from.astimezone(tz), "DATE_FORMAT"),
+                )
             return _date(self.date_from.astimezone(tz), "DATE_FORMAT")
-        return daterange(self.date_from.astimezone(tz), self.date_to.astimezone(tz))
+        return daterange(self.date_from.astimezone(tz), self.date_to.astimezone(tz), as_html)
+
+    def get_date_range_display_as_html(self, tz=None, force_show_end=False) -> str:
+        return self.get_date_range_display(tz, force_show_end, as_html=True)
+
+    def get_time_range_display(self, tz=None, force_show_end=False) -> str:
+        """
+        Returns a formatted string containing the start time and sometimes the end time
+        of the event with respect to the current locale and to the ``show_date_to``
+        setting. Dates are not shown. This is usually used in combination with get_date_range_display
+        """
+        tz = tz or self.timezone
+
+        show_date_to = self.date_to and (self.settings.show_date_to or force_show_end) and (
+            # Show date to if start and end are on the same day ("08:00-10:00")
+            self.date_to.astimezone(tz).date() == self.date_from.astimezone(tz).date() or
+            # Show date to if start and end are on consecutive days and less than 24h ("23:00-03:00")
+            (self.date_to.astimezone(tz).date() == self.date_from.astimezone(tz).date() + timedelta(days=1) and
+             self.date_to.astimezone(tz).time() < self.date_from.astimezone(tz).time())
+            # Do not show end time if this is a 5-day event because there's no way to make it understandable
+        )
+        if show_date_to:
+            return '{} – {}'.format(
+                _date(self.date_from.astimezone(tz), "TIME_FORMAT"),
+                _date(self.date_to.astimezone(tz), "TIME_FORMAT"),
+            )
+        return _date(self.date_from.astimezone(tz), "TIME_FORMAT")
 
     @property
     def timezone(self):
@@ -242,6 +278,10 @@ class EventMixin:
         ).values('items')
         sq_active_variation = ItemVariation.objects.filter(
             Q(active=True)
+            & Q(sales_channels__contains=channel)
+            & Q(hide_without_voucher=False)
+            & Q(Q(available_from__isnull=True) | Q(available_from__lte=now()))
+            & Q(Q(available_until__isnull=True) | Q(available_until__gte=now()))
             & Q(item__active=True)
             & Q(Q(item__available_from__isnull=True) | Q(item__available_from__lte=now()))
             & Q(Q(item__available_until__isnull=True) | Q(item__available_until__gte=now()))
@@ -492,7 +532,7 @@ class Event(EventMixin, LoggedModel):
         default=False
     )
     seating_plan = models.ForeignKey('SeatingPlan', on_delete=models.PROTECT, null=True, blank=True,
-                                     related_name='events')
+                                     related_name='events', verbose_name=_('Seating plan'))
 
     last_modified = models.DateTimeField(
         auto_now=True, db_index=True
@@ -525,6 +565,8 @@ class Event(EventMixin, LoggedModel):
         self.settings.ticketoutput_pdf__enabled = True
         self.settings.ticketoutput_passbook__enabled = True
         self.settings.event_list_type = 'calendar'
+        self.settings.invoice_email_attachment = True
+        self.settings.name_scheme = 'given_family'
 
     @property
     def social_image(self):
@@ -534,9 +576,17 @@ class Event(EventMixin, LoggedModel):
         logo_file = self.settings.get('logo_image', as_type=str, default='')[7:]
         og_file = self.settings.get('og_image', as_type=str, default='')[7:]
         if og_file:
-            img = get_thumbnail(og_file, '1200').thumb.url
+            try:
+                img = get_thumbnail(og_file, '1200').thumb.url
+            except:
+                logger.exception(f'Failed to create thumbnail of {og_file}')
+                img = default_storage.url(og_file)
         elif logo_file:
-            img = get_thumbnail(logo_file, '5000x120').thumb.url
+            try:
+                img = get_thumbnail(logo_file, '5000x1200').thumb.url
+            except:
+                logger.exception(f'Failed to create thumbnail of {logo_file}')
+                img = default_storage.url(logo_file)
         if img:
             return urljoin(build_absolute_uri(self, 'presale:event.index'), img)
 
@@ -741,7 +791,9 @@ class Event(EventMixin, LoggedModel):
                 ia.bundled_variation = variation_map[ia.bundled_variation.pk]
             ia.save()
 
+        quota_map = {}
         for q in Quota.objects.filter(event=other, subevent__isnull=True).prefetch_related('items', 'variations'):
+            quota_map[q.pk] = q
             items = list(q.items.all())
             vars = list(q.variations.all())
             oldid = q.pk
@@ -865,7 +917,7 @@ class Event(EventMixin, LoggedModel):
         event_copy_data.send(
             sender=self, other=other,
             tax_map=tax_map, category_map=category_map, item_map=item_map, variation_map=variation_map,
-            question_map=question_map, checkin_list_map=checkin_list_map
+            question_map=question_map, checkin_list_map=checkin_list_map, quota_map=quota_map,
         )
 
         if has_custom_style:
@@ -1004,6 +1056,11 @@ class Event(EventMixin, LoggedModel):
                 | Q(date_to__gte=now() - timedelta(hours=24))
             )
         )  # order_by doesn't make sense with I18nField
+        if ordering in ("date_ascending", "date_descending"):
+            # if primary order is by date, then order in database
+            # this allows to limit/slice results
+            return subevs.order_by(*orderfields)
+
         for f in reversed(orderfields):
             if f.startswith('-'):
                 subevs = sorted(subevs, key=attrgetter(f[1:]), reverse=True)
@@ -1113,15 +1170,18 @@ class Event(EventMixin, LoggedModel):
         self.items.all().delete()
         self.subevents.all().delete()
 
-    def set_active_plugins(self, modules, allow_restricted=False):
+    def get_available_plugins(self):
         from pretix.base.plugins import get_all_plugins
 
-        plugins_active = self.get_plugins()
-        plugins_available = {
+        return {
             p.module: p for p in get_all_plugins(self)
             if not p.name.startswith('.') and getattr(p, 'visible', True)
         }
 
+    def set_active_plugins(self, modules, allow_restricted=False):
+        plugins_active = self.get_plugins()
+        plugins_available = self.get_available_plugins()
+
         enable = [m for m in modules if m not in plugins_active and m in plugins_available]
 
         for module in enable:
@@ -1150,6 +1210,10 @@ class Event(EventMixin, LoggedModel):
             plugins_active.remove(module)
             self.set_active_plugins(plugins_active)
 
+            plugins_available = self.get_available_plugins()
+            if hasattr(plugins_available[module].app, 'uninstalled'):
+                getattr(plugins_available[module].app, 'uninstalled')(self)
+
         regenerate_css.apply_async(args=(self.pk,))
 
     @staticmethod
@@ -1259,7 +1323,7 @@ class SubEvent(EventMixin, LoggedModel):
         verbose_name=_("Frontpage text")
     )
     seating_plan = models.ForeignKey('SeatingPlan', on_delete=models.PROTECT, null=True, blank=True,
-                                     related_name='subevents')
+                                     related_name='subevents', verbose_name=_('Seating plan'))
 
     items = models.ManyToManyField('Item', through='SubEventItem')
     variations = models.ManyToManyField('ItemVariation', through='SubEventItemVariation')
@@ -1369,7 +1433,7 @@ class SubEvent(EventMixin, LoggedModel):
         return self.event.currency
 
     def allow_delete(self):
-        return not self.orderposition_set.exists()
+        return not self.orderposition_set.exists() and not self.transaction_set.exists()
 
     def delete(self, *args, **kwargs):
         clear_cache = kwargs.pop('clear_cache', False)

src/pretix/base/models/invoices.py

@@ -159,6 +159,8 @@ class Invoice(models.Model):
     # False: The invoice wasn't sent and never will, because sending was not configured at the time of the check.
     sent_to_organizer = models.BooleanField(null=True, blank=True)
 
+    sent_to_customer = models.DateTimeField(null=True, blank=True)
+
     file = models.FileField(null=True, blank=True, upload_to=invoice_filename, max_length=255)
 
     objects = ScopedManager(organizer='event__organizer')
@@ -235,7 +237,7 @@ class Invoice(models.Model):
     def _get_invoice_number_from_order(self):
         return '{order}-{count}'.format(
             order=self.order.code,
-            count=Invoice.objects.filter(event=self.event, order=self.order).count() + 1,
+            count=Invoice.objects.filter(event=self.event, prefix=self.prefix, invoice_no__startswith=f"{self.order.code}-", order=self.order).count() + 1,
         )
 
     def save(self, *args, **kwargs):
@@ -262,6 +264,7 @@ class Invoice(models.Model):
                     self.invoice_no = self._get_invoice_number_from_order()
                 try:
                     with transaction.atomic():
+                        self.full_invoice_no = self.prefix + self.invoice_no
                         return super().save(*args, **kwargs)
                 except DatabaseError:
                     # Suppress duplicate key errors and try again
@@ -300,6 +303,9 @@ class Invoice(models.Model):
     def __repr__(self):
         return '<Invoice {} / {}>'.format(self.full_invoice_no, self.pk)
 
+    def __str__(self):
+        return self.full_invoice_no
+
 
 class InvoiceLine(models.Model):
     """
@@ -323,6 +329,8 @@ class InvoiceLine(models.Model):
     :type event_date_from: datetime
     :param event_date_to: Event end date of the (sub)event at the time the invoice was created
     :type event_date_to: datetime
+    :param event_location: Event location of the (sub)event at the time the invoice was created
+    :type event_location: str
     :param item: The item this line refers to
     :type item: Item
     :param variation: The variation this line refers to
@@ -340,6 +348,7 @@ class InvoiceLine(models.Model):
     subevent = models.ForeignKey('SubEvent', null=True, blank=True, on_delete=models.PROTECT)
     event_date_from = models.DateTimeField(null=True)
     event_date_to = models.DateTimeField(null=True)
+    event_location = models.TextField(null=True, blank=True)
     item = models.ForeignKey('Item', null=True, blank=True, on_delete=models.PROTECT)
     variation = models.ForeignKey('ItemVariation', null=True, blank=True, on_delete=models.PROTECT)
     attendee_name = models.TextField(null=True, blank=True)

src/pretix/base/models/items.py

@@ -523,6 +523,12 @@ class Item(LoggedModel):
         verbose_name=_('Allowed membership types'),
         blank=True,
     )
+    require_membership_hidden = models.BooleanField(
+        verbose_name=_('Hide without a valid membership'),
+        help_text=_('Do not show this unless the customer is logged in and has a valid membership. Be aware that '
+                    'this means it will never be visible in the widget.'),
+        default=False,
+    )
     grant_membership_type = models.ForeignKey(
         'MembershipType',
         null=True, blank=True,
@@ -687,9 +693,9 @@ class Item(LoggedModel):
         return res
 
     def allow_delete(self):
-        from pretix.base.models.orders import OrderPosition
+        from pretix.base.models.orders import OrderPosition, Transaction
 
-        return not OrderPosition.all.filter(item=self).exists()
+        return not Transaction.objects.filter(item=self).exists() and not OrderPosition.all.filter(item=self).exists()
 
     @property
     def includes_mixed_tax_rate(self):
@@ -736,6 +742,11 @@ class Item(LoggedModel):
         return OrderedDict((k, v) for k, v in sorted(data.items(), key=lambda k: k[0]))
 
 
+def _all_sales_channels_identifiers():
+    from pretix.base.channels import get_all_sales_channels
+    return list(get_all_sales_channels().keys())
+
+
 class ItemVariation(models.Model):
     """
     A variation of a product. For example, if your item is 'T-Shirt'
@@ -761,7 +772,7 @@ class ItemVariation(models.Model):
     )
     value = I18nCharField(
         max_length=255,
-        verbose_name=_('Description')
+        verbose_name=_('Variation')
     )
     active = models.BooleanField(
         default=True,
@@ -797,6 +808,35 @@ class ItemVariation(models.Model):
         verbose_name=_('Membership types'),
         blank=True,
     )
+    require_membership_hidden = models.BooleanField(
+        verbose_name=_('Hide without a valid membership'),
+        help_text=_('Do not show this unless the customer is logged in and has a valid membership. Be aware that '
+                    'this means it will never be visible in the widget.'),
+        default=False,
+    )
+    available_from = models.DateTimeField(
+        verbose_name=_("Available from"),
+        null=True, blank=True,
+        help_text=_('This variation will not be sold before the given date.')
+    )
+    available_until = models.DateTimeField(
+        verbose_name=_("Available until"),
+        null=True, blank=True,
+        help_text=_('This variation will not be sold after the given date.')
+    )
+    sales_channels = fields.MultiStringField(
+        verbose_name=_('Sales channels'),
+        default=_all_sales_channels_identifiers,
+        help_text=_('The sales channel selection for the product as a whole takes precedence, so if a sales channel is '
+                    'selected here but not on product level, the variation will not be available.'),
+        blank=True,
+    )
+    hide_without_voucher = models.BooleanField(
+        verbose_name=_('This variation will only be shown if a voucher matching the product is redeemed.'),
+        default=False,
+        help_text=_('This variation will be hidden from the event page until the user enters a voucher '
+                    'that unlocks this variation.')
+    )
 
     objects = ScopedManager(organizer='item__event__organizer')
 
@@ -918,16 +958,37 @@ class ItemVariation(models.Model):
         return self.position < other.position
 
     def allow_delete(self):
-        from pretix.base.models.orders import CartPosition, OrderPosition
+        from pretix.base.models.orders import (
+            CartPosition, OrderPosition, Transaction,
+        )
 
         return (
-            not OrderPosition.objects.filter(variation=self).exists()
+            not Transaction.objects.filter(variation=self).exists()
+            and not OrderPosition.objects.filter(variation=self).exists()
             and not CartPosition.objects.filter(variation=self).exists()
         )
 
     def is_only_variation(self):
         return ItemVariation.objects.filter(item=self.item).count() == 1
 
+    def is_available_by_time(self, now_dt: datetime=None) -> bool:
+        now_dt = now_dt or now()
+        if self.available_from and self.available_from > now_dt:
+            return False
+        if self.available_until and self.available_until < now_dt:
+            return False
+        return True
+
+    def is_available(self, now_dt: datetime=None) -> bool:
+        """
+        Returns whether this item is available according to its ``active`` flag
+        and its ``available_from`` and ``available_until`` fields
+        """
+        now_dt = now_dt or now()
+        if not self.active or not self.is_available_by_time(now_dt):
+            return False
+        return True
+
 
 class ItemAddOn(models.Model):
     """
@@ -1051,7 +1112,7 @@ class ItemBundle(models.Model):
     )
     count = models.PositiveIntegerField(
         default=1,
-        verbose_name=_('Number')
+        verbose_name=_('Quantity')
     )
     designated_price = models.DecimalField(
         default=Decimal('0.00'), blank=True,
@@ -1620,6 +1681,8 @@ class Quota(LoggedModel):
 
     @staticmethod
     def clean_items(event, items, variations):
+        if not items:
+            return
         for item in items:
             if event != item.event:
                 raise ValidationError(_('One or more items do not belong to this event.'))

src/pretix/base/models/memberships.py

@@ -95,6 +95,7 @@ class MembershipQuerySet(models.QuerySet):
 
     def active(self, ev):
         return self.filter(
+            canceled=False,
             date_start__lte=ev.date_from,
             date_end__gte=ev.date_from
         )
@@ -175,7 +176,7 @@ class Membership(models.Model):
         else:
             dt = now()
 
-        return dt >= self.date_start and dt <= self.date_end
+        return not self.canceled and dt >= self.date_start and dt <= self.date_end
 
     def allow_delete(self):
         return self.testmode and not self.orderposition_set.exists()

src/pretix/base/models/orders.py

@@ -75,11 +75,14 @@ from pretix.base.email import get_email_context
 from pretix.base.i18n import language
 from pretix.base.models import Customer, User
 from pretix.base.reldate import RelativeDateWrapper
-from pretix.base.services.locking import NoLockManager
+from pretix.base.services.locking import LOCK_TIMEOUT, NoLockManager
 from pretix.base.settings import PERSON_NAME_SCHEMES
 from pretix.base.signals import order_gracefully_delete
 
 from ...helpers.countries import CachedCountries, FastCountryField
+from ._transactions import (
+    _fail, _transactions_mark_order_clean, _transactions_mark_order_dirty,
+)
 from .base import LockModel, LoggedModel
 from .event import Event, SubEvent
 from .items import Item, ItemVariation, Question, QuestionOption, Quota
@@ -262,6 +265,11 @@ class Order(LockModel, LoggedModel):
     def __str__(self):
         return self.full_code
 
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        if 'require_approval' not in self.get_deferred_fields() and 'status' not in self.get_deferred_fields():
+            self.__initial_status_paid_or_pending = self.status in (Order.STATUS_PENDING, Order.STATUS_PAID) and not self.require_approval
+
     def gracefully_delete(self, user=None, auth=None):
         from . import GiftCard, GiftCardTransaction, Membership, Voucher
 
@@ -289,6 +297,7 @@ class Order(LockModel, LoggedModel):
         OrderPosition.all.filter(order=self, addon_to__isnull=False).delete()
         OrderPosition.all.filter(order=self).delete()
         OrderFee.all.filter(order=self).delete()
+        Transaction.objects.filter(order=self).delete()
         self.refunds.all().delete()
         self.payments.all().delete()
         self.event.cache.delete('complain_testmode_orders')
@@ -419,6 +428,8 @@ class Order(LockModel, LoggedModel):
                 is_underpaid=Case(
                     When(Q(status=Order.STATUS_PAID) & Q(pending_sum_t__gt=1e-8),
                          then=Value(1)),
+                    When(Q(status=Order.STATUS_CANCELED) & Q(pending_sum_rc__gt=1e-8),
+                         then=Value(1)),
                     default=Value(0),
                     output_field=models.IntegerField()
                 )
@@ -442,7 +453,27 @@ class Order(LockModel, LoggedModel):
             self.datetime = now()
         if not self.expires:
             self.set_expires()
-        super().save(**kwargs)
+
+        is_new = not self.pk
+        update_fields = kwargs.get('update_fields', [])
+        if 'require_approval' not in self.get_deferred_fields() and 'status' not in self.get_deferred_fields():
+            status_paid_or_pending = self.status in (Order.STATUS_PENDING, Order.STATUS_PAID) and not self.require_approval
+            if status_paid_or_pending != self.__initial_status_paid_or_pending:
+                _transactions_mark_order_dirty(self.pk, using=kwargs.get('using', None))
+        elif (
+            not kwargs.get('force_save_with_deferred_fields', None) and
+            (not update_fields or ('require_approval' not in update_fields and 'status' not in update_fields))
+        ):
+            _fail("It is unsafe to call save() on an OrderFee with deferred fields since we can't check if you missed "
+                  "creating a transaction. Call save(force_save_with_deferred_fields=True) if you really want to do "
+                  "this.")
+
+        r = super().save(**kwargs)
+
+        if is_new:
+            _transactions_mark_order_dirty(self.pk, using=kwargs.get('using', None))
+
+        return r
 
     def touch(self):
         self.save(update_fields=['last_modified'])
@@ -541,7 +572,7 @@ class Order(LockModel, LoggedModel):
             fee += self.event.settings.cancel_allow_user_paid_keep_percentage / Decimal('100.0') * (self.total - fee)
         if self.event.settings.cancel_allow_user_paid_keep:
             fee += self.event.settings.cancel_allow_user_paid_keep
-        return round_decimal(fee, self.event.currency)
+        return round_decimal(min(fee, self.total), self.event.currency)
 
     @property
     @scopes_disabled()
@@ -550,6 +581,7 @@ class Order(LockModel, LoggedModel):
         Returns whether or not this order can be canceled by the user.
         """
         from .checkin import Checkin
+        from .items import ItemAddOn
 
         if self.status not in (Order.STATUS_PENDING, Order.STATUS_PAID) or not self.count_positions:
             return False
@@ -575,7 +607,10 @@ class Order(LockModel, LoggedModel):
         if self.user_change_deadline and now() > self.user_change_deadline:
             return False
 
-        return self.event.settings.change_allow_user_variation and any([op.has_variations for op in positions])
+        return (
+            (self.event.settings.change_allow_user_variation and any([op.has_variations for op in positions])) or
+            (self.event.settings.change_allow_user_addons and ItemAddOn.objects.filter(base_item_id__in=[op.item_id for op in positions]).exists())
+        )
 
     @property
     @scopes_disabled()
@@ -783,6 +818,7 @@ class Order(LockModel, LoggedModel):
     def ticket_download_available(self):
         return self.event.settings.ticket_download and (
             self.event.settings.ticket_download_date is None
+            or self.ticket_download_date is None
             or now() > self.ticket_download_date
         ) and (
             self.status == Order.STATUS_PAID
@@ -996,6 +1032,59 @@ class Order(LockModel, LoggedModel):
                 continue
             yield op
 
+    def create_transactions(self, is_new=False, positions=None, fees=None, dt_now=None, migrated=False,
+                            _backfill_before_cancellation=False, save=True):
+        dt_now = dt_now or now()
+
+        # Count the transactions we already have
+        current_transaction_count = Counter()
+        if not is_new:
+            for t in Transaction.objects.filter(order=self):  # do not use related manager, we want to avoid cached data
+                current_transaction_count[Transaction.key(t)] += t.count
+
+        # Count the transactions we'd actually need
+        target_transaction_count = Counter()
+        if (_backfill_before_cancellation or self.status in (Order.STATUS_PENDING, Order.STATUS_PAID)) and not self.require_approval:
+            positions = self.positions.all() if positions is None else positions
+            for p in positions:
+                if p.canceled and not _backfill_before_cancellation:
+                    continue
+                target_transaction_count[Transaction.key(p)] += 1
+
+            fees = self.fees.all() if fees is None else fees
+            for f in fees:
+                if f.canceled and not _backfill_before_cancellation:
+                    continue
+                target_transaction_count[Transaction.key(f)] += 1
+
+        keys = set(target_transaction_count.keys()) | set(current_transaction_count.keys())
+        create = []
+        for k in keys:
+            positionid, itemid, variationid, subeventid, price, taxrate, taxruleid, taxvalue, feetype, internaltype = k
+            d = target_transaction_count[k] - current_transaction_count[k]
+            if d:
+                create.append(Transaction(
+                    order=self,
+                    datetime=dt_now,
+                    migrated=migrated,
+                    positionid=positionid,
+                    count=d,
+                    item_id=itemid,
+                    variation_id=variationid,
+                    subevent_id=subeventid,
+                    price=price,
+                    tax_rate=taxrate,
+                    tax_rule_id=taxruleid,
+                    tax_value=taxvalue,
+                    fee_type=feetype,
+                    internal_type=internaltype,
+                ))
+        create.sort(key=lambda t: (0 if t.count < 0 else 1, t.positionid or 0))
+        if save:
+            Transaction.objects.bulk_create(create)
+        _transactions_mark_order_clean(self.pk)
+        return create
+
 
 def answerfile_name(instance, filename: str) -> str:
     secret = get_random_string(length=32, allowed_chars=string.ascii_letters + string.digits)
@@ -1221,6 +1310,7 @@ class AbstractPosition(models.Model):
     seat = models.ForeignKey(
         'Seat', null=True, blank=True, on_delete=models.PROTECT
     )
+    is_bundled = models.BooleanField(default=False)
 
     company = models.CharField(max_length=255, blank=True, verbose_name=_('Company name'), null=True)
     street = models.TextField(verbose_name=_('Address'), blank=True, null=True)
@@ -1457,7 +1547,7 @@ class OrderPayment(models.Model):
         return self.order.event.get_payment_providers(cached=True).get(self.provider)
 
     @transaction.atomic()
-    def _mark_paid(self, force, count_waitinglist, user, auth, ignore_date=False, overpaid=False):
+    def _mark_paid_inner(self, force, count_waitinglist, user, auth, ignore_date=False, overpaid=False):
         from pretix.base.signals import order_paid
         can_be_paid = self.order._can_be_paid(count_waitinglist=count_waitinglist, ignore_date=ignore_date, force=force)
         if can_be_paid is not True:
@@ -1465,6 +1555,7 @@ class OrderPayment(models.Model):
                 'message': can_be_paid
             }, user=user, auth=auth)
             raise Quota.QuotaExceededException(can_be_paid)
+        status_change = self.order.status != Order.STATUS_PENDING
         self.order.status = Order.STATUS_PAID
         self.order.save(update_fields=['status'])
 
@@ -1478,6 +1569,8 @@ class OrderPayment(models.Model):
         if overpaid:
             self.order.log_action('pretix.event.order.overpaid', {}, user=user, auth=auth)
         order_paid.send(self.order.event, order=self.order)
+        if status_change:
+            self.order.create_transactions()
 
     def fail(self, info=None, user=None, auth=None):
         """
@@ -1530,10 +1623,6 @@ class OrderPayment(models.Model):
         :type mail_text: str
         :raises Quota.QuotaExceededException: if the quota is exceeded and ``force`` is ``False``
         """
-        from pretix.base.services.invoices import (
-            generate_invoice, invoice_qualified,
-        )
-
         with transaction.atomic():
             locked_instance = OrderPayment.objects.select_for_update().get(pk=self.pk)
             if locked_instance.state == self.PAYMENT_STATE_CONFIRMED:
@@ -1577,7 +1666,15 @@ class OrderPayment(models.Model):
             ))
             return
 
-        if (self.order.status == Order.STATUS_PENDING and self.order.expires > now() + timedelta(hours=12)) or not lock:
+        self._mark_order_paid(count_waitinglist, send_mail, force, user, auth, mail_text, ignore_date, lock, payment_sum - refund_sum)
+
+    def _mark_order_paid(self, count_waitinglist=True, send_mail=True, force=False, user=None, auth=None, mail_text='',
+                         ignore_date=False, lock=True, payment_refund_sum=0):
+        from pretix.base.services.invoices import (
+            generate_invoice, invoice_qualified,
+        )
+
+        if (self.order.status == Order.STATUS_PENDING and self.order.expires > now() + timedelta(seconds=LOCK_TIMEOUT * 2)) or not lock:
             # Performance optimization. In this case, there's really no reason to lock everything and an atomic
             # database transaction is more than enough.
             lockfn = NoLockManager
@@ -1585,8 +1682,8 @@ class OrderPayment(models.Model):
             lockfn = self.order.event.lock
 
         with lockfn():
-            self._mark_paid(force, count_waitinglist, user, auth, overpaid=payment_sum - refund_sum > self.order.total,
-                            ignore_date=ignore_date)
+            self._mark_paid_inner(force, count_waitinglist, user, auth, overpaid=payment_refund_sum > self.order.total,
+                                  ignore_date=ignore_date)
 
         invoice = None
         if invoice_qualified(self.order):
@@ -1905,6 +2002,7 @@ class OrderFee(models.Model):
     FEE_TYPE_SHIPPING = "shipping"
     FEE_TYPE_SERVICE = "service"
     FEE_TYPE_CANCELLATION = "cancellation"
+    FEE_TYPE_INSURANCE = "insurance"
     FEE_TYPE_OTHER = "other"
     FEE_TYPE_GIFTCARD = "giftcard"
     FEE_TYPES = (
@@ -1912,6 +2010,7 @@ class OrderFee(models.Model):
         (FEE_TYPE_SHIPPING, _("Shipping fee")),
         (FEE_TYPE_SERVICE, _("Service fee")),
         (FEE_TYPE_CANCELLATION, _("Cancellation fee")),
+        (FEE_TYPE_INSURANCE, _("Insurance fee")),
         (FEE_TYPE_OTHER, _("Other fees")),
         (FEE_TYPE_GIFTCARD, _("Gift card")),
     )
@@ -1953,6 +2052,12 @@ class OrderFee(models.Model):
     def net_value(self):
         return self.value - self.tax_value
 
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        if not self.get_deferred_fields():
+            self.__initial_transaction_key = Transaction.key(self)
+            self.__initial_canceled = self.canceled
+
     def __str__(self):
         if self.description:
             return '{} - {}'.format(self.get_fee_type_display(), self.description)
@@ -1991,6 +2096,15 @@ class OrderFee(models.Model):
         if self.tax_rate is None:
             self._calculate_tax()
         self.order.touch()
+
+        if not self.get_deferred_fields():
+            if Transaction.key(self) != self.__initial_transaction_key or self.canceled != self.__initial_canceled or not self.pk:
+                _transactions_mark_order_dirty(self.order_id, using=kwargs.get('using', None))
+        elif not kwargs.get('force_save_with_deferred_fields', None):
+            _fail("It is unsafe to call save() on an OrderFee with deferred fields since we can't check if you missed "
+                  "creating a transaction. Call save(force_save_with_deferred_fields=True) if you really want to do "
+                  "this.")
+
         return super().save(*args, **kwargs)
 
     def delete(self, **kwargs):
@@ -2005,7 +2119,7 @@ class OrderPosition(AbstractPosition):
     AbstractPosition.
 
     The default ``OrderPosition.objects`` manager only contains fees that are not ``canceled``. If
-    you ant all objects, you need to use ``OrderPosition.all`` instead.
+    you want all objects, you need to use ``OrderPosition.all`` instead.
 
     :param order: The order this position is a part of
     :type order: Order
@@ -2056,6 +2170,12 @@ class OrderPosition(AbstractPosition):
     all = ScopedManager(organizer='order__event__organizer')
     objects = ActivePositionManager()
 
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        if not self.get_deferred_fields():
+            self.__initial_transaction_key = Transaction.key(self)
+            self.__initial_canceled = self.canceled
+
     class Meta:
         verbose_name = _("Order position")
         verbose_name_plural = _("Order positions")
@@ -2099,6 +2219,7 @@ class OrderPosition(AbstractPosition):
             op._calculate_tax()
             op.positionid = i + 1
             op.save()
+            ops.append(op)
             cp_mapping[cartpos.pk] = op
             for answ in cartpos.answers.all():
                 answ.orderposition = op
@@ -2164,6 +2285,14 @@ class OrderPosition(AbstractPosition):
         if not self.pseudonymization_id:
             self.assign_pseudonymization_id()
 
+        if not self.get_deferred_fields():
+            if Transaction.key(self) != self.__initial_transaction_key or self.canceled != self.__initial_canceled or not self.pk:
+                _transactions_mark_order_dirty(self.order_id, using=kwargs.get('using', None))
+        elif not kwargs.get('force_save_with_deferred_fields', None):
+            _fail("It is unsafe to call save() on an OrderFee with deferred fields since we can't check if you missed "
+                  "creating a transaction. Call save(force_save_with_deferred_fields=True) if you really want to do "
+                  "this.")
+
         return super().save(*args, **kwargs)
 
     @scopes_disabled()
@@ -2207,7 +2336,7 @@ class OrderPosition(AbstractPosition):
         :param attach_ical: Attach relevant ICS files
         """
         from pretix.base.services.mail import (
-            SendMailException, mail, render_mail,
+            SendMailException, TolerantDict, mail, render_mail,
         )
 
         if not self.attendee_email:
@@ -2220,6 +2349,7 @@ class OrderPosition(AbstractPosition):
             recipient = self.attendee_email
             try:
                 email_content = render_mail(template, context)
+                subject = str(subject).format_map(TolerantDict(context))
                 mail(
                     recipient, subject, template, context,
                     self.event, self.order.locale, order=self.order, headers=headers, sender=sender,
@@ -2258,6 +2388,151 @@ class OrderPosition(AbstractPosition):
             )
 
 
+class Transaction(models.Model):
+    """
+    Transactions are a data structure that is redundant on the first sight but makes it possible to create good
+    financial reporting.
+
+    To understand this, think of "orders" as something like a contractual relationship between the organizer and the
+    customer which requires to customer to pay some money and the organizer to provide a ticket.
+
+    The ``Order``, ``OrderPosition``, and ``OrderFee`` models combined give a representation of the current contractual
+    status of this relationship, i.e. how much and what is owed. The ``OrderPayment`` and ``OrderRefund`` models indicate
+    the "other side" of the relationship, i.e. how much of the financial obligation has been met so far.
+
+    However, while ``OrderPayment`` and ``OrderRefund`` objects are "final" and no longer change once they reached their
+    final state, ``Order``, ``OrderPosition`` and ``OrderFee`` are highly mutable and can change at any time, e.g. if
+    the customer moves their booking to a different day or a discount is applied retroactively.
+
+    Therefore those models can be used to answer the question "how many tickets of type X have been sold for my event
+    as of today?" but they cannot accurately answer the question "how many tickets of type X have been sold for my event
+    as of last month?" because they lack this kind of historical information.
+
+    Transactions help here because they are "immutable copies" or "modification records" of call positions and fees
+    at the time of their creation and change. They only record data that is usually relevant for financial reporting,
+    such as amounts, prices, products and dates involved. They do not record data like attendee names etc.
+
+    Even before the introduction of the Transaction Model pretix *did* store historical data for auditability in the
+    LogEntry model. However, it's almost impossible to do efficient reporting on that data.
+
+    Transactions should never be generated manually but only through the ``order.create_transactions()``
+    method which should be called **within the same database transaction**.
+
+    The big downside of this approach is that you need to remember to update transaction records every time you change
+    or create orders in new code paths. The mechanism introduced in ``pretix.base.models._transactions`` as well as
+    the ``save()`` methods of ``Order``, ``OrderPosition`` and ``OrderFee`` intends to help you notice if you missed
+    it. The only thing this *doesn't* catch is usage of ``OrderPosition.objects.bulk_create`` (and likewise for
+    ``bulk_update`` and ``OrderFee``).
+
+    :param id: ID of the transaction
+    :param order: Order the transaction belongs to
+    :param datetime: Date and time of the transaction
+    :param migrated: Whether this object was reconstructed because the order was created before transactions where introduced
+    :param positionid: Affected Position ID, in case this transaction represents a change in an order position
+    :param count: An amount, multiplicator for price etc. For order positions this can *currently* only be -1 or +1, for
+                  fees it can also be more in special cases
+    :param item: ``Item``, in case this transaction represents a change in an order position
+    :param variation: ``ItemVariation``, in case this transaction represents a change in an order position
+    :param subevent: ``subevent``, in case this transaction represents a change in an order position
+    :param price: Price of the changed position
+    :param tax_rate: Tax rate of the changed position
+    :param tax_rule: Used tax rule
+    :param tax_value: Tax value in event currency
+    :param fee_type: Fee type code in case this transaction represents a change in an order fee
+    :param internal_type: Internal fee type in case this transaction represents a change in an order fee
+    """
+    id = models.BigAutoField(primary_key=True)
+    order = models.ForeignKey(
+        Order,
+        verbose_name=_("Order"),
+        related_name='transactions',
+        on_delete=models.PROTECT
+    )
+    created = models.DateTimeField(
+        auto_now_add=True,
+        db_index=True,
+    )
+    datetime = models.DateTimeField(
+        verbose_name=_("Date"),
+        db_index=True,
+    )
+    migrated = models.BooleanField(
+        default=False
+    )
+    positionid = models.PositiveIntegerField(default=1, null=True, blank=True)
+    count = models.IntegerField(
+        default=1
+    )
+    item = models.ForeignKey(
+        Item,
+        null=True, blank=True,
+        verbose_name=_("Item"),
+        on_delete=models.PROTECT
+    )
+    variation = models.ForeignKey(
+        ItemVariation,
+        null=True, blank=True,
+        verbose_name=_("Variation"),
+        on_delete=models.PROTECT
+    )
+    subevent = models.ForeignKey(
+        SubEvent,
+        null=True, blank=True,
+        on_delete=models.PROTECT,
+        verbose_name=pgettext_lazy("subevent", "Date"),
+    )
+    price = models.DecimalField(
+        decimal_places=2, max_digits=10,
+        verbose_name=_("Price")
+    )
+    tax_rate = models.DecimalField(
+        max_digits=7, decimal_places=2,
+        verbose_name=_('Tax rate')
+    )
+    tax_rule = models.ForeignKey(
+        'TaxRule',
+        on_delete=models.PROTECT,
+        null=True, blank=True
+    )
+    tax_value = models.DecimalField(
+        max_digits=10, decimal_places=2,
+        verbose_name=_('Tax value')
+    )
+    fee_type = models.CharField(
+        max_length=100, choices=OrderFee.FEE_TYPES, null=True, blank=True
+    )
+    internal_type = models.CharField(max_length=255, null=True, blank=True)
+
+    class Meta:
+        ordering = 'datetime', 'pk'
+
+    def save(self, *args, **kwargs):
+        if not self.fee_type and not self.item:
+            raise ValidationError('Should set either item or fee type')
+        return super().save(*args, **kwargs)
+
+    @staticmethod
+    def key(obj):
+        if isinstance(obj, Transaction):
+            return (obj.positionid, obj.item_id, obj.variation_id, obj.subevent_id, obj.price, obj.tax_rate,
+                    obj.tax_rule_id, obj.tax_value, obj.fee_type, obj.internal_type)
+        elif isinstance(obj, OrderPosition):
+            return (obj.positionid, obj.item_id, obj.variation_id, obj.subevent_id, obj.price, obj.tax_rate,
+                    obj.tax_rule_id, obj.tax_value, None, None)
+        elif isinstance(obj, OrderFee):
+            return (None, None, None, None, obj.value, obj.tax_rate,
+                    obj.tax_rule_id, obj.tax_value, obj.fee_type, obj.internal_type)
+        raise ValueError('invalid state')  # noqa
+
+    @property
+    def full_price(self):
+        return self.price * self.count
+
+    @property
+    def full_tax_value(self):
+        return self.tax_value * self.count
+
+
 class CartPosition(AbstractPosition):
     """
     A cart position is similar to an order line, except that it is not
@@ -2296,7 +2571,6 @@ class CartPosition(AbstractPosition):
         max_digits=10, decimal_places=2,
         null=True, blank=True
     )
-    is_bundled = models.BooleanField(default=False)
 
     objects = ScopedManager(organizer='event__organizer')
 
@@ -2329,6 +2603,12 @@ class CartPosition(AbstractPosition):
 class InvoiceAddress(models.Model):
     last_modified = models.DateTimeField(auto_now=True)
     order = models.OneToOneField(Order, null=True, blank=True, related_name='invoice_address', on_delete=models.CASCADE)
+    customer = models.ForeignKey(
+        Customer,
+        related_name='invoice_addresses',
+        null=True, blank=True,
+        on_delete=models.CASCADE
+    )
     is_business = models.BooleanField(default=False, verbose_name=_('Business customer'))
     company = models.CharField(max_length=255, blank=True, verbose_name=_('Company name'))
     name_cached = models.CharField(max_length=255, verbose_name=_('Full name'), blank=True)
@@ -2340,8 +2620,7 @@ class InvoiceAddress(models.Model):
     country = FastCountryField(verbose_name=_('Country'), blank=False, blank_label=_('Select country'),
                                countries=CachedCountries)
     state = models.CharField(max_length=255, verbose_name=pgettext_lazy('address', 'State'), blank=True)
-    vat_id = models.CharField(max_length=255, blank=True, verbose_name=_('VAT ID'),
-                              help_text=_('Only for business customers within the EU.'))
+    vat_id = models.CharField(max_length=255, blank=True, verbose_name=_('VAT ID'))
     vat_id_validated = models.BooleanField(default=False)
     custom_field = models.CharField(max_length=255, null=True, blank=True)
     internal_reference = models.TextField(
@@ -2355,6 +2634,7 @@ class InvoiceAddress(models.Model):
     )
 
     objects = ScopedManager(organizer='order__event__organizer')
+    profiles = ScopedManager(organizer='customer__organizer')
 
     def save(self, **kwargs):
         if self.order:
@@ -2367,6 +2647,20 @@ class InvoiceAddress(models.Model):
             self.name_parts = {}
         super().save(**kwargs)
 
+    def describe(self):
+        parts = [
+            self.company,
+            self.name,
+            self.street,
+            (self.zipcode or '') + ' ' + (self.city or '') + ' ' + (self.state_for_address or ''),
+            self.country.name,
+            self.vat_id,
+            self.custom_field,
+            self.internal_reference,
+            (_('Beneficiary') + ': ' + self.beneficiary) if self.beneficiary else '',
+        ]
+        return '\n'.join([str(p).strip() for p in parts if p and str(p).strip()])
+
     @property
     def is_empty(self):
         return (
@@ -2402,6 +2696,30 @@ class InvoiceAddress(models.Model):
             raise TypeError("Invalid name given.")
         return scheme['concatenation'](self.name_parts).strip()
 
+    def for_js(self):
+        d = {}
+
+        if self.name_parts:
+            if '_scheme' in self.name_parts:
+                scheme = PERSON_NAME_SCHEMES[self.name_parts['_scheme']]
+                for i, (k, l, w) in enumerate(scheme['fields']):
+                    d[f'name_parts_{i}'] = self.name_parts.get(k) or ''
+
+        d.update({
+            'company': self.company,
+            'is_business': self.is_business,
+            'street': self.street,
+            'zipcode': self.zipcode,
+            'city': self.city,
+            'country': str(self.country) if self.country else None,
+            'state': str(self.state) if self.state else None,
+            'vat_id': self.vat_id,
+            'custom_field': self.custom_field,
+            'internal_reference': self.internal_reference,
+            'beneficiary': self.beneficiary,
+        })
+        return d
+
 
 def cachedticket_name(instance, filename: str) -> str:
     secret = get_random_string(length=16, allowed_chars=string.ascii_letters + string.digits)

src/pretix/base/models/tax.py

@@ -25,7 +25,6 @@ from decimal import Decimal
 from django.core.exceptions import ValidationError
 from django.db import models
 from django.utils.formats import localize
-from django.utils.timezone import get_current_timezone, now
 from django.utils.translation import gettext_lazy as _, pgettext
 from i18nfield.fields import I18nCharField
 from i18nfield.strings import LazyI18nString
@@ -93,7 +92,7 @@ TAXED_ZERO = TaxedPrice(
 
 EU_COUNTRIES = {
     'AT', 'BE', 'BG', 'HR', 'CY', 'CZ', 'DK', 'EE', 'FI', 'FR', 'DE', 'GR', 'HU', 'IE', 'IT', 'LV', 'LT', 'LU', 'MT',
-    'NL', 'PL', 'PT', 'RO', 'SK', 'SI', 'ES', 'SE', 'GB'
+    'NL', 'PL', 'PT', 'RO', 'SK', 'SI', 'ES', 'SE',
 }
 EU_CURRENCIES = {
     'BG': 'BGN',
@@ -106,17 +105,21 @@ EU_CURRENCIES = {
     'RO': 'RON',
     'SE': 'SEK'
 }
+VAT_ID_COUNTRIES = EU_COUNTRIES | {'CH'}
 
 
 def is_eu_country(cc):
     cc = str(cc)
-    if cc == 'GB':
-        return now().astimezone(get_current_timezone()).year <= 2020
-    else:
-        return cc in EU_COUNTRIES
+    return cc in EU_COUNTRIES
+
+
+def ask_for_vat_id(cc):
+    cc = str(cc)
+    return cc in VAT_ID_COUNTRIES
 
 
 def cc_to_vat_prefix(country_code):
+    country_code = str(country_code)
     if country_code == 'GR':
         return 'EL'
     return country_code
@@ -162,10 +165,13 @@ class TaxRule(LoggedModel):
         pass
 
     def allow_delete(self):
-        from pretix.base.models.orders import OrderFee, OrderPosition
+        from pretix.base.models.orders import (
+            OrderFee, OrderPosition, Transaction,
+        )
 
         return (
-            not OrderFee.objects.filter(tax_rule=self, order__event=self.event).exists()
+            not Transaction.objects.filter(tax_rule=self, order__event=self.event).exists()
+            and not OrderFee.objects.filter(tax_rule=self, order__event=self.event).exists()
             and not OrderPosition.all.filter(tax_rule=self, order__event=self.event).exists()
             and not self.event.items.filter(tax_rule=self).exists()
             and self.event.settings.tax_rate_default != self

src/pretix/base/models/vouchers.py

@@ -38,7 +38,7 @@ from decimal import ROUND_HALF_UP, Decimal
 from django.conf import settings
 from django.core.exceptions import ValidationError
 from django.core.validators import MinLengthValidator
-from django.db import models
+from django.db import connection, models
 from django.db.models import F, OuterRef, Q, Subquery, Sum
 from django.db.models.functions import Coalesce
 from django.utils.crypto import get_random_string
@@ -74,6 +74,55 @@ def generate_code(prefix=None):
             return code
 
 
+def generate_codes(organizer, num=1, prefix=None):
+    codes = set()
+    batch_size = 500
+    if 'postgres' in settings.DATABASES['default']['ENGINE']:
+        batch_size = 5_000
+
+    """
+    We're trying to check if any of the requested codes already exists in the database. Generally, this is a
+
+        SELECT code FROM voucher WHERE code IN (…)
+
+    query. However, it turns out that this query get's rather slow if an organizer has lots of vouchers, even
+    with a organizer with just over 50_000 vouchers, we've seen that creating 20_000 new voucher codes took
+    just over 30 seconds. There's another way of doing this query on PostgreSQL, which is joining with a
+    temporary table
+
+        SELECT code FROM voucher INNER JOIN (VALUES …) vals(v) ON (code = v)
+
+    This is significantly faster, inserting 20_000 vouchers now takes 2-3s instead of 31s on the same dataset.
+    It's still slow, and removing the JOIN to the event table doesn't significantly speed it up. We might need
+    an entirely different approach at some point.
+    """
+
+    while len(codes) < num:
+        new_codes = set()
+        for i in range(min(num - len(codes), batch_size)):  # Work around SQLite's SQLITE_MAX_VARIABLE_NUMBER
+            new_codes.add(_generate_random_code(prefix=prefix))
+
+        if 'postgres' in settings.DATABASES['default']['ENGINE']:
+            with connection.cursor() as cursor:
+                args = list(new_codes) + [organizer.pk]
+                tmptable = "VALUES " + (", ".join(['(%s)'] * len(new_codes)))
+                cursor.execute(
+                    f'SELECT code '
+                    f'FROM "{Voucher._meta.db_table}" '
+                    f'INNER JOIN ({tmptable}) vals(v) ON ("{Voucher._meta.db_table}"."code" = "v")'
+                    f'INNER JOIN "{Event._meta.db_table}" ON ("{Voucher._meta.db_table}"."event_id" = "{Event._meta.db_table}"."id") '
+                    f'WHERE "{Event._meta.db_table}"."organizer_id" = %s',
+                    args
+                )
+                for row in cursor.fetchall():
+                    new_codes.remove(row[0])
+        else:
+            new_codes -= set([v['code'] for v in Voucher.objects.filter(code__in=new_codes).values('code')])
+
+        codes |= new_codes
+    return list(codes)
+
+
 class Voucher(LoggedModel):
     """
     A Voucher can reserve ticket quota or allow special prices.

src/pretix/base/models/waitinglist.py

@@ -21,8 +21,9 @@
 #
 from datetime import timedelta
 
-from django.core.exceptions import ValidationError
+from django.core.exceptions import ObjectDoesNotExist, ValidationError
 from django.db import models, transaction
+from django.db.models import F, Q, Sum
 from django.utils.timezone import now
 from django.utils.translation import gettext_lazy as _, pgettext_lazy
 from django_scopes import ScopedManager
@@ -114,9 +115,12 @@ class WaitingListEntry(LoggedModel):
         return '%s waits for %s' % (str(self.email), str(self.item))
 
     def clean(self):
-        WaitingListEntry.clean_duplicate(self.email, self.item, self.variation, self.subevent, self.pk)
-        WaitingListEntry.clean_itemvar(self.event, self.item, self.variation)
-        WaitingListEntry.clean_subevent(self.event, self.subevent)
+        try:
+            WaitingListEntry.clean_duplicate(self.email, self.item, self.variation, self.subevent, self.pk)
+            WaitingListEntry.clean_itemvar(self.event, self.item, self.variation)
+            WaitingListEntry.clean_subevent(self.event, self.subevent)
+        except ObjectDoesNotExist:
+            raise ValidationError('Invalid input')
 
     def save(self, *args, **kwargs):
         update_fields = kwargs.get('update_fields', [])
@@ -147,6 +151,34 @@ class WaitingListEntry(LoggedModel):
         )
         if availability[1] is None or availability[1] < 1:
             raise WaitingListException(_('This product is currently not available.'))
+
+        ev = self.subevent or self.event
+        if ev.seat_category_mappings.filter(product=self.item).exists():
+            # Generally, we advertise the waiting list to be based on quotas only. This makes it dangerous
+            # to use in combination with seating plans. If your event has 50 seats and a quota of 50 and
+            # default settings, everything is fine and the waiting list will work as usual. However, as soon
+            # as those two numbers diverge, either due to misconfiguration or due to intentional features such
+            # as our COVID-19 minimum distance feature, things get ugly. Theoretically, there could be
+            # significant quota available but not a single seat! The waiting list would happily send out vouchers
+            # which do not work at all. Generally, we consider this a "known bug" and not fixable with the current
+            # design of the waiting list and seating features.
+            # However, we've put in a simple safeguard that makes sure the waiting list on its own does not screw
+            # everything up. Specifically, we will not send out vouchers if the number of available seats is less
+            # than the number of valid vouchers *issued through the waiting list*. Things can still go wrong due to
+            # manually created vouchers, manually blocked seats or the minimum distance feature,  but this reduces
+            # the possible damage a bit.
+            num_free_seats_for_product = ev.free_seats().filter(product=self.item).count()
+            num_valid_vouchers_for_product = self.event.vouchers.filter(
+                Q(valid_until__isnull=True) | Q(valid_until__gte=now()),
+                block_quota=True,
+                item_id=self.item_id,
+                subevent_id=self.subevent_id,
+                waitinglistentries__isnull=False
+            ).aggregate(free=Sum(F('max_usages') - F('redeemed')))['free'] or 0
+            free_seats = num_free_seats_for_product - num_valid_vouchers_for_product
+            if not free_seats:
+                raise WaitingListException(_('No seat with this product is currently available.'))
+
         if self.voucher:
             raise WaitingListException(_('A voucher has already been sent to this person.'))
         if '@' not in self.email:

src/pretix/base/orderimport.py

@@ -36,6 +36,8 @@ from django.utils.translation import (
 from django_countries import countries
 from django_countries.fields import Country
 from i18nfield.strings import LazyI18nString
+from phonenumber_field.phonenumber import to_python
+from phonenumbers import SUPPORTED_REGIONS
 
 from pretix.base.channels import get_all_sales_channels
 from pretix.base.forms.questions import guess_country
@@ -156,6 +158,29 @@ class EmailColumn(ImportColumn):
         order.email = value
 
 
+class PhoneColumn(ImportColumn):
+    identifier = 'phone'
+    verbose_name = gettext_lazy('Phone number')
+
+    def clean(self, value, previous_values):
+        if value:
+            if self.event.settings.region in SUPPORTED_REGIONS:
+                region = self.event.settings.region
+            elif self.event.settings.locale[:2].upper() in SUPPORTED_REGIONS:
+                region = self.event.settings.locale[:2].upper()
+            else:
+                region = None
+
+            phone_number = to_python(value, region)
+            if not phone_number or not phone_number.is_valid():
+                raise ValidationError(_('Enter a valid phone number.'))
+            return phone_number
+        return value
+
+    def assign(self, value, order, position, invoice_address, **kwargs):
+        order.phone = value
+
+
 class SubeventColumn(ImportColumn):
     identifier = 'subevent'
     verbose_name = pgettext_lazy('subevents', 'Date')
@@ -653,9 +678,12 @@ class SeatColumn(ImportColumn):
         if value:
             try:
                 value = Seat.objects.get(
+                    event=self.event,
                     seat_guid=value,
                     subevent=previous_values.get('subevent')
                 )
+            except Seat.MultipleObjectsReturned:
+                raise ValidationError(_('Multiple matching seats were found.'))
             except Seat.DoesNotExist:
                 raise ValidationError(_('No matching seat was found.'))
             if not value.is_available() or value in self._cached:
@@ -756,6 +784,7 @@ def get_all_columns(event):
         default.append(SubeventColumn(event))
     default += [
         EmailColumn(event),
+        PhoneColumn(event),
         ItemColumn(event),
         Variation(event),
         InvoiceAddressCompany(event),

src/pretix/base/payment.py

@@ -703,7 +703,7 @@ class BasePaymentProvider:
             try:
                 ia = order.invoice_address
             except InvoiceAddress.DoesNotExist:
-                return True
+                pass
             else:
                 if str(ia.country) not in restricted_countries:
                     return False

src/pretix/base/pdf.py

@@ -99,6 +99,11 @@ DEFAULT_VARIABLES = OrderedDict((
         "editor_sample": "1",
         "evaluate": lambda orderposition, order, event: str(orderposition.positionid)
     }),
+    ("order_positionid", {
+        "label": _("Order code and position number"),
+        "editor_sample": "A1B2C-1",
+        "evaluate": lambda orderposition, order, event: f"{orderposition.order.code}-{orderposition.positionid}"
+    }),
     ("item", {
         "label": _("Product name"),
         "editor_sample": _("Sample product"),
@@ -429,7 +434,7 @@ def images_from_questions(sender, *args, **kwargs):
             except IndexError:
                 pass
         else:
-            a = op.answers.filter(question_id=question_id).first()
+            a = op.answers.filter(question_id=question_id).first() or a
 
         if not a or not a.file or not any(a.file.name.lower().endswith(e) for e in (".jpg", ".jpeg", ".png", ".gif", ".bmp", ".tif", ".tiff")):
             return None
@@ -469,7 +474,7 @@ def variables_from_questions(sender, *args, **kwargs):
             except IndexError:
                 pass
         else:
-            a = op.answers.filter(question_id=question_id).first()
+            a = op.answers.filter(question_id=question_id).first() or a
 
         if not a:
             return ""

src/pretix/base/services/cart.py

@@ -283,13 +283,16 @@ class CartManager:
                 if op.item.require_voucher and op.voucher is None:
                     raise CartError(error_messages['voucher_required'])
 
-                if op.item.hide_without_voucher and (op.voucher is None or not op.voucher.show_hidden_items):
+                if (
+                    (op.item.hide_without_voucher or (op.variation and op.variation.hide_without_voucher)) and
+                    (op.voucher is None or not op.voucher.show_hidden_items)
+                ):
                     raise CartError(error_messages['voucher_required'])
 
-            if not op.item.is_available() or (op.variation and not op.variation.active):
+            if not op.item.is_available() or (op.variation and not op.variation.is_available()):
                 raise CartError(error_messages['unavailable'])
 
-            if self._sales_channel not in op.item.sales_channels:
+            if self._sales_channel not in op.item.sales_channels or (op.variation and self._sales_channel not in op.variation.sales_channels):
                 raise CartError(error_messages['unavailable'])
 
             if op.subevent and op.item.pk in op.subevent.item_overrides and not op.subevent.item_overrides[op.item.pk].is_available():

src/pretix/base/services/checkin.py

@@ -39,7 +39,7 @@ import dateutil
 import dateutil.parser
 import pytz
 from django.core.files import File
-from django.db import transaction
+from django.db import IntegrityError, transaction
 from django.db.models import (
     BooleanField, Count, ExpressionWrapper, F, IntegerField, OuterRef, Q,
     Subquery, Value,
@@ -512,6 +512,21 @@ class RequiredQuestionsError(Exception):
 
 
 def _save_answers(op, answers, given_answers):
+    def _create_answer(question, answer):
+        try:
+            return op.answers.create(question=question, answer=answer)
+        except IntegrityError:
+            # Since we prefill ``field.answer`` at form creation time, there's a possible race condition
+            # here if the user submits their scan a second time while the first one is still running,
+            # thus leading to duplicate QuestionAnswer objects. Since Django doesn't support UPSERT, the "proper"
+            # fix would be a transaction with select_for_update(), or at least fetching using get_or_create here
+            # again. However, both of these approaches have a significant performance overhead for *all* requests,
+            # while the issue happens very very rarely. So we opt for just catching the error and retrying properly.
+            qa = op.answers.get(question=question)
+            qa.answer = answer
+            qa.save(update_fields=['answer'])
+            qa.options.clear()
+
     written = False
     for q, a in given_answers.items():
         if not a:
@@ -528,7 +543,7 @@ def _save_answers(op, answers, given_answers):
                 written = True
                 qa.options.clear()
             else:
-                qa = op.answers.create(question=q, answer=str(a.answer))
+                qa = _create_answer(question=q, answer=str(a.answer))
             qa.options.add(a)
         elif isinstance(a, list):
             if q in answers:
@@ -538,13 +553,13 @@ def _save_answers(op, answers, given_answers):
                 written = True
                 qa.options.clear()
             else:
-                qa = op.answers.create(question=q, answer=", ".join([str(o) for o in a]))
+                qa = _create_answer(question=q, answer=", ".join([str(o) for o in a]))
             qa.options.add(*a)
         elif isinstance(a, File):
             if q in answers:
                 qa = answers[q]
             else:
-                qa = op.answers.create(question=q, answer=str(a))
+                qa = _create_answer(question=q, answer=str(a))
             qa.file.save(os.path.basename(a.name), a, save=False)
             qa.answer = 'file://' + qa.file.name
             qa.save()
@@ -555,7 +570,7 @@ def _save_answers(op, answers, given_answers):
                 qa.answer = str(a)
                 qa.save()
             else:
-                op.answers.create(question=q, answer=str(a))
+                _create_answer(question=q, answer=str(a))
             written = True
 
     if written:
@@ -567,7 +582,7 @@ def _save_answers(op, answers, given_answers):
 def perform_checkin(op: OrderPosition, clist: CheckinList, given_answers: dict, force=False,
                     ignore_unpaid=False, nonce=None, datetime=None, questions_supported=True,
                     user=None, auth=None, canceled_supported=False, type=Checkin.TYPE_ENTRY,
-                    raw_barcode=None):
+                    raw_barcode=None, from_revoked_secret=False):
     """
     Create a checkin for this particular order position and check-in list. Fails with CheckInError if the check in is
     not valid at this time.
@@ -582,6 +597,11 @@ def perform_checkin(op: OrderPosition, clist: CheckinList, given_answers: dict,
     :param nonce: A random nonce to prevent race conditions.
     :param datetime: The datetime of the checkin, defaults to now.
     """
+
+    # !!!!!!!!!
+    # Update doc/images/checkin_online.puml if you make substantial changes here!
+    # !!!!!!!!!
+
     dt = datetime or now()
 
     if op.canceled or op.order.status not in (Order.STATUS_PAID, Order.STATUS_PENDING):
@@ -649,15 +669,16 @@ def perform_checkin(op: OrderPosition, clist: CheckinList, given_answers: dict,
         if isinstance(auth, Device):
             device = auth
 
-        last_ci = op.checkins.order_by('-datetime').filter(list=clist).only('type', 'nonce').first()
+        last_cis = list(op.checkins.order_by('-datetime').filter(list=clist).only('type', 'nonce'))
         entry_allowed = (
             type == Checkin.TYPE_EXIT or
             clist.allow_multiple_entries or
-            last_ci is None or
-            (clist.allow_entry_after_exit and last_ci.type == Checkin.TYPE_EXIT)
+            not last_cis or
+            all(c.type == Checkin.TYPE_EXIT for c in last_cis) or
+            (clist.allow_entry_after_exit and last_cis[0].type == Checkin.TYPE_EXIT)
         )
 
-        if nonce and ((last_ci and last_ci.nonce == nonce) or op.checkins.filter(type=type, list=clist, device=device, nonce=nonce).exists()):
+        if nonce and ((last_cis and last_cis[0].nonce == nonce) or op.checkins.filter(type=type, list=clist, device=device, nonce=nonce).exists()):
             return
 
         if entry_allowed or force:
@@ -669,7 +690,7 @@ def perform_checkin(op: OrderPosition, clist: CheckinList, given_answers: dict,
                 device=device,
                 gate=device.gate if device else None,
                 nonce=nonce,
-                forced=force and not entry_allowed,
+                forced=force and (not entry_allowed or from_revoked_secret),
                 raw_barcode=raw_barcode,
             )
             op.order.log_action('pretix.event.checkin', data={
@@ -715,7 +736,11 @@ def process_exit_all(sender, **kwargs):
         exit_all_at__isnull=False
     ).select_related('event', 'event__organizer')
     for cl in qs:
-        for p in cl.positions_inside:
+        positions = cl.positions_inside.filter(
+            Q(last_exit__isnull=True) | Q(last_exit__lte=cl.exit_all_at),
+            last_entry__lte=cl.exit_all_at,
+        )
+        for p in positions:
             with scope(organizer=cl.event.organizer):
                 ci = Checkin.objects.create(
                     position=p, list=cl, auto_checked_in=True, type=Checkin.TYPE_EXIT, datetime=cl.exit_all_at
@@ -727,6 +752,9 @@ def process_exit_all(sender, **kwargs):
             cl.event.settings.delete(f'autocheckin_dst_hack_{cl.pk}')
         try:
             cl.exit_all_at = make_aware(datetime.combine(d.date() + timedelta(days=1), d.time()), cl.event.timezone)
+        except pytz.exceptions.AmbiguousTimeError:
+            cl.exit_all_at = make_aware(datetime.combine(d.date() + timedelta(days=1), d.time()), cl.event.timezone,
+                                        is_dst=False)
         except pytz.exceptions.NonExistentTimeError:
             cl.event.settings.set(f'autocheckin_dst_hack_{cl.pk}', True)
             d += timedelta(hours=1)