Fix #1066 -- Change installation tutorials to PostgreSQL

This is the recommended database server so this documentation should use that

doc/admin/installation/docker_smallscale.rst

@@ -58,16 +58,29 @@ Database
 --------
 
 Next, we need a database and a database user. We can create these with any kind of database managing tool or directly on
-our database's shell, e.g. for MySQL::
+our database's shell. For PostgreSQL, we would do::
 
-    $ mysql -u root -p
+    # sudo -u postgres createuser -P pretix
-    mysql> CREATE DATABASE pretix DEFAULT CHARACTER SET utf8mb4 DEFAULT COLLATE utf8mb4_unicode_ci;
+    # sudo -u postgres createdb -O pretix pretix
-    mysql> GRANT ALL PRIVILEGES ON pretix.* TO pretix@'localhost' IDENTIFIED BY '*********';
-    mysql> FLUSH PRIVILEGES;
 
-Replace the asterisks with a password of your own. For MySQL, we will use a unix domain socket to connect to the
+Make sure that your database listens on the network. If PostgreSQL on the same same host as docker, but not inside a docker container, we recommend that you just listen on the Docker interface by changing the following line in ``/etc/postgresql/<version>/main/postgresql.conf``::
-database. For PostgreSQL, be sure to configure the interface binding and your firewall so that the docker container
+
-can reach PostgreSQL.
+    listen_addresses = 'localhost,172.17.0.1'
+
+You also need to add a new line to ``/etc/postgresql/<version>/main/pg_hba.conf`` to allow network connections to this user and database::
+
+    host    pretix          pretix          172.17.0.1/16           md5
+
+Restart PostgreSQL after you changed these files::
+
+    # systemctl restart postgresql
+
+If you have a firewall running, you should also make sure that port 5432 is reachable from the ``172.17.0.1/16`` subnet.
+
+For MySQL, you can either also use network-based connections or mount the ``/var/run/mysqld/mysqld.sock`` socket into the docker container.
+When using MySQL, make sure you set the character set of the database to ``utf8mb4``, e.g. like this::
+
+    mysql > CREATE DATABASE pretix DEFAULT CHARACTER SET utf8mb4 DEFAULT COLLATE utf8mb4_unicode_ci;
 
 Redis
 -----
@@ -114,13 +127,16 @@ Fill the configuration file ``/etc/pretix/pretix.cfg`` with the following conten
     datadir=/data
 
     [database]
-    ; Replace mysql with postgresql_psycopg2 for PostgreSQL
+    ; Replace postgresql with mysql for MySQL
-    backend=mysql
+    backend=postgresql
     name=pretix
     user=pretix
+    ; Replace with the password you chose above
     password=*********
-    ; Replace with host IP address for PostgreSQL
+    ; In most docker setups, 172.17.0.1 is the address of the docker host. Adjuts
-    host=/var/run/mysqld/mysqld.sock
+    ; this to wherever your database is running, e.g. the name of a linked container
+    ; or of a mounted MySQL socket.
+    host=172.17.0.1
 
     [mail]
     ; See config file documentation for more options
@@ -164,14 +180,15 @@ named ``/etc/systemd/system/pretix.service`` with the following content::
         -v /var/pretix-data:/data \
         -v /etc/pretix:/etc/pretix \
         -v /var/run/redis:/var/run/redis \
-        -v /var/run/mysqld:/var/run/mysqld \
         pretix/standalone:stable all
     ExecStop=/usr/bin/docker stop %n
 
     [Install]
     WantedBy=multi-user.target
 
-You can leave the MySQL socket volume out if you're using PostgreSQL. You can now run the following commands
+When using MySQL and socket mounting, you'll need the additional flag ``-v /var/run/mysqld:/var/run/mysqld`` in the command.
+
+You can now run the following commands
 to enable and start the service::
 
     # systemctl daemon-reload

doc/admin/installation/manual_smallscale.rst

@@ -50,21 +50,27 @@ Database
 --------
 
 Having the database server installed, we still need a database and a database user. We can create these with any kind
-of database managing tool or directly on our database's shell, e.g. for MySQL::
+of database managing tool or directly on our database's shell. For PostgreSQL, we would do::
 
-    $ mysql -u root -p
+    # sudo -u postgres createuser pretix
-    mysql> CREATE DATABASE pretix DEFAULT CHARACTER SET utf8mb4 DEFAULT COLLATE utf8mb4_unicode_ci;
+    # sudo -u postgres createdb -O pretix pretix
-    mysql> GRANT ALL PRIVILEGES ON pretix.* TO pretix@'localhost' IDENTIFIED BY '*********';
+
-    mysql> FLUSH PRIVILEGES;
+When using MySQL, make sure you set the character set of the database to ``utf8mb4``, e.g. like this::
+
+    mysql > CREATE DATABASE pretix DEFAULT CHARACTER SET utf8mb4 DEFAULT COLLATE utf8mb4_unicode_ci;
 
 Package dependencies
 --------------------
 
 To build and run pretix, you will need the following debian packages::
 
-    # apt-get install git build-essential python-dev python-virtualenv python3 python3-pip \
+    # 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 libmysqlclient-dev libjpeg-dev libopenjp2-7-dev
+                      gettext libpq-dev libmariadbclient-dev libjpeg-dev libopenjp2-7-dev
+
+.. note:: Python 3.7 is not yet supported, so if you run a very recent OS, make sure to get
+          Python 3.6 from somewhere. You can check the current state of things in our
+          `Python 3.7 issue`_.
 
 Config file
 -----------
@@ -85,13 +91,18 @@ Fill the configuration file ``/etc/pretix/pretix.cfg`` with the following conten
     datadir=/var/pretix/data
 
     [database]
-    ; Replace mysql with postgresql_psycopg2 for PostgreSQL
+    ; For MySQL, replace with "mysql"
-    backend=mysql
+    backend=postgresql
     name=pretix
     user=pretix
-    password=*********
+    ; For MySQL, enter the user password. For PostgreSQL on the same host,
-    ; Replace with host IP address for PostgreSQL
+    ; we don't need one because we can use peer authentification if our
-    host=/var/run/mysqld/mysqld.sock
+    ; PostgreSQL user matches our unix user.
+    password=
+    ; For MySQL, use local socket, e.g. /var/run/mysqld/mysqld.sock
+    ; For a remote host, supply an IP address
+    ; For local postgres authentication, you can leave it empty
+    host=
 
     [mail]
     ; See config file documentation for more options
@@ -115,14 +126,14 @@ Now we will install pretix itself. The following steps are to be executed as the
 actually install pretix, we will create a virtual environment to isolate the python packages from your global
 python installation::
 
-    $ virtualenv -p python3 /var/pretix/venv
+    $ python3 -m venv /var/pretix/venv
     $ source /var/pretix/venv/bin/activate
     (venv)$ pip3 install -U pip setuptools wheel
 
-We now install pretix, its direct dependencies and gunicorn. Replace ``mysql`` with ``postgres`` in the following
+We now install pretix, its direct dependencies and gunicorn. Replace ``postgres`` with ``mysql`` in the following
-command if you're running PostgreSQL::
+command if you're running MySQL::
 
-    (venv)$ pip3 install "pretix[mysql]" gunicorn
+    (venv)$ pip3 install "pretix[postgres]" gunicorn
 
 Note that you need Python 3.5 or newer. You can find out your Python version using ``python -V``.
 
@@ -268,10 +279,10 @@ 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
-``mysql`` with ``postgres`` if necessary)::
+``postgres`` with ``mysql`` if necessary)::
 
     $ source /var/pretix/venv/bin/activate
-    (venv)$ pip3 install -U pretix[mysql] gunicorn
+    (venv)$ pip3 install -U pretix[postgres] gunicorn
     (venv)$ python -m pretix migrate
     (venv)$ python -m pretix rebuild
     (venv)$ python -m pretix updatestyles
@@ -303,3 +314,4 @@ example::
 .. _redis: https://blog.programster.org/debian-8-install-redis-server/
 .. _ufw: https://en.wikipedia.org/wiki/Uncomplicated_Firewall
 .. _strong encryption settings: https://mozilla.github.io/server-side-tls/ssl-config-generator/
+.. _Python 3.7 issue: https://github.com/pretix/pretix/issues/1025