Apply suggestions from code review

Co-authored-by: Raphael Michel <mail@raphaelmichel.de>

Dockerfile

@@ -31,6 +31,7 @@ RUN apt-get update && \
     mkdir /etc/pretix && \
     mkdir /data && \
     useradd -ms /bin/bash -d /pretix -u 15371 pretixuser && \
+    chmod 0755 /pretix && \
     echo 'pretixuser ALL=(ALL) NOPASSWD:SETENV: /usr/bin/supervisord' >> /etc/sudoers && \
     mkdir /static && \
     mkdir /etc/supervisord

doc/api/resources/item_program_times.rst

@@ -16,6 +16,7 @@ Field                                 Type                       Description
 id                                    integer                    Internal ID of the program time
 start                                 datetime                   The start date time for this program time slot.
 end                                   datetime                   The end date time for this program time slot.
+location                              multi-lingual string       The program time slot's location (or ``null``)
 ===================================== ========================== =======================================================
 
 .. versionchanged:: TODO
@@ -54,17 +55,20 @@ Endpoints
             {
                "id": 2,
                "start": "2025-08-14T22:00:00Z",
-               "end": "2025-08-15T00:00:00Z"
+               "end": "2025-08-15T00:00:00Z",
+               "location": null
             },
             {
                "id": 3,
                "start": "2025-08-12T22:00:00Z",
-               "end": "2025-08-13T22:00:00Z"
+               "end": "2025-08-13T22:00:00Z",
+               "location": null
             },
             {
                "id": 14,
                "start": "2025-08-15T22:00:00Z",
-               "end": "2025-08-17T22:00:00Z"
+               "end": "2025-08-17T22:00:00Z",
+               "location": null
             }
         ]
       }
@@ -99,7 +103,8 @@ Endpoints
       {
          "id": 1,
          "start": "2025-08-15T22:00:00Z",
-         "end": "2025-10-27T23:00:00Z"
+         "end": "2025-10-27T23:00:00Z",
+         "location": null
       }
 
    :param organizer: The ``slug`` field of the organizer to fetch
@@ -125,7 +130,8 @@ Endpoints
 
       {
         "start": "2025-08-15T10:00:00Z",
-        "end": "2025-08-15T22:00:00Z"
+        "end": "2025-08-15T22:00:00Z",
+        "location": null
       }
 
    **Example response**:
@@ -139,7 +145,8 @@ Endpoints
       {
         "id": 17,
         "start": "2025-08-15T10:00:00Z",
-        "end": "2025-08-15T22:00:00Z"
+        "end": "2025-08-15T22:00:00Z",
+        "location": null
       }
 
    :param organizer: The ``slug`` field of the organizer of the event/item to create a program time for

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__ = "2026.4.0"
+__version__ = "2026.5.0.dev0"

src/pretix/api/serializers/fields.py

@@ -115,10 +115,10 @@ class PluginsField(serializers.Field):
 
     def to_representation(self, obj):
         from pretix.base.plugins import get_all_plugins
-
+        active_plugins = set(obj.get_plugins())
         return sorted([
             p.module for p in get_all_plugins()
-            if not p.name.startswith('.') and getattr(p, 'visible', True) and p.module in obj.get_plugins()
+            if not p.name.startswith('.') and getattr(p, 'visible', True) and p.module in active_plugins
         ])
 
     def to_internal_value(self, data):

src/pretix/api/serializers/item.py

@@ -191,7 +191,7 @@ class InlineItemAddOnSerializer(serializers.ModelSerializer):
 class InlineItemProgramTimeSerializer(serializers.ModelSerializer):
     class Meta:
         model = ItemProgramTime
-        fields = ('start', 'end')
+        fields = ('start', 'end', 'location')
 
 
 class ItemBundleSerializer(serializers.ModelSerializer):
@@ -222,7 +222,7 @@ class ItemBundleSerializer(serializers.ModelSerializer):
 class ItemProgramTimeSerializer(serializers.ModelSerializer):
     class Meta:
         model = ItemProgramTime
-        fields = ('id', 'start', 'end')
+        fields = ('id', 'start', 'end', 'location')
 
     def validate(self, data):
         data = super().validate(data)

src/pretix/api/serializers/order.py

@@ -1416,6 +1416,7 @@ class OrderCreateSerializer(I18nAwareModelSerializer):
         qa = QuotaAvailability()
         qa.queue(*[q for q, d in quota_diff_for_locking.items() if d > 0])
         qa.compute()
+        v_avail = {}
 
         # These are not technically correct as diff use due to the time offset applied above, so let's prevent accidental
         # use further down
@@ -1445,11 +1446,13 @@ class OrderCreateSerializer(I18nAwareModelSerializer):
 
                 voucher_usage[v] += 1
                 if voucher_usage[v] > 0:
-                    redeemed_in_carts = CartPosition.objects.filter(
-                        Q(voucher=pos_data['voucher']) & Q(event=self.context['event']) & Q(expires__gte=now_dt)
-                    ).exclude(pk__in=[cp.pk for cp in delete_cps])
-                    v_avail = v.max_usages - v.redeemed - redeemed_in_carts.count()
-                    if v_avail < voucher_usage[v]:
+                    if v not in v_avail:
+                        v.refresh_from_db(fields=['redeemed'])
+                        redeemed_in_carts = CartPosition.objects.filter(
+                            Q(voucher=v) & Q(event=self.context['event']) & Q(expires__gte=now_dt)
+                        ).exclude(pk__in=[cp.pk for cp in delete_cps])
+                        v_avail[v] = v.max_usages - v.redeemed - redeemed_in_carts.count()
+                    if v_avail[v] < voucher_usage[v]:
                         errs[i]['voucher'] = [
                             'The voucher has already been used the maximum number of times.'
                         ]

src/pretix/base/migrations/0299_itemprogramtime_location.py

@@ -0,0 +1,19 @@
+# Generated by Django 4.2.27 on 2026-01-21 12:06
+
+import i18nfield.fields
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("pretixbase", "0298_pluggable_permissions"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="itemprogramtime",
+            name="location",
+            field=i18nfield.fields.I18nTextField(max_length=200, null=True),
+        )
+    ]

src/pretix/base/models/items.py

@@ -2306,10 +2306,17 @@ class ItemProgramTime(models.Model):
     :type start: datetime
     :param end: The date and time this program time ends
     :type end: datetime
+    :param location: venue
+    :type location: str
     """
     item = models.ForeignKey('Item', related_name='program_times', on_delete=models.CASCADE)
     start = models.DateTimeField(verbose_name=_("Start"))
     end = models.DateTimeField(verbose_name=_("End"))
+    location = I18nTextField(
+        null=True, blank=True,
+        max_length=200,
+        verbose_name=_("Location"),
+    )
 
     def clean(self):
         if hasattr(self, 'item') and self.item and self.item.event.has_subevents:

src/pretix/base/pdf.py

@@ -498,9 +498,9 @@ DEFAULT_VARIABLES = OrderedDict((
         ) if op.valid_until else ""
     }),
     ("program_times", {
-        "label": _("Program times: date and time"),
+        "label": _("Program times"),
         "editor_sample": _(
-            "2017-05-31 10:00 – 12:00\n2017-05-31 14:00 – 16:00\n2017-05-31 14:00 – 2017-06-01 14:00"),
+            "2017-05-31 10:00 – 12:00, Room 1\n2017-05-31 14:00 – 16:00, Room 2\n2017-05-31 14:00 – 2017-06-01 14:00, Building A"),
         "evaluate": lambda op, order, ev: get_program_times(op, ev)
     }),
     ("medium_identifier", {
@@ -748,13 +748,19 @@ def get_seat(op: OrderPosition):
 
 
 def get_program_times(op: OrderPosition, ev: Event):
-    return '\n'.join([
-        datetimerange(
-            pt.start.astimezone(ev.timezone),
-            pt.end.astimezone(ev.timezone),
-            as_html=False
-        ) for pt in op.item.program_times.all()
-    ])
+    ptstr = []
+    for pt in op.item.program_times.all():
+        ptstr.append([
+            datetimerange(
+                pt.start.astimezone(ev.timezone),
+                pt.end.astimezone(ev.timezone),
+                as_html=False
+            ),
+            (', ' + ', '.join(
+                l.strip() for l in str(pt.location).splitlines() if l.strip())
+             ) if str(pt.location).strip() else ''
+        ])
+    return '\n'.join(''.join(l) for l in ptstr)
 
 
 def generate_compressed_addon_list(op, order, event, only_checked_in=False):

src/pretix/base/plugins.py

@@ -49,14 +49,39 @@ class PluginType(Enum):
     EXPORT = 4
 
 
+def plugin_is_available(meta, event=None, organizer=None):
+    if not hasattr(meta.app, 'is_available'):
+        return True
+
+    level = getattr(meta, "level", PLUGIN_LEVEL_EVENT)
+    if level == PLUGIN_LEVEL_EVENT:
+        if event:
+            return meta.app.is_available(event)
+        elif organizer:
+            if not hasattr(organizer, '_plugin_availability_fallback_event'):
+                with scope(organizer=organizer):
+                    setattr(organizer, '_plugin_availability_fallback_event', organizer.events.first())
+            return (
+                organizer._plugin_availability_fallback_event
+                and meta.app.is_available(organizer._plugin_availability_fallback_event)
+            )
+    elif level == PLUGIN_LEVEL_ORGANIZER:
+        if organizer:
+            return meta.app.is_available(organizer)
+        elif event:
+            return meta.app.is_available(event.organizer)
+    elif level == PLUGIN_LEVEL_EVENT_ORGANIZER_HYBRID and (event or organizer):
+        return meta.app.is_available(event or organizer)
+
+    return True
+
+
 def get_all_plugins(*, event=None, organizer=None) -> List[type]:
     """
     Returns the PretixPluginMeta classes of all plugins found in the installed Django apps.
     """
     assert not event or not organizer
     plugins = []
-    event_fallback = None
-    event_fallback_used = False
     for app in apps.get_app_configs():
         if hasattr(app, 'PretixPluginMeta'):
             meta = app.PretixPluginMeta
@@ -65,28 +90,8 @@ def get_all_plugins(*, event=None, organizer=None) -> List[type]:
             if app.name in settings.PRETIX_PLUGINS_EXCLUDE:
                 continue
 
-            level = getattr(meta, "level", PLUGIN_LEVEL_EVENT)
-            if level == PLUGIN_LEVEL_EVENT:
-                if event and hasattr(app, 'is_available'):
-                    if not app.is_available(event):
-                        continue
-                elif organizer and hasattr(app, 'is_available'):
-                    if not event_fallback_used:
-                        with scope(organizer=organizer):
-                            event_fallback = organizer.events.first()
-                        event_fallback_used = True
-                    if not event_fallback or not app.is_available(event_fallback):
-                        continue
-            elif level == PLUGIN_LEVEL_ORGANIZER:
-                if organizer and hasattr(app, 'is_available'):
-                    if not app.is_available(organizer):
-                        continue
-                elif event and hasattr(app, 'is_available'):
-                    if not app.is_available(event.organizer):
-                        continue
-            elif level == PLUGIN_LEVEL_EVENT_ORGANIZER_HYBRID and (event or organizer) and hasattr(app, 'is_available'):
-                if not app.is_available(event or organizer):
-                    continue
+            if not plugin_is_available(meta, event, organizer):
+                continue
 
             plugins.append(meta)
     return sorted(

src/pretix/base/reldate.py

@@ -21,7 +21,7 @@
 #
 import datetime
 from collections import namedtuple
-from typing import Union
+from typing import Tuple, Union
 from zoneinfo import ZoneInfo
 
 from dateutil import parser
@@ -34,7 +34,7 @@ from django.utils.timezone import now
 from django.utils.translation import gettext_lazy as _
 from rest_framework import serializers
 
-BASE_CHOICES = (
+EVENT_CHOICES = (
     ('date_from', _('Event start')),
     ('date_to', _('Event end')),
     ('date_admission', _('Event admission')),
@@ -42,6 +42,12 @@ BASE_CHOICES = (
     ('presale_end', _('Presale end')),
 )
 
+# extend NO_BEFORE_VALUES in reldate.js if changed
+ORDER_CHOICES = (
+    ('datetime', _('Order creation')),
+)
+ORDER_CHOICES_KEYS = {choice[0] for choice in ORDER_CHOICES}
+
 RelativeDate = namedtuple('RelativeDate', ['days', 'minutes', 'time', 'is_after', 'base_date_name'], defaults=(0, None, None, False, 'date_from'))
 
 
@@ -51,17 +57,43 @@ class RelativeDateWrapper:
     that the underlying data is either a fixed date or a number of days and a wall clock
     time to calculate the date based on a base point.
 
-    The base point can be the date_from, date_to, date_admission, presale_start or presale_end
-    attribute of an event or subevent. If the respective attribute is not set, ``date_from``
-    will be used.
+    The base point can be the ``date_from``, ``date_to``, ``date_admission``, ``presale_start``
+    or ``presale_end`` attribute of an event or subevent, as well as a ``datetime`` of an order.
+    If the respective attribute is not set, ``date_from`` will be used.
     """
 
     def __init__(self, data: Union[datetime.datetime, RelativeDate]):
         self.data = data
 
-    def date(self, event) -> datetime.date:
-        from .models import SubEvent
+    def _resolve_base_date(self, reference) -> Tuple[datetime.datetime, ZoneInfo]:
+        """
 
+        :param reference:
+        :return:
+        """
+        from .models import Event, Order, SubEvent
+
+        if self.data.base_date_name in ORDER_CHOICES_KEYS:
+            if not isinstance(reference, Order):
+                raise ValueError('A order-based relative datetime choice must be used with an order object')
+            event = reference.event
+            base_date = getattr(reference, self.data.base_date_name)
+        elif isinstance(reference, SubEvent):
+            event = reference.event
+            base_date = (getattr(reference, self.data.base_date_name) or
+                         getattr(reference.event, self.data.base_date_name) or
+                         reference.date_from)
+        elif isinstance(reference, Event):
+            event = reference
+            base_date = getattr(reference, self.data.base_date_name) or event.date_from
+        else:
+            raise TypeError("Only event, subevent or order objects are supported")
+
+        tz = ZoneInfo(event.settings.timezone)
+
+        return base_date, tz
+
+    def date(self, reference) -> datetime.date:
         if isinstance(self.data, datetime.datetime):
             return self.data.date()
         elif isinstance(self.data, datetime.date):
@@ -70,15 +102,7 @@ class RelativeDateWrapper:
             if self.data.minutes is not None:
                 raise ValueError('A minute-based relative datetime can not be used as a date')
 
-            tz = ZoneInfo(event.settings.timezone)
-            if isinstance(event, SubEvent):
-                base_date = (
-                    getattr(event, self.data.base_date_name)
-                    or getattr(event.event, self.data.base_date_name)
-                    or event.date_from
-                )
-            else:
-                base_date = getattr(event, self.data.base_date_name) or event.date_from
+            base_date, tz = self._resolve_base_date(reference)
 
             if self.data.is_after:
                 new_date = base_date.astimezone(tz) + datetime.timedelta(days=self.data.days)
@@ -86,21 +110,11 @@ class RelativeDateWrapper:
                 new_date = base_date.astimezone(tz) - datetime.timedelta(days=self.data.days)
             return new_date.date()
 
-    def datetime(self, event) -> datetime.datetime:
-        from .models import SubEvent
-
+    def datetime(self, reference) -> datetime.datetime:
         if isinstance(self.data, (datetime.datetime, datetime.date)):
             return self.data
         else:
-            tz = ZoneInfo(event.settings.timezone)
-            if isinstance(event, SubEvent):
-                base_date = (
-                    getattr(event, self.data.base_date_name)
-                    or getattr(event.event, self.data.base_date_name)
-                    or event.date_from
-                )
-            else:
-                base_date = getattr(event, self.data.base_date_name) or event.date_from
+            base_date, tz = self._resolve_base_date(reference)
 
             if self.data.minutes is not None:
                 if self.data.is_after:
@@ -172,7 +186,9 @@ class RelativeDateWrapper:
                         minutes=None,
                         is_after=len(parts) > 4 and parts[4] == "after",
                     )
-            if data.base_date_name not in [k[0] for k in BASE_CHOICES]:
+            if data.base_date_name in ORDER_CHOICES_KEYS and parts[4] != "after":
+                raise ValueError('ORDER_CHOICE: {} cannot be combined with "before"'.format(data.base_date_name))
+            if data.base_date_name not in [k[0] for k in EVENT_CHOICES + ORDER_CHOICES]:
                 raise ValueError('{} is not a valid base date'.format(data.base_date_name))
         else:
             data = parser.parse(input)
@@ -311,11 +327,17 @@ class RelativeDateTimeField(forms.MultiValueField):
         ]
         if kwargs.get('limit_choices'):
             limit = kwargs.pop('limit_choices')
-            choices = [(k, v) for k, v in BASE_CHOICES if k in limit]
+            choices = [(k, v) for k, v in EVENT_CHOICES if k in limit]
         else:
-            choices = BASE_CHOICES
+            choices = EVENT_CHOICES
+
+        self.relative_to_order = kwargs.pop('relative_to_order', False)
+        if self.relative_to_order:
+            choices += ORDER_CHOICES
+
         if not kwargs.get('required', True):
             status_choices.insert(0, ('unset', _('Not set')))
+
         fields = reldatetimeparts(
             status=forms.ChoiceField(
                 choices=status_choices,
@@ -359,12 +381,13 @@ class RelativeDateTimeField(forms.MultiValueField):
         )
 
     def set_event(self, event):
-        self.widget.widgets[reldatetimeparts.indizes.rel_days_relationto].choices = [
-            (k, v) for k, v in BASE_CHOICES if getattr(event, k, None)
-        ]
-        self.widget.widgets[reldatetimeparts.indizes.rel_mins_relationto].choices = [
-            (k, v) for k, v in BASE_CHOICES if getattr(event, k, None)
+        choices = [
+            (k, v) for k, v in EVENT_CHOICES if getattr(event, k, None)
         ]
+        if self.relative_to_order:
+            choices += ORDER_CHOICES
+        self.widget.widgets[reldateparts.indizes.rel_days_relationto].choices = choices
+        self.widget.widgets[reldatetimeparts.indizes.rel_mins_relationto].choices = choices
 
     def compress(self, data_list):
         if not data_list:
@@ -404,6 +427,10 @@ class RelativeDateTimeField(forms.MultiValueField):
             raise ValidationError(self.error_messages['incomplete'])
         elif data.status == 'relative_minutes' and (data.rel_mins_number is None or not data.rel_mins_relationto):
             raise ValidationError(self.error_messages['incomplete'])
+        elif data.status == 'relative' and data.rel_days_relationto in ORDER_CHOICES_KEYS and data.rel_days_relation == 'before':
+            raise ValidationError(_('A relative date in relation to an order can only be after the order has been placed'))
+        elif data.status == 'relative' and data.rel_mins_relationto in ORDER_CHOICES_KEYS and data.rel_mins_relation == 'before':
+            raise ValidationError(_('A relative date in relation to an order can only be after the order has been placed'))
 
         return super().clean(value)
 
@@ -424,13 +451,14 @@ class RelativeDateWidget(RelativeDateTimeWidget):
 
     def __init__(self, *args, **kwargs):
         self.status_choices = kwargs.pop('status_choices')
+        base_choices = kwargs.pop('base_choices')
         widgets = reldateparts(
             status=forms.RadioSelect(choices=self.status_choices),
             absolute=forms.DateInput(
                 attrs={'class': 'datepickerfield'}
             ),
             rel_days_number=forms.NumberInput(),
-            rel_days_relationto=forms.Select(choices=kwargs.pop('base_choices')),
+            rel_days_relationto=forms.Select(choices=base_choices),
             rel_days_relation=forms.Select(choices=BEFORE_AFTER_CHOICE),
         )
         forms.MultiWidget.__init__(self, widgets=widgets, *args, **kwargs)
@@ -474,6 +502,12 @@ class RelativeDateField(RelativeDateTimeField):
         ]
         if not kwargs.get('required', True):
             status_choices.insert(0, ('unset', _('Not set')))
+
+        choices = EVENT_CHOICES
+        self.relative_to_order = kwargs.pop('relative_to_order', False)
+        if self.relative_to_order:
+            choices += ORDER_CHOICES
+
         fields = reldateparts(
             status=forms.ChoiceField(
                 choices=status_choices,
@@ -486,7 +520,7 @@ class RelativeDateField(RelativeDateTimeField):
                 required=False
             ),
             rel_days_relationto=forms.ChoiceField(
-                choices=BASE_CHOICES,
+                choices=choices,
                 required=False
             ),
             rel_days_relation=forms.ChoiceField(
@@ -495,15 +529,18 @@ class RelativeDateField(RelativeDateTimeField):
             ),
         )
         if 'widget' not in kwargs:
-            kwargs['widget'] = RelativeDateWidget(status_choices=status_choices, base_choices=BASE_CHOICES)
+            kwargs['widget'] = RelativeDateWidget(status_choices=status_choices, base_choices=choices)
         forms.MultiValueField.__init__(
             self, fields=fields, require_all_fields=False, *args, **kwargs
         )
 
     def set_event(self, event):
-        self.widget.widgets[reldateparts.indizes.rel_days_relationto].choices = [
-            (k, v) for k, v in BASE_CHOICES if getattr(event, k, None)
+        choices = [
+            (k, v) for k, v in EVENT_CHOICES if getattr(event, k, None)
         ]
+        if self.relative_to_order:
+            choices += ORDER_CHOICES
+        self.widget.widgets[reldateparts.indizes.rel_days_relationto].choices = choices
 
     def compress(self, data_list):
         if not data_list:
@@ -527,6 +564,8 @@ class RelativeDateField(RelativeDateTimeField):
             raise ValidationError(self.error_messages['incomplete'])
         elif data.status == 'relative' and (data.rel_days_number is None or not data.rel_days_relationto):
             raise ValidationError(self.error_messages['incomplete'])
+        elif data.status == 'relative' and data.rel_days_relationto in ORDER_CHOICES_KEYS and data.rel_days_relation == 'before':
+            raise ValidationError(_('A relative date in relation to an order can only be after the order has been placed'))
 
         return forms.MultiValueField.clean(self, value)
 

src/pretix/base/services/orders.py

@@ -727,8 +727,6 @@ def _check_positions(event: Event, now_dt: datetime, time_machine_now_dt: dateti
     _check_date(event, time_machine_now_dt)
 
     products_seen = Counter()
-    q_avail = Counter()
-    v_avail = Counter()
     v_usages = Counter()
     v_budget = {}
     deleted_positions = set()
@@ -793,6 +791,9 @@ def _check_positions(event: Event, now_dt: datetime, time_machine_now_dt: dateti
                 shared_lock_objects=[event]
             )
 
+    q_avail = Counter()
+    v_avail = Counter()
+
     # Check maximum order size
     limit = min(int(event.settings.max_items_per_order), settings.PRETIX_MAX_ORDER_SIZE)
     if sum(1 for cp in sorted_positions if not cp.addon_to) > limit:

src/pretix/base/templates/pretixbase/forms/widgets/reldate.html

@@ -1,4 +1,6 @@
 {% load i18n %}
+{% load static %}
+<script src="{% static 'pretixbase/js/reldate.js' %}" defer></script>
 <div class="reldatetime">
     {% for group_name, group_choices, group-index in widget.subwidgets.0.optgroups %}
         {% for selopt in group_choices %}

src/pretix/base/templates/pretixbase/forms/widgets/reldatetime.html

@@ -1,4 +1,6 @@
 {% load i18n %}
+{% load static %}
+<script src="{% static 'pretixbase/js/reldate.js' %}" defer></script>
 <div class="reldatetime">
     {% for group_name, group_choices, group-index in widget.subwidgets.0.optgroups %}
         {% for selopt in group_choices %}

src/pretix/control/forms/item.py

@@ -574,7 +574,7 @@ class ItemCreateForm(I18nModelForm):
                 instance.bundles.create(bundled_item=b.bundled_item, bundled_variation=b.bundled_variation,
                                         count=b.count, designated_price=b.designated_price)
             for pt in self.cleaned_data['copy_from'].program_times.all():
-                instance.program_times.create(start=pt.start, end=pt.end)
+                instance.program_times.create(start=pt.start, end=pt.end, location=pt.location)
 
             item_copy_data.send(sender=self.event, source=self.cleaned_data['copy_from'], target=instance)
 
@@ -1354,6 +1354,10 @@ class ItemProgramTimeForm(I18nModelForm):
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         self.fields['end'].widget.attrs['data-date-after'] = '#id_{prefix}-start_0'.format(prefix=self.prefix)
+        self.fields['location'].widget.attrs['rows'] = '3'
+        self.fields['location'].widget.attrs['placeholder'] = _(
+            'Sample Conference Center, Heidelberg, Germany'
+        )
 
     class Meta:
         model = ItemProgramTime
@@ -1361,6 +1365,7 @@ class ItemProgramTimeForm(I18nModelForm):
         fields = [
             'start',
             'end',
+            'location'
         ]
         field_classes = {
             'start': forms.SplitDateTimeField,

src/pretix/control/templates/pretixcontrol/item/include_program_times.html

@@ -34,6 +34,7 @@
                     {% bootstrap_form_errors form %}
                     {% bootstrap_field form.start layout="control" %}
                     {% bootstrap_field form.end layout="control" %}
+                    {% bootstrap_field form.location layout="control" %}
                 </div>
             </div>
         {% endfor %}
@@ -59,6 +60,7 @@
                 <div class="panel-body form-horizontal">
                     {% bootstrap_field formset.empty_form.start layout="control" %}
                     {% bootstrap_field formset.empty_form.end layout="control" %}
+                    {% bootstrap_field formset.empty_form.location layout="control" %}
                 </div>
             </div>
         {% endescapescript %}

src/pretix/control/views/organizer.py

@@ -102,7 +102,7 @@ from pretix.base.models.organizer import (
 from pretix.base.payment import PaymentException
 from pretix.base.plugins import (
     PLUGIN_LEVEL_EVENT, PLUGIN_LEVEL_EVENT_ORGANIZER_HYBRID,
-    PLUGIN_LEVEL_ORGANIZER,
+    PLUGIN_LEVEL_ORGANIZER, plugin_is_available,
 )
 from pretix.base.services.export import (
     init_organizer_exporters, multiexport, scheduled_organizer_export,
@@ -597,6 +597,13 @@ class OrganizerCreate(CreateView):
         })
 
 
+def available_plugins(organizer):
+    from pretix.base.plugins import get_all_plugins
+
+    return (p for p in get_all_plugins(organizer=organizer) if not p.name.startswith('.')
+            and getattr(p, 'visible', True))
+
+
 class OrganizerPlugins(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixin, TemplateView, SingleObjectMixin):
     model = Organizer
     context_object_name = 'organizer'
@@ -606,12 +613,6 @@ class OrganizerPlugins(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixi
     def get_object(self, queryset=None) -> Organizer:
         return self.request.organizer
 
-    def available_plugins(self, organizer):
-        from pretix.base.plugins import get_all_plugins
-
-        return (p for p in get_all_plugins(organizer=organizer) if not p.name.startswith('.')
-                and getattr(p, 'visible', True))
-
     def prepare_links(self, pluginmeta, key):
         links = getattr(pluginmeta, key, [])
         try:
@@ -637,7 +638,7 @@ class OrganizerPlugins(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixi
         from pretix.base.plugins import CATEGORY_LABELS, CATEGORY_ORDER
 
         context = super().get_context_data(*args, **kwargs)
-        plugins = list(self.available_plugins(self.object))
+        plugins = list(available_plugins(self.object))
 
         active_counter = Counter()
         events_total = 0
@@ -685,7 +686,7 @@ class OrganizerPlugins(OrganizerDetailViewMixin, OrganizerPermissionRequiredMixi
         self.object = self.get_object()
 
         plugins_available = {
-            p.module: p for p in self.available_plugins(self.object)
+            p.module: p for p in available_plugins(self.object)
         }
         choose_events_next = False
         with transaction.atomic():
@@ -786,12 +787,6 @@ class OrganizerPluginEvents(OrganizerDetailViewMixin, OrganizerPermissionRequire
         }
         return kwargs
 
-    def available_plugins(self, organizer):
-        from pretix.base.plugins import get_all_plugins
-
-        return (p for p in get_all_plugins(organizer=organizer) if not p.name.startswith('.')
-                and getattr(p, 'visible', True))
-
     def get_context_data(self, **kwargs):
         return super().get_context_data(
             plugin=self.plugin,
@@ -799,12 +794,10 @@ class OrganizerPluginEvents(OrganizerDetailViewMixin, OrganizerPermissionRequire
         )
 
     def dispatch(self, request, *args, **kwargs):
-        plugins_available = {
-            p.module: p for p in self.available_plugins(self.request.organizer)
-        }
-        if kwargs["plugin"] not in plugins_available:
+        try:
+            self.plugin = next(p for p in available_plugins(self.request.organizer) if p.module == kwargs["plugin"])
+        except StopIteration:
             raise Http404(_("Unknown plugin."))
-        self.plugin = plugins_available[kwargs["plugin"]]
         level = getattr(self.plugin, "level", PLUGIN_LEVEL_EVENT)
         if level == PLUGIN_LEVEL_ORGANIZER:
             raise Http404(_("This plugin can only be enabled for the entire organizer account."))
@@ -835,6 +828,9 @@ class OrganizerPluginEvents(OrganizerDetailViewMixin, OrganizerPermissionRequire
         logentries_to_save = []
 
         for e in self.request.organizer.events.filter(pk__in=events_to_enable):
+            if not plugin_is_available(self.plugin, organizer=self.request.organizer, event=e):
+                messages.warning(self.request, _("This plugin cannot be activated for event {}.").format(e.name))
+                continue
             logentries_to_save.append(
                 e.log_action('pretix.event.plugins.enabled', user=self.request.user, data={'plugin': self.plugin.module}, save=False)
             )

src/pretix/plugins/badges/exporters.py

@@ -57,7 +57,7 @@ from django.utils.translation import gettext as _, gettext_lazy, pgettext_lazy
 from pypdf import PageObject, PdfReader, PdfWriter, Transformation
 from pypdf.generic import RectangleObject
 from reportlab.lib import pagesizes
-from reportlab.lib.units import mm
+from reportlab.lib.units import inch, mm
 from reportlab.pdfgen import canvas
 
 from pretix.base.exporter import BaseExporter
@@ -133,6 +133,14 @@ OPTIONS = OrderedDict([
         'offsets': [66.1 * mm, 29.6 * mm],
         'pagesize': pagesizes.A4,
     }),
+    ('avery_4inx3in', {
+        'name': 'Avery 4" x 3" (74459)',
+        'cols': 2,
+        'rows': 3,
+        'margins': [1 * inch, .25 * inch, 1 * inch, .25 * inch],
+        'offsets': [4 * inch, 3 * inch],
+        'pagesize': pagesizes.LETTER,
+    }),
     ('avery_80x50', {
         'name': 'Avery Zweckform 80 x 50 mm (L4785)',
         'cols': 2,

src/pretix/plugins/badges/templates.py

@@ -22,7 +22,7 @@
 from django.utils.text import format_lazy
 from django.utils.translation import gettext_lazy as _
 from reportlab.lib import pagesizes
-from reportlab.lib.units import mm
+from reportlab.lib.units import inch, mm
 
 
 def _simple_template(w, h):
@@ -261,4 +261,9 @@ TEMPLATES = {
         "pagesize": (88.9 * mm, 33.87 * mm),
         "layout": _simple_template(88.9 * mm, 33.87 * mm),
     },
+    "4inx3in": {
+        "label": format_lazy(_("{width} x {height} inch label"), width=4, height=3),
+        "pagesize": (4 * inch, 3 * inch),
+        "layout": _simple_template(4 * inch, 3 * inch),
+    },
 }

src/pretix/presale/ical.py

@@ -153,7 +153,7 @@ def get_private_icals(event, positions):
                     # Actual ical organizer field is not useful since it will cause "your invitation was accepted" emails to the organizer
                     descr.append(_('Organizer: {organizer}').format(organizer=event.organizer.name))
                     description = '\n'.join(descr)
-                location = None
+                location = ", ".join(l.strip() for l in str(pt.location).splitlines() if l.strip())
                 dtstart = pt.start.astimezone(tz)
                 dtend = pt.end.astimezone(tz)
                 uid = 'pretix-{}-{}-{}-{}@{}'.format(

src/pretix/settings.py

@@ -265,7 +265,7 @@ EMAIL_USE_TLS = config.getboolean('mail', 'tls', fallback=False)
 EMAIL_USE_SSL = config.getboolean('mail', 'ssl', fallback=False)
 EMAIL_SUBJECT_PREFIX = '[pretix] '
 EMAIL_BACKEND = 'django.core.mail.backends.smtp.EmailBackend'
-EMAIL_CUSTOM_SMTP_BACKEND = 'pretixbase.email.CheckPrivateNetworkSmtpBackend'
+EMAIL_CUSTOM_SMTP_BACKEND = 'pretix.base.email.CheckPrivateNetworkSmtpBackend'
 EMAIL_TIMEOUT = 60
 
 ADMINS = [('Admin', n) for n in config.get('mail', 'admins', fallback='').split(",") if n]

src/pretix/static/pretixbase/js/reldate.js

@@ -0,0 +1,44 @@
+if (!window.__reldateInitialized) {
+    window.__reldateInitialized = true;
+    document.addEventListener('DOMContentLoaded', () => {
+         const NO_BEFORE_VALUES = ['datetime'];
+
+        document.querySelectorAll('.reldatetime, .reldate').forEach(container => {
+            const groups = container.querySelectorAll('.radio');
+
+            groups.forEach(group => {
+                const selects = group.querySelectorAll('select');
+                if (selects.length < 2) return;
+
+                let referenceSelect = null;
+                let beforeAfterSelect = null;
+
+                selects.forEach(sel => {
+                    const values = Array.from(sel.options).map(o => o.value);
+                    // only attach to selects that contain problematic values
+                    if (NO_BEFORE_VALUES.some(v => values.includes(v))) {
+                        referenceSelect = sel;
+                    } else if (values.includes('before') && values.includes('after')) {
+                        beforeAfterSelect = sel;
+                    }
+                });
+                if (!referenceSelect || !beforeAfterSelect) return;
+
+                const beforeOption = beforeAfterSelect.querySelector('option[value="before"]');
+                const updateBeforeOption = () => {
+                    if (NO_BEFORE_VALUES.includes(referenceSelect.value)) {
+                        beforeOption.disabled = true;
+                        if (beforeAfterSelect.value === 'before') {
+                            beforeAfterSelect.value = 'after';
+                            beforeAfterSelect.dispatchEvent(new Event('change', { bubbles: true }));
+                        }
+                    } else {
+                        beforeOption.disabled = false;
+                    }
+                };
+                referenceSelect.addEventListener('change', updateBeforeOption);
+                updateBeforeOption();
+            });
+        });
+    });
+}

src/tests/api/test_items.py

@@ -530,6 +530,7 @@ def test_item_detail_program_times(token_client, organizer, event, team, item, c
     res["program_times"] = [{
         "start": "2017-12-27T00:00:00Z",
         "end": "2017-12-28T00:00:00Z",
+        "location": None
     }]
     resp = token_client.get('/api/v1/organizers/{}/events/{}/items/{}/'.format(organizer.slug, event.slug,
                                                                                item.pk))
@@ -1972,32 +1973,54 @@ def program_time2(item, category):
                                      end=datetime(2017, 12, 30, 0, 0, 0, tzinfo=timezone.utc))
 
 
+@pytest.fixture
+def program_time3(item, category):
+    return item.program_times.create(start=datetime(2017, 12, 30, 0, 0, 0, tzinfo=timezone.utc),
+                                     end=datetime(2017, 12, 31, 0, 0, 0, tzinfo=timezone.utc),
+                                     location='Testlocation')
+
+
 TEST_PROGRAM_TIMES_RES = {
     0: {
         "start": "2017-12-27T00:00:00Z",
         "end": "2017-12-28T00:00:00Z",
+        "location": None,
     },
     1: {
         "start": "2017-12-29T00:00:00Z",
         "end": "2017-12-30T00:00:00Z",
+        "location": None,
+    },
+    2: {
+        "start": "2017-12-30T00:00:00Z",
+        "end": "2017-12-31T00:00:00Z",
+        "location": {"en": "Testlocation"},
     }
 }
 
 
 @pytest.mark.django_db
-def test_program_times_list(token_client, organizer, event, item, program_time, program_time2):
+def test_program_times_list(token_client, organizer, event, item, program_time, program_time2, program_time3):
     res = dict(TEST_PROGRAM_TIMES_RES)
     res[0]["id"] = program_time.pk
     res[1]["id"] = program_time2.pk
+    res[2]["id"] = program_time3.pk
     resp = token_client.get('/api/v1/organizers/{}/events/{}/items/{}/program_times/'.format(organizer.slug, event.slug,
                                                                                              item.pk))
     assert resp.status_code == 200
     assert res[0]['start'] == resp.data['results'][0]['start']
     assert res[0]['end'] == resp.data['results'][0]['end']
     assert res[0]['id'] == resp.data['results'][0]['id']
+    assert res[0] == resp.data['results'][0]
     assert res[1]['start'] == resp.data['results'][1]['start']
     assert res[1]['end'] == resp.data['results'][1]['end']
     assert res[1]['id'] == resp.data['results'][1]['id']
+    assert res[1] == resp.data['results'][1]
+    assert res[2]['start'] == resp.data['results'][2]['start']
+    assert res[2]['end'] == resp.data['results'][2]['end']
+    assert res[2]['location'] == resp.data['results'][2]['location']
+    assert res[2]['id'] == resp.data['results'][2]['id']
+    assert res[2] == resp.data['results'][2]
 
 
 @pytest.mark.django_db
@@ -2039,6 +2062,59 @@ def test_program_times_create(token_client, organizer, event, item):
     assert resp.content.decode() == '{"non_field_errors":["The program end must not be before the program start."]}'
 
 
+@pytest.mark.django_db
+def test_program_times_create_location(token_client, organizer, event, item):
+    resp = token_client.post(
+        '/api/v1/organizers/{}/events/{}/items/{}/program_times/'.format(organizer.slug, event.slug, item.pk),
+        {
+            "start": "2017-12-27T00:00:00Z",
+            "end": "2017-12-28T00:00:00Z",
+            "location": {
+                "en": "Testlocation",
+                "de": "Testort"
+            }
+        },
+        format='json'
+    )
+    assert resp.status_code == 201
+    with scopes_disabled():
+        program_time = ItemProgramTime.objects.get(pk=resp.data['id'])
+    assert "Testlocation" == program_time.location.localize("en")
+    assert "Testort" == program_time.location.localize("de")
+
+
+@pytest.mark.django_db
+def test_program_times_create_without_location(token_client, organizer, event, item):
+    resp = token_client.post(
+        '/api/v1/organizers/{}/events/{}/items/{}/program_times/'.format(organizer.slug, event.slug, item.pk),
+        {
+            "start": "2017-12-27T00:00:00Z",
+            "end": "2017-12-28T00:00:00Z"
+        },
+        format='json'
+    )
+    assert resp.status_code == 201
+    assert resp.data['location'] is None
+    with scopes_disabled():
+        program_time = ItemProgramTime.objects.get(pk=resp.data['id'])
+    assert str(program_time.location) == ""
+
+    resp = token_client.post(
+        '/api/v1/organizers/{}/events/{}/items/{}/program_times/'.format(organizer.slug, event.slug, item.pk),
+        {
+            "start": "2017-12-27T00:00:00Z",
+            "end": "2017-12-28T00:00:00Z",
+            "location": None
+        },
+        format='json'
+    )
+    assert resp.status_code == 201
+    assert resp.data['location'] is None
+    with scopes_disabled():
+        program_time = ItemProgramTime.objects.get(pk=resp.data['id'])
+    assert str(program_time.location) == ""
+
+
 @pytest.mark.django_db
 def test_program_times_update(token_client, organizer, event, item, program_time):
     resp = token_client.patch(

src/tests/base/test_event_clone.py

@@ -82,7 +82,11 @@ def test_full_clone_same_organizer():
     assert item1.meta_data
     ItemProgramTime.objects.create(item=item1,
                                    start=datetime.datetime(2017, 12, 27, 0, 0, 0, tzinfo=datetime.timezone.utc),
-                                   end=datetime.datetime(2017, 12, 28, 0, 0, 0, tzinfo=datetime.timezone.utc))
+                                   end=datetime.datetime(2017, 12, 28, 0, 0, 0, tzinfo=datetime.timezone.utc),
+                                   location={
+                                       "en": "Testlocation",
+                                       "de": "Testort"
+                                   })
     assert item1.program_times
     item2 = event.items.create(category=category, tax_rule=tax_rule, name="T-shirt", default_price=15,
                                hidden_if_item_available=item1)
@@ -169,6 +173,7 @@ def test_full_clone_same_organizer():
     assert copied_item1.meta_data == item1.meta_data
     assert copied_item1.program_times.first().start == item1.program_times.first().start
     assert copied_item1.program_times.first().end == item1.program_times.first().end
+    assert copied_item1.program_times.first().location == item1.program_times.first().location
     assert copied_item2.variations.get().meta_data == item2v.meta_data
     assert copied_item1.hidden_if_available == copied_q2
     assert copied_item1.grant_membership_type == membership_type

src/tests/base/test_reldate.py

@@ -19,13 +19,13 @@
 # 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 datetime import datetime, time
+from datetime import datetime, time, timedelta
 from zoneinfo import ZoneInfo
 
 import pytest
 from django_scopes import scope
 
-from pretix.base.models import Event, Organizer
+from pretix.base.models import Event, Order, Organizer
 from pretix.base.reldate import RelativeDate, RelativeDateWrapper
 
 TOKYO = ZoneInfo('Asia/Tokyo')
@@ -147,3 +147,29 @@ def test_unserialize():
 
     rdw = RelativeDateWrapper.from_string('RELDATE/minutes/60/date_from/')
     assert rdw.data == RelativeDate(days=0, time=None, base_date_name='date_from', minutes=60)
+
+
+@pytest.mark.django_db
+def test_relative_to_order(event):
+    with scope(organizer=event.organizer):
+        order_moment = datetime(2020, 3, 29, 18, 0, 0, tzinfo=TOKYO)
+
+        order = Order.objects.create(
+            code='FOO', event=event, email='dummy@dummy.test',
+            status=Order.STATUS_PENDING, secret="k24fiuwvu8kxz3y1",
+            datetime=order_moment,
+            expires=order_moment + timedelta(days=10),
+            sales_channel=event.organizer.sales_channels.get(identifier="web"),
+            total=23, locale='en'
+        )
+
+        rdw = RelativeDateWrapper(RelativeDate(days=1, time=None, base_date_name='datetime', minutes=None))
+        assert rdw.datetime(order).astimezone(TOKYO) == datetime(2020, 3, 28, 18, 0, 0, tzinfo=TOKYO)
+        assert rdw.to_string() == 'RELDATE/1/-/datetime/'
+        # this is expressible as a RelativeDate but the Wrapper should catch it as invalid when parsing
+        with pytest.raises(ValueError):
+            rdw.from_string(rdw.to_string())
+
+        rdw = RelativeDateWrapper(RelativeDate(days=1, time=None, base_date_name='datetime', minutes=None, is_after=True))
+        assert rdw.datetime(order).astimezone(TOKYO) == datetime(2020, 3, 30, 18, 0, 0, tzinfo=TOKYO)
+        assert rdw.to_string() == 'RELDATE/1/-/datetime/after'

src/tests/control/test_items.py

@@ -692,7 +692,8 @@ class ItemsTest(ItemFormTest):
         self.item2.program_times.create(start=datetime.datetime(2017, 12, 27, 0, 0, 0,
                                                                 tzinfo=datetime.timezone.utc),
                                         end=datetime.datetime(2017, 12, 28, 0, 0, 0,
-                                                              tzinfo=datetime.timezone.utc))
+                                                              tzinfo=datetime.timezone.utc),
+                                        location={"en": "Testlocation", "de": "Testort"})
 
         doc = self.get_doc('/control/event/%s/%s/items/add?copy_from=%d' % (self.orga1.slug, self.event1.slug, self.item2.pk))
         data = extract_form_fields(doc.select("form")[0])
@@ -723,6 +724,7 @@ class ItemsTest(ItemFormTest):
             assert set([str(v.value) for v in i_new.variations.all()]) == set([str(v.value) for v in i_old.variations.all()])
             assert i_old.program_times.first().start == i_new.program_times.first().start
             assert i_old.program_times.first().end == i_new.program_times.first().end
+            assert i_old.program_times.first().location == i_new.program_times.first().location
 
     def test_add_to_existing_quota(self):
         with scopes_disabled():