Implement notifications for admin users (#700)

* First stab at notification settings

* Add "global" setting for notification levels

* Trigger notification task

* Get users with permission for event

* Actually send notification emails

* More notifications

* Allow to turn off notifications

* Link in email to pause all notifications

* Add NotificationType to wordlist

* Add notification tests

* Add documentation

* Rebase fixes

src/pretix/base/models/__init__.py

@@ -12,6 +12,7 @@ from .items import (
     Quota, SubEventItem, SubEventItemVariation, itempicture_upload_to,
 )
 from .log import LogEntry
+from .notifications import NotificationSetting
 from .orders import (
     AbstractPosition, CachedCombinedTicket, CachedTicket, CartPosition,
     InvoiceAddress, Order, OrderPosition, QuestionAnswer,

src/pretix/base/models/auth.py

@@ -7,6 +7,7 @@ from django.contrib.auth.models import (
 from django.contrib.contenttypes.models import ContentType
 from django.db import models
 from django.db.models import Q
+from django.utils.crypto import get_random_string
 from django.utils.translation import ugettext_lazy as _
 from django_otp.models import Device
 
@@ -40,6 +41,10 @@ class UserManager(BaseUserManager):
         return user
 
 
+def generate_notifications_token():
+    return get_random_string(length=32)
+
+
 class User(AbstractBaseUser, PermissionsMixin, LoggingMixin):
     """
     This is the user model used by pretix for authentication.
@@ -81,6 +86,12 @@ class User(AbstractBaseUser, PermissionsMixin, LoggingMixin):
                                 default=settings.TIME_ZONE,
                                 verbose_name=_('Timezone'))
     require_2fa = models.BooleanField(default=False)
+    notifications_send = models.BooleanField(
+        default=True,
+        verbose_name=_('Receive notifications according to my settings below'),
+        help_text=_('If turned off, you will not get any notifications.')
+    )
+    notifications_token = models.CharField(max_length=255, default=generate_notifications_token)
 
     objects = UserManager()
 

src/pretix/base/models/base.py

@@ -47,6 +47,8 @@ class LoggingMixin:
         """
         from .log import LogEntry
         from .event import Event
+        from ..notifications import get_all_notification_types
+        from ..services.notifications import notify
 
         event = None
         if isinstance(self, Event):
@@ -60,6 +62,9 @@ class LoggingMixin:
             logentry.data = json.dumps(data, cls=CustomJSONEncoder)
         logentry.save()
 
+        if action in get_all_notification_types():
+            notify.apply_async(args=(logentry.pk,))
+
 
 class LoggedModel(models.Model, LoggingMixin):
 

src/pretix/base/models/event.py

@@ -10,7 +10,7 @@ from django.core.files.storage import default_storage
 from django.core.mail import get_connection
 from django.core.validators import RegexValidator
 from django.db import models
-from django.db.models import Q
+from django.db.models import Exists, OuterRef, Q
 from django.template.defaultfilters import date as _date
 from django.utils.crypto import get_random_string
 from django.utils.functional import cached_property
@@ -26,7 +26,7 @@ from pretix.helpers.daterange import daterange
 from pretix.helpers.json import safe_string
 
 from ..settings import settings_hierarkey
-from .organizer import Organizer
+from .organizer import Organizer, Team
 
 
 class EventMixin:
@@ -511,6 +511,39 @@ class Event(EventMixin, LoggedModel):
         data.update({v.property.name: v.value for v in self.meta_values.select_related('property').all()})
         return data
 
+    def get_users_with_any_permission(self):
+        """
+        Returns a queryset of users who have any permission to this event.
+
+        :return: Iterable of User
+        """
+        return self.get_users_with_permission(None)
+
+    def get_users_with_permission(self, permission):
+        """
+        Returns a queryset of users who have a specific permission to this event.
+
+        :return: Iterable of User
+        """
+        from .auth import User
+
+        if permission:
+            kwargs = {permission: True}
+        else:
+            kwargs = {}
+
+        team_with_perm = Team.objects.filter(
+            members__pk=OuterRef('pk'),
+            organizer=self.organizer,
+            **kwargs
+        ).filter(
+            Q(all_events=True) | Q(limit_events__pk=self.pk)
+        )
+
+        return User.objects.annotate(twp=Exists(team_with_perm)).filter(
+            Q(is_superuser=True) | Q(twp=True)
+        )
+
 
 class SubEvent(EventMixin, LoggedModel):
     """
@@ -665,6 +698,21 @@ class RequiredAction(models.Model):
                 return response
         return self.action_type
 
+    def save(self, *args, **kwargs):
+        created = not self.pk
+        super().save(*args, **kwargs)
+        if created:
+            from .log import LogEntry
+            from ..services.notifications import notify
+
+            logentry = LogEntry.objects.create(
+                content_object=self,
+                action_type='pretix.event.action_required',
+                event=self.event,
+                visible=False
+            )
+            notify.apply_async(args=(logentry.pk,))
+
 
 class EventMetaProperty(LoggedModel):
     """

src/pretix/base/models/log.py

@@ -11,6 +11,11 @@ from django.utils.translation import pgettext_lazy, ugettext_lazy as _
 from pretix.base.signals import logentry_object_link
 
 
+class VisibleOnlyManager(models.Manager):
+    def get_queryset(self):
+        return super().get_queryset().filter(visible=True)
+
+
 class LogEntry(models.Model):
     """
     Represents a change or action that has been performed on another object
@@ -39,6 +44,10 @@ class LogEntry(models.Model):
     event = models.ForeignKey('Event', null=True, blank=True, on_delete=models.CASCADE)
     action_type = models.CharField(max_length=255)
     data = models.TextField(default='{}')
+    visible = models.BooleanField(default=True)
+
+    objects = VisibleOnlyManager()
+    all = models.Manager()
 
     class Meta:
         ordering = ('-datetime',)

src/pretix/base/models/notifications.py

@@ -0,0 +1,36 @@
+from django.db import models
+from django.utils.translation import ugettext_lazy as _
+
+
+class NotificationSetting(models.Model):
+    """
+    Stores that a user wants to get notifications of a certain type via a certain
+    method for a certain event. If event is None, the notification shall be sent
+    for all events the user has access to.
+
+    :param user: The user to nofify.
+    :type user: User
+    :param action_type: The type of action to notify for.
+    :type action_type: str
+    :param event: The event to notify for.
+    :type event: Event
+    :param method: The method to notify with.
+    :type method: str
+    :param enabled: Indicates whether the specified notification is enabled. If no
+                    event is set, this must always be true. If no event is set, setting
+                    this to false is equivalent to deleting the object.
+    :type enabled: bool
+    """
+    CHANNELS = (
+        ('mail', _('E-mail')),
+    )
+    user = models.ForeignKey('User', on_delete=models.CASCADE,
+                             related_name='notification_settings')
+    action_type = models.CharField(max_length=255)
+    event = models.ForeignKey('Event', null=True, blank=True, on_delete=models.CASCADE,
+                              related_name='notification_settings')
+    method = models.CharField(max_length=255, choices=CHANNELS)
+    enabled = models.BooleanField(default=True)
+
+    class Meta:
+        unique_together = ('user', 'action_type', 'event', 'method')