events: allow setting a mapping for webhook transport to customise request payloads

closes #1383

Signed-off-by: Jens Langhammer <jens.langhammer@beryju.org>

authentik/events/api/notification_mapping.py

@@ -0,0 +1,28 @@
+"""NotificationWebhookMapping API Views"""
+from rest_framework.serializers import ModelSerializer
+from rest_framework.viewsets import ModelViewSet
+
+from authentik.core.api.used_by import UsedByMixin
+from authentik.events.models import NotificationWebhookMapping
+
+
+class NotificationWebhookMappingSerializer(ModelSerializer):
+    """NotificationWebhookMapping Serializer"""
+
+    class Meta:
+
+        model = NotificationWebhookMapping
+        fields = [
+            "pk",
+            "name",
+            "expression",
+        ]
+
+
+class NotificationWebhookMappingViewSet(UsedByMixin, ModelViewSet):
+    """NotificationWebhookMapping Viewset"""
+
+    queryset = NotificationWebhookMapping.objects.all()
+    serializer_class = NotificationWebhookMappingSerializer
+    filterset_fields = ["name"]
+    ordering = ["name"]

authentik/events/api/notification_transport.py

@@ -38,6 +38,7 @@ class NotificationTransportSerializer(ModelSerializer):
             "mode",
             "mode_verbose",
             "webhook_url",
+            "webhook_mapping",
             "send_once",
         ]
 

authentik/events/migrations/0018_auto_20210911_2217.py

@@ -0,0 +1,46 @@
+# Generated by Django 3.2.6 on 2021-09-11 22:17
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("authentik_core", "0028_alter_token_intent"),
+        ("authentik_events", "0017_alter_event_action"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="NotificationWebhookMapping",
+            fields=[
+                (
+                    "propertymapping_ptr",
+                    models.OneToOneField(
+                        auto_created=True,
+                        on_delete=django.db.models.deletion.CASCADE,
+                        parent_link=True,
+                        primary_key=True,
+                        serialize=False,
+                        to="authentik_core.propertymapping",
+                    ),
+                ),
+            ],
+            options={
+                "verbose_name": "Notification Webhook Mapping",
+                "verbose_name_plural": "Notification Webhook Mappings",
+            },
+            bases=("authentik_core.propertymapping",),
+        ),
+        migrations.AddField(
+            model_name="notificationtransport",
+            name="webhook_mapping",
+            field=models.ForeignKey(
+                default=None,
+                null=True,
+                on_delete=django.db.models.deletion.SET_DEFAULT,
+                to="authentik_events.notificationwebhookmapping",
+            ),
+        ),
+    ]

authentik/events/models.py

@@ -2,7 +2,7 @@
 from datetime import timedelta
 from inspect import getmodule, stack
 from smtplib import SMTPException
-from typing import Optional, Union
+from typing import TYPE_CHECKING, Optional, Type, Union
 from uuid import uuid4
 
 from django.conf import settings
@@ -15,7 +15,7 @@ from structlog.stdlib import get_logger
 
 from authentik import __version__
 from authentik.core.middleware import SESSION_IMPERSONATE_ORIGINAL_USER, SESSION_IMPERSONATE_USER
-from authentik.core.models import ExpiringModel, Group, User
+from authentik.core.models import ExpiringModel, Group, PropertyMapping, User
 from authentik.events.geo import GEOIP_READER
 from authentik.events.utils import cleanse_dict, get_user, model_to_dict, sanitize_dict
 from authentik.lib.sentry import SentryIgnoredException
@@ -27,6 +27,8 @@ from authentik.tenants.models import Tenant
 from authentik.tenants.utils import DEFAULT_TENANT
 
 LOGGER = get_logger("authentik.events")
+if TYPE_CHECKING:
+    from rest_framework.serializers import Serializer
 
 
 def default_event_duration():
@@ -220,6 +222,9 @@ class NotificationTransport(models.Model):
     mode = models.TextField(choices=TransportMode.choices)
 
     webhook_url = models.TextField(blank=True)
+    webhook_mapping = models.ForeignKey(
+        "NotificationWebhookMapping", on_delete=models.SET_DEFAULT, null=True, default=None
+    )
     send_once = models.BooleanField(
         default=False,
         help_text=_(
@@ -239,15 +244,22 @@ class NotificationTransport(models.Model):
 
     def send_webhook(self, notification: "Notification") -> list[str]:
         """Send notification to generic webhook"""
+        default_body = {
+            "body": notification.body,
+            "severity": notification.severity,
+            "user_email": notification.user.email,
+            "user_username": notification.user.username,
+        }
+        if self.webhook_mapping:
+            default_body = self.webhook_mapping.evaluate(
+                user=notification.user,
+                request=None,
+                notification=notification,
+            )
         try:
             response = get_http_session().post(
                 self.webhook_url,
-                json={
-                    "body": notification.body,
-                    "severity": notification.severity,
-                    "user_email": notification.user.email,
-                    "user_username": notification.user.username,
-                },
+                json=default_body,
             )
             response.raise_for_status()
         except RequestException as exc:
@@ -414,3 +426,25 @@ class NotificationRule(PolicyBindingModel):
 
         verbose_name = _("Notification Rule")
         verbose_name_plural = _("Notification Rules")
+
+
+class NotificationWebhookMapping(PropertyMapping):
+    """Modify the schema and layout of the webhook being sent"""
+
+    @property
+    def component(self) -> str:
+        return "ak-property-mapping-notification-form"
+
+    @property
+    def serializer(self) -> Type["Serializer"]:
+        from authentik.events.api.notification_mapping import NotificationWebhookMappingSerializer
+
+        return NotificationWebhookMappingSerializer
+
+    def __str__(self):
+        return f"Notification Webhook Mapping {self.name}"
+
+    class Meta:
+
+        verbose_name = _("Notification Webhook Mapping")
+        verbose_name_plural = _("Notification Webhook Mappings")