Expand published notifications with data field

If the notification to be published is regarding a Role, Identity or
Consent object, we now add the 'data' field with a 'person_id' key where
the value is the id of the Person connected to the Role, Identity or
Consent.

Resolve: GREG-64

greg/management/commands/start_notification_publisher.py

@@ -2,6 +2,7 @@ import json
 import logging
 import signal
 import sys
+from typing import Union
 
 import daemon
 import lockfile
@@ -60,14 +61,17 @@ def create_cloud_event_payload(n: Notification) -> str:
     """
 
     object_type = camel_to_snake(n.object_type)
-    return json.dumps(
-        {
-            "id": str(n.id),
-            "source": f"urn:greg:{settings.INSTANCE_NAME}:{object_type}:{n.identifier}",
-            "specversion": "1.0",
-            "type": generate_event_type(n),
+    content: dict[str, Union[str, dict[str, str]]] = {
+        "id": str(n.id),
+        "source": f"urn:greg:{settings.INSTANCE_NAME}:{object_type}:{n.identifier}",
+        "specversion": "1.0",
+        "type": generate_event_type(n),
+    }
+    if n.object_type in ("Role", "Consent", "Identity"):
+        content["data"] = {
+            "person_id": n.meta.get("person_id"),
         }
-    )
+    return json.dumps(content)
 
 
 def handle_one_notification(notification: Notification, pcm: PCM, exchange: str):