log when auto-assignment happens

src/sentry/models/projectownership.py

@@ -1,3 +1,4 @@
+import logging
 from typing import TYPE_CHECKING, Any, Mapping, Optional, Sequence, Tuple, Union
 
 from django.db import models
@@ -18,6 +19,8 @@
     from sentry.models import ProjectCodeOwners, Team
     from sentry.services.hybrid_cloud.user import RpcUser
 
+logger = logging.getLogger(__name__)
+
 READ_CACHE_DURATION = 3600
 
 
@@ -303,6 +306,19 @@ def handle_auto_assignment(cls, project_id, event):
                     project_id=project_id,
                     group_id=event.group.id,
                 )
+                logger.info(
+                    "handle_auto_assignment.success",
+                    extra={
+                        "event": event.event_id,
+                        "group": event.group_id,
+                        "project": event.project_id,
+                        "organization": event.project.organization_id,
+                        # owner_id returns a string including the owner type (user or team) and id
+                        "assignee": issue_owner.owner_id(),
+                        "reason": "created" if assignment["new_assignment"] else "updated",
+                        **details,
+                    },
+                )
 
     @classmethod
     def _matching_ownership_rules(