feat(group-attributes): log a metric when certain fields for Group and related tables are updated (#52646)

We're gathering metrics when any of the following postgres DB tables are
mutated:
- Group, GroupAssignee, GroupOwner rows are created or deleted
- Group.status, Group.substatus, Group.first_seen, Group.num_comments
are updated

These metrics will help us gauge how 'active' these columns are for the
purposes of replicating these values to snuba.

Author: barkbarkimashark

src/sentry/issues/attributes.py

@@ -0,0 +1,106 @@
+import logging
+from enum import Enum
+from typing import Optional
+
+from django.db.models.signals import post_delete, post_save
+from django.dispatch import receiver
+
+from sentry.models import Group, GroupOwner
+from sentry.signals import issue_assigned, issue_deleted, issue_unassigned
+from sentry.utils import metrics
+
+logger = logging.getLogger(__name__)
+
+
+class Operation(Enum):
+    CREATED = "created"
+    UPDATED = "updated"
+    DELETED = "deleted"
+
+
+def _log_group_attributes_changed(
+    operation: Operation,
+    model_inducing_snapshot: str,
+    column_inducing_snapshot: Optional[str] = None,
+) -> None:
+    metrics.incr(
+        "group_attributes.changed",
+        tags={
+            "operation": operation.value,
+            "model": model_inducing_snapshot,
+            "column": column_inducing_snapshot,
+        },
+    )
+
+
+@receiver(
+    post_save, sender=Group, dispatch_uid="post_save_log_group_attributes_changed", weak=False
+)
+def post_save_log_group_attributes_changed(
+    instance, sender, created, update_fields, *args, **kwargs
+):
+    try:
+        if created:
+            _log_group_attributes_changed(Operation.CREATED, "group", None)
+        else:
+            # we have no guarantees update_fields is used everywhere save() is called
+            # we'll need to assume any of the attributes are updated in that case
+            attributes_updated = {"status", "substatus", "num_comments"}.intersection(
+                update_fields or ()
+            )
+            if attributes_updated:
+                _log_group_attributes_changed(
+                    Operation.UPDATED, "group", "-".join(sorted(attributes_updated))
+                )
+    except Exception:
+        logger.error("failed to log group attributes after group post_save", exc_info=True)
+
+
+@issue_deleted.connect(weak=False)
+def on_issue_deleted_log_deleted(group, user, delete_type, **kwargs):
+    try:
+        _log_group_attributes_changed(Operation.DELETED, "group", "all")
+    except Exception:
+        logger.error("failed to log group attributes after group delete", exc_info=True)
+
+
+@issue_assigned.connect(weak=False)
+def on_issue_assigned_log_group_assignee_attributes_changed(project, group, user, **kwargs):
+    try:
+        _log_group_attributes_changed(Operation.UPDATED, "group_assignee", "all")
+    except Exception:
+        logger.error(
+            "failed to log group attributes after group_assignee assignment", exc_info=True
+        )
+
+
+@issue_unassigned.connect(weak=False)
+def on_issue_unassigned_log_group_assignee_attributes_changed(project, group, user, **kwargs):
+    try:
+        _log_group_attributes_changed(Operation.DELETED, "group_assignee", "all")
+    except Exception:
+        logger.error(
+            "failed to log group attributes after group_assignee unassignment", exc_info=True
+        )
+
+
+@receiver(
+    post_save, sender=GroupOwner, dispatch_uid="post_save_log_group_owner_changed", weak=False
+)
+def post_save_log_group_owner_changed(instance, sender, created, update_fields, *args, **kwargs):
+    try:
+        _log_group_attributes_changed(
+            Operation.CREATED if created else Operation.UPDATED, "group_owner", "all"
+        )
+    except Exception:
+        logger.error("failed to log group attributes after group_owner updated", exc_info=True)
+
+
+@receiver(
+    post_delete, sender=GroupOwner, dispatch_uid="post_delete_log_group_owner_changed", weak=False
+)
+def post_delete_log_group_owner_changed(instance, sender, created, update_fields, *args, **kwargs):
+    try:
+        _log_group_attributes_changed(Operation.DELETED, "group_owner", "all")
+    except Exception:
+        logger.error("failed to log group attributes after group_owner delete", exc_info=True)

src/sentry/models/activity.py

@@ -6,6 +6,7 @@
 from django.conf import settings
 from django.db import models
 from django.db.models import F
+from django.db.models.signals import post_save
 from django.utils import timezone
 
 from sentry.db.models import (
@@ -132,14 +133,24 @@ def save(self, *args, **kwargs):
 
         # HACK: support Group.num_comments
         if self.type == ActivityType.NOTE.value:
+            from sentry.models import Group
+
             self.group.update(num_comments=F("num_comments") + 1)
+            post_save.send_robust(
+                sender=Group, instance=self.group, created=True, update_fields=["num_comments"]
+            )
 
     def delete(self, *args, **kwargs):
         super().delete(*args, **kwargs)
 
         # HACK: support Group.num_comments
         if self.type == ActivityType.NOTE.value:
+            from sentry.models import Group
+
             self.group.update(num_comments=F("num_comments") - 1)
+            post_save.send_robust(
+                sender=Group, instance=self.group, created=True, update_fields=["num_comments"]
+            )
 
     def send_notification(self):
         activity.send_activity_notifications.delay(self.id)

src/sentry/models/groupassignee.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import logging
 from typing import TYPE_CHECKING, Dict
 
 from django.conf import settings
@@ -17,14 +18,16 @@
 from sentry.models.grouphistory import GroupHistoryStatus, record_group_history
 from sentry.models.groupowner import GroupOwner
 from sentry.notifications.types import GroupSubscriptionReason
-from sentry.signals import issue_assigned
+from sentry.signals import issue_assigned, issue_unassigned
 from sentry.types.activity import ActivityType
 from sentry.utils import metrics
 
 if TYPE_CHECKING:
     from sentry.models import ActorTuple, Group, Team, User
     from sentry.services.hybrid_cloud.user import RpcUser
 
+logger = logging.getLogger(__name__)
+
 
 class GroupAssigneeManager(BaseManager):
     def assign(
@@ -134,6 +137,10 @@ def deassign(self, group: Group, acting_user: User | RpcUser | None = None) -> N
             ):
                 sync_group_assignee_outbound(group, None, assign=False)
 
+            issue_unassigned.send_robust(
+                project=group.project, group=group, user=acting_user, sender=self.__class__
+            )
+
 
 @region_silo_only_model
 class GroupAssignee(Model):

src/sentry/signals.py

@@ -159,6 +159,7 @@ def send_robust(self, sender, **named) -> List[Tuple[Receiver, Union[Exception,
 
 # issues
 issue_assigned = BetterSignal()  # ["project", "group", "user"]
+issue_unassigned = BetterSignal()  # ["project", "group", "user"]
 issue_deleted = BetterSignal()  # ["group", "user", "delete_type"]
 # ["organization_id", "project", "group", "user", "resolution_type"]
 issue_resolved = BetterSignal()

src/sentry/tasks/post_process.py

@@ -7,6 +7,7 @@
 
 import sentry_sdk
 from django.conf import settings
+from django.db.models.signals import post_save
 from django.utils import timezone
 from google.api_core.exceptions import ServiceUnavailable
 
@@ -368,6 +369,12 @@ def handle_group_owners(project, group, issue_owners):
                         )
             if new_group_owners:
                 GroupOwner.objects.bulk_create(new_group_owners)
+                for go in new_group_owners:
+                    post_save.send_robust(
+                        sender=GroupOwner,
+                        instance=go,
+                        created=True,
+                    )
 
     except UnableToAcquireLock:
         pass