fix: notifications about packages being duplicated

Author: florentc

src/shared/channels.py

@@ -40,14 +40,24 @@ class ContainerChannel(TriggerChannel):
     lock_notifications = True
 
 
+# We have two channels for CVEDerivationClusterProposal for two usages:
+# 1. Caching suggestions: this operation is idempotent and performance sensitive so we disable locking on this channel
+# 2. Notifying subscribed users of activity on their packages: this operation is not performance sensitive and we don't want duplicate notifications so we enable locking on this channel
 @dataclass
-class CVEDerivationClusterProposalChannel(TriggerChannel):
+class CVEDerivationClusterProposalCacheChannel(TriggerChannel):
     model = CVEDerivationClusterProposal
     # We don't need to lock notifications.
     # If we are caching twice the same proposal, we will just replace it.
     lock_notifications = False
 
 
+@dataclass
+class CVEDerivationClusterProposalNotificationChannel(TriggerChannel):
+    model = CVEDerivationClusterProposal
+    # We don't want to trigger user notifications more than once
+    lock_notifications = True
+
+
 @dataclass
 class NixpkgsIssueChannel(TriggerChannel):
     model = NixpkgsIssue

src/shared/listeners/cache_suggestions.py

@@ -8,7 +8,7 @@
 import pgpubsub
 from django.db.models import Prefetch
 
-from shared.channels import CVEDerivationClusterProposalChannel
+from shared.channels import CVEDerivationClusterProposalCacheChannel
 from shared.models import NixDerivation, NixMaintainer
 from shared.models.cached import CachedSuggestions
 from shared.models.cve import AffectedProduct, Metric, Version
@@ -170,7 +170,7 @@ def cache_new_suggestions(suggestion: CVEDerivationClusterProposal) -> None:
 #         CachedSuggestions.objects.filter(pk=new.pk).delete()
 
 
-@pgpubsub.post_insert_listener(CVEDerivationClusterProposalChannel)
+@pgpubsub.post_insert_listener(CVEDerivationClusterProposalCacheChannel)
 def cache_new_suggestions_following_new_container(
     old: CVEDerivationClusterProposal, new: CVEDerivationClusterProposal
 ) -> None:

src/shared/listeners/notify_users.py

@@ -3,7 +3,7 @@
 import pgpubsub
 from django.contrib.auth.models import User
 
-from shared.channels import CVEDerivationClusterProposalChannel
+from shared.channels import CVEDerivationClusterProposalNotificationChannel
 from shared.models.linkage import CVEDerivationClusterProposal
 from webview.models import Notification
 
@@ -61,7 +61,7 @@ def create_package_subscription_notifications(
             logger.error(f"Failed to create notification for user {user.username}: {e}")
 
 
-@pgpubsub.post_insert_listener(CVEDerivationClusterProposalChannel)
+@pgpubsub.post_insert_listener(CVEDerivationClusterProposalNotificationChannel)
 def notify_subscribed_users_following_suggestion_insert(
     old: CVEDerivationClusterProposal, new: CVEDerivationClusterProposal
 ) -> None:

src/shared/migrations/0058_remove_cvederivationclusterproposal_pgpubsub_8c7ef_and_more.py

@@ -0,0 +1,27 @@
+# Generated by Django 4.2.24 on 2025-10-31 13:17
+
+from django.db import migrations
+import pgtrigger.compiler
+import pgtrigger.migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('shared', '0057_nixderivation_shared_nixd_attribu_5fcca7_btree'),
+    ]
+
+    operations = [
+        pgtrigger.migrations.RemoveTrigger(
+            model_name='cvederivationclusterproposal',
+            name='pgpubsub_8c7ef',
+        ),
+        pgtrigger.migrations.AddTrigger(
+            model_name='cvederivationclusterproposal',
+            trigger=pgtrigger.compiler.Trigger(name='pgpubsub_6aede', sql=pgtrigger.compiler.UpsertTriggerSql(declare='DECLARE payload JSONB; notification_context_text TEXT;', func='\n            \n            payload := \'{"app": "shared", "model": "CVEDerivationClusterProposal"}\'::jsonb;\n            payload := jsonb_insert(payload, \'{old}\', COALESCE(to_jsonb(OLD), \'null\'));\n            payload := jsonb_insert(payload, \'{new}\', COALESCE(to_jsonb(NEW), \'null\'));\n            SELECT current_setting(\'pgpubsub.notification_context\', True) INTO notification_context_text;\n            IF COALESCE(notification_context_text, \'\') = \'\' THEN\n                notification_context_text := \'{}\';\n            END IF;\n            payload := jsonb_insert(payload, \'{context}\', notification_context_text::jsonb);\n        \n            \n            perform pg_notify(\'pgpubsub_6aede\', payload::text);\n            RETURN NEW;\n        ', hash='3fc8ef40725c909c32771363fbb4ae378e50302c', operation='INSERT', pgid='pgtrigger_pgpubsub_6aede_fc173', table='shared_cvederivationclusterproposal', when='AFTER')),
+        ),
+        pgtrigger.migrations.AddTrigger(
+            model_name='cvederivationclusterproposal',
+            trigger=pgtrigger.compiler.Trigger(name='pgpubsub_07e32', sql=pgtrigger.compiler.UpsertTriggerSql(declare='DECLARE payload JSONB; notification_context_text TEXT;', func='\n            \n            payload := \'{"app": "shared", "model": "CVEDerivationClusterProposal"}\'::jsonb;\n            payload := jsonb_insert(payload, \'{old}\', COALESCE(to_jsonb(OLD), \'null\'));\n            payload := jsonb_insert(payload, \'{new}\', COALESCE(to_jsonb(NEW), \'null\'));\n            SELECT current_setting(\'pgpubsub.notification_context\', True) INTO notification_context_text;\n            IF COALESCE(notification_context_text, \'\') = \'\' THEN\n                notification_context_text := \'{}\';\n            END IF;\n            payload := jsonb_insert(payload, \'{context}\', notification_context_text::jsonb);\n        \n            \n            INSERT INTO pgpubsub_notification (channel, payload)\n            VALUES (\'pgpubsub_07e32\', payload);\n        \n            perform pg_notify(\'pgpubsub_07e32\', payload::text);\n            RETURN NEW;\n        ', hash='eef760200ecd9145771d2d5b5c1d9bc1f96fb2ac', operation='INSERT', pgid='pgtrigger_pgpubsub_07e32_acce7', table='shared_cvederivationclusterproposal', when='AFTER')),
+        ),
+    ]