fix: don't process subscriptions with no assets (#17988)

ee/tasks/subscriptions/__init__.py

@@ -3,7 +3,7 @@
 
 import structlog
 from prometheus_client import Counter
-from sentry_sdk import capture_exception
+from sentry_sdk import capture_exception, capture_message
 
 from ee.tasks.subscriptions.email_subscriptions import send_email_subscription_report
 from ee.tasks.subscriptions.slack_subscriptions import send_slack_subscription_report
@@ -41,11 +41,15 @@ def _deliver_subscription_report(
             # Same value as before so nothing to do
             return
 
+    insights, assets = generate_assets(subscription)
+
+    if not assets:
+        capture_message("No assets are in this subscription", tags={"subscription_id": subscription.id})
+        return
+
     if subscription.target_type == "email":
         SUBSCRIPTION_QUEUED.labels(destination="email").inc()
 
-        insights, assets = generate_assets(subscription)
-
         # Send emails
         emails = subscription.target_value.split(",")
         if is_new_subscription_target:
@@ -77,7 +81,6 @@ def _deliver_subscription_report(
     elif subscription.target_type == "slack":
         SUBSCRIPTION_QUEUED.labels(destination="slack").inc()
 
-        insights, assets = generate_assets(subscription)
         try:
             send_slack_subscription_report(
                 subscription, assets, total_asset_count=len(insights), is_new_subscription=is_new_subscription_target

ee/tasks/subscriptions/subscription_utils.py

@@ -44,9 +44,12 @@ def generate_assets(
         ]
         ExportedAsset.objects.bulk_create(assets)
 
+        if not assets:
+            return insights, assets
+
         # Wait for all assets to be exported
         tasks = [exporter.export_asset.si(asset.id) for asset in assets]
-        # run them one after the other so we don't exhaust celery workers
+        # run them one after the other, so we don't exhaust celery workers
         parallel_job = chain(*tasks).apply_async()
 
         wait_for_parallel_celery_group(