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Configure Google Cloud Storage Bucket Notifications with Pub/Sub (gcloud CLI)🔗

1. Create a Pub/Sub Topic🔗

gcloud pubsub topics create dsx-gcs-notifications

This topic will receive events whenever objects are created in the bucket.

2. Get the Project Number🔗

gcloud projects describe PROJECT_ID --format="value(projectNumber)"
where PROJECT_ID is the name of your project.

Example output:

123456789012

Save this value — it will be used to grant permissions to the Cloud Storage service account.

3. Allow Cloud Storage to Publish to the Topic🔗

gcloud pubsub topics add-iam-policy-binding dsx-gcs-notifications \
  --member=serviceAccount:service-PROJECT_NUMBER@gs-project-accounts.iam.gserviceaccount.com \
  --role=roles/pubsub.publisher

Replace PROJECT_NUMBER with the number obtained in the previous step.

4. Create the Bucket Notification🔗

gcloud storage buckets notifications create gs://BUCKET_NAME \
  --topic=dsx-gcs-notifications \
  --event-types=OBJECT_FINALIZE \
  --payload-format=json

OBJECT_FINALIZE triggers when a file upload is completed.

5. Create a Pub/Sub Subscription🔗

gcloud pubsub subscriptions create dsx-gcs-sub \
  --topic=dsx-gcs-notifications

The subscription ID is the name used above (dsx-gcs-sub).

(Optional) Test the Notification🔗

Upload a file to the bucket, then pull messages:

gcloud pubsub subscriptions pull dsx-gcs-sub --auto-ack

You should see a JSON message containing the bucket name and object key.