Quickstart: Receiving Cloud Storage events

This page shows you how to receive events from Cloud Storage in a Cloud Run (fully managed) service using Eventarc. You can complete this quickstart using either the Google Cloud Console or the gcloud command-line tool.

In this quickstart, you:

  1. Create a Cloud Storage bucket to be the event source.

  2. Deploy an event receiver service to Cloud Run (fully managed).

  3. Create an event trigger.

  4. Generate an event by uploading a file to the Cloud Storage bucket, and view it in the Cloud Run (fully managed) logs.

Before you begin

  1. Sign in to your Google Account.

    If you don't already have one, sign up for a new account.

  2. In the Google Cloud Console, on the project selector page, select or create a Google Cloud project.

    Go to the project selector page

  3. Make sure that billing is enabled for your Cloud project. Learn how to confirm that billing is enabled for your project.

  4. Enable the Cloud Run, Cloud Logging, Cloud Build, Pub/Sub, Eventarc APIs.

    Enable the APIs

  5. When using the gcloud tool:
    1. Update gcloud components:
      gcloud components update
    2. Log in using your account:

      gcloud auth login

    3. Set the configuration variables used in this quickstart:

      gcloud config set project PROJECT_ID
      gcloud config set run/region us-central1
      gcloud config set run/platform managed
      gcloud config set eventarc/location us-central1

    4. Enable Cloud Audit Logs Admin Read, Data Read, and Data Write Log Types in Google Cloud Storage:

      Go to the Cloud Audit Logs console

    5. Grant the iam.serviceAccountTokenCreator role to the Pub/Sub service account:

      export PROJECT_NUMBER="$(gcloud projects describe $(gcloud config get-value project) --format='value(projectNumber)')"
      gcloud projects add-iam-policy-binding $(gcloud config get-value project) \

    6. Grant the eventarc.eventReceiver role to the Compute Engine service account:

      gcloud projects add-iam-policy-binding $(gcloud config get-value project) \
          --member=serviceAccount:${PROJECT_NUMBER}-compute@developer.gserviceaccount.com \

    7. Download and install the Git source code management tool.

Creating a Cloud Storage bucket

This quickstart uses Cloud Storage as the event source. To create a storage bucket:


  1. Go to Cloud Storage in the Cloud Console.

    Go to Cloud Storage

  2. Click Create bucket.

    New bucket.

  3. Enter your bucket information and click Continue to complete each step:

    • Enter a unique Name. For example, eventarcbucket.
    • Select Region as the Location Type.
    • Select us-central1 (Iowa) as the Location.
    • Select Standard for default storage class.
    • Select Uniform for Access control.
  4. Click Create.

Command line

gsutil mb -l us-central1 gs://events-quickstart-$(gcloud config get-value project)/

After the event source is created, you can deploy the event receiver service on Cloud Run (fully managed).

Deploying the event receiver service to Cloud Run (fully managed)

Deploy a Cloud Run (fully managed) service that receives and logs events. To deploy the sample event receiver service:


  1. Clone the python-docs-samples repository to your GitHub account:

    1. On GitHub, navigate to GoogleCloudPlatform/python-docs-samples.

    2. Click Fork.

      Screenshot of the fork button

    3. If prompted, select the location where you want to fork the repository.

  2. Go to Cloud Run in the Cloud Console.

    Go to Cloud Run

  3. Click Create service to display the Create service form.


  4. Select Cloud Run (fully managed).

  5. Select us-central1(Iowa) as the Region where you want your service located.

  6. Enter the desired service name. For example, helloworld-events.

  7. Click Next.

  8. Select Continuously deploy new revisions from a source repository.

  9. Click Set up with Cloud Build to open the Set up with Cloud Build form.

    Set up with Cloud Build page

    In the Set up with Cloud Build form:

    1. If prompted, enable the Cloud Build API and Container Analysis API.
    2. Select GitHub as the Repository Provider.

    3. If prompted, click Install Google Cloud Build.

    4. Select the GitHub repository you forked, python-docs-samples, as the Repository.

    5. Click Next.

    6. In the Branch field, enter ^master$.

    7. Select Dockerfile as the Build Type and provide the source location of the Dockerfile, eventarc/audit-storage/Dockerfile.

    8. Click Save.

  10. In the Create service form, click Next.

  11. In the Configure how this service is triggered section:

    • Select Allow all traffic.

    • Select Allow unauthenticated invocations.

  12. Optionally, click Add trigger and create a trigger or create a trigger after you create a service. For more information on creating a trigger, see Creating an Eventarc trigger.

  13. Click Create.

Command line

  1. Clone the repository:


    git clone https://github.com/GoogleCloudPlatform/python-docs-samples.git
    cd python-docs-samples/eventarc/audit-storage


    git clone https://github.com/GoogleCloudPlatform/java-docs-samples.git
    cd java-docs-samples/eventarc/audit-storage


    git clone https://github.com/GoogleCloudPlatform/golang-samples.git
    cd golang-samples/eventarc/audit_storage


    git clone https://github.com/GoogleCloudPlatform/nodejs-docs-samples.git
    cd nodejs-docs-samples/eventarc/audit-storage


    git clone https://github.com/GoogleCloudPlatform/dotnet-docs-samples.git
    cd dotnet-docs-samples/eventarc/audit-storage
  2. Build the container and upload it to Cloud Build:

    gcloud builds submit --tag gcr.io/$(gcloud config get-value project)/helloworld-events
  3. Deploy the container image to Cloud Run (fully managed):

    gcloud run deploy helloworld-events \
        --image gcr.io/$(gcloud config get-value project)/helloworld-events \

    When the deployment succeeds, the command line displays the service URL.

Now that you have deployed your event receiver service called helloworld-events to Cloud Run (fully managed), you can set up your trigger.

Creating an Eventarc trigger

The Eventarc trigger will send events from the Cloud Storage bucket to the helloworld-events Cloud Run (fully managed) service.


  1. Go to Cloud Run in the Cloud Console.

    Go to Cloud Run

  2. From the list of services, click the service you created, to go to its Service details page.

  3. Click the Triggers tab, and click Add trigger.

  4. In the Pick an event drop-down list, select Cloud Storage > storage.objects.create.

  5. In the Receive events from field, select Single region.

  6. Enable Cloud Audit Logs for the storage.googleapis.com service.

  7. If prompted, grant the eventarc.eventReceiver role to the Compute Engine service account and the iam.serviceAccountTokenCreator role to the Pub/Sub service account.

    Setting up a new trigger

  8. Click Save.

Command line

  1. Create a trigger that filters Cloud Storage events and that uses the Google Cloud project Compute Engine default service account:

    gcloud eventarc triggers create events-quickstart-trigger \
        --destination-run-service=helloworld-events \
        --destination-run-region=us-central1 \
        --event-filters="type=google.cloud.audit.log.v1.written" \
        --event-filters="serviceName=storage.googleapis.com" \
        --event-filters="methodName=storage.objects.create" \

    This creates a trigger called events-quickstart-trigger.

  2. To confirm events-quickstart-trigger was successfully created, run:

    gcloud eventarc triggers list --location=us-central1

    events-quickstart-trigger is displayed listed with a target of helloworld-events.

Generating and viewing an event

  1. To generate an event:


    1. Create a text file with the file name random.txt and the text "Hello World".

    2. Go to Cloud Storage in the Cloud Console.

      Go to Cloud Storage

    3. Select the storage bucket you created.

    4. In the Objects tab, click Upload files and upload the random.txt file.

    Command line

    Upload a text file to Cloud Storage:

    echo "Hello World" > random.txt
    gsutil cp random.txt gs://events-quickstart-$(gcloud config get-value project)/random.txt

    The upload generates an event and the Cloud Run (fully managed) service logs the event's message.

  2. To view the log entry:


    1. Go to Cloud Run in the Cloud Console.

      Go to Cloud Run

    2. From the list of services, click the name of the service you created to go to its Service details page.

    3. Click the Logs tab, to get the request and container logs for all revisions of this service. You can filter by log severity level.

    4. Look for a log entry similar to:

      Trigger logs

    Command line

    1. gcloud logging read "resource.type=cloud_run_revision AND resource.labels.service_name=helloworld-events"
    2. Look for a log entry similar to:

      Detected change in Cloud Storage bucket: storage.googleapis.com/projects/_/buckets/BUCKET_NAME/objects/random.txt

      where BUCKET_NAME is the name of the Cloud Storage bucket.

Congratulations! You have successfully deployed an event receiver service to Cloud Run (fully managed), created an Eventarc trigger, generated an event from Cloud Storage, and viewed it in the Cloud Run (fully managed) logs.

Clean up

While Cloud Run does not charge when the service is not in use, you might still be charged for storing the container image in Container Registry, Eventarc resources, and for storing files in your Cloud Storage bucket.

You can delete your image and delete your storage bucket. To delete the Eventarc trigger:

gcloud eventarc triggers delete events-quickstart-trigger

Alternatively, you can delete your Google Cloud project to avoid incurring charges. Deleting your Cloud project stops billing for all the resources used within that project.

  1. In the Cloud Console, go to the Manage resources page.

    Go to Manage resources

  2. In the project list, select the project that you want to delete, and then click Delete.
  3. In the dialog, type the project ID, and then click Shut down to delete the project.

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