Quickstart: Receiving events using Cloud Audit Logs (gcloud command-line tool)

This quickstart shows you how to receive events from Cloud Storage in an unauthenticated Cloud Run service using Eventarc.

You can complete this quickstart using the gcloud command-line tool. For instructions using the console, see Using the console to receive events with Cloud Audit Logs.

In this quickstart, you:

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

  2. Deploy an event receiver service to Cloud Run.

  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 logs.

Before you begin

  1. Sign in to your Google Cloud account. If you're new to Google Cloud, create an account to evaluate how our products perform in real-world scenarios. New customers also get $300 in free credits to run, test, and deploy workloads.
  2. In the Google Cloud Console, on the project selector page, select or create a Google Cloud project.

    Go to project selector

  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. Update gcloud components:
    gcloud components update
  6. Log in using your account:

    gcloud auth login

  7. 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

  8. Enable Cloud Audit Logs Admin Read, Data Read, and Data Write Log Types in Google Cloud Storage:
    1. Read your project's IAM policy and store it in a file:
       gcloud projects get-iam-policy PROJECT_ID > /tmp/policy.yaml
    2. Edit your policy in /tmp/policy.yaml, adding or changing only the Data Access audit logs configuration.

      - auditLogConfigs:
        - logType: ADMIN_READ
        - logType: DATA_WRITE
        - logType: DATA_READ
        service: storage.googleapis.com
      - members:
        - user:EMAIL_ADDRESS
        role: roles/owner
      etag: BwW_bHKTV5U=
      version: 1
      • Replace EMAIL_ADDRESS with your email address.
    3. Write your new IAM policy:
      gcloud projects set-iam-policy PROJECT_ID /tmp/policy.yaml
      If the preceding command reports a conflict with another change, then repeat these steps, starting with reading the project's IAM policy.
  9. Grant the eventarc.eventReceiver role to the Compute Engine service account:
    export PROJECT_NUMBER="$(gcloud projects describe $(gcloud config get-value project) --format='value(projectNumber)')"
    gcloud projects add-iam-policy-binding $(gcloud config get-value project) \
        --member=serviceAccount:${PROJECT_NUMBER}-compute@developer.gserviceaccount.com \

  10. If you enabled the Pub/Sub service account on or before April 8, 2021, grant the iam.serviceAccountTokenCreator role to the Pub/Sub service account:

    gcloud projects add-iam-policy-binding $(gcloud config get-value project) \

  11. 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:

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.

Deploying the event receiver service to Cloud Run

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

  1. Clone the repository:


    git clone https://github.com/GoogleCloudPlatform/golang-samples.git
    cd golang-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/dotnet-docs-samples.git
    cd dotnet-docs-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/python-docs-samples.git
    cd python-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:

     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, 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 service.

  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:

    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 service logs the event's message.

  2. To view the log entry:

    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, created an Eventarc trigger, generated an event from Cloud Storage, and viewed it in the Cloud Run 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.

gcloud projects delete PROJECT_ID_OR_NUMBER
  • Replace PROJECT_ID_OR_NUMBER with the project ID or number.

What's next