Receive events using Cloud Audit Logs (gcloud CLI)

This quickstart shows you how to set up a Google Kubernetes Engine (GKE) service as a destination to receive events from Cloud Storage using Eventarc.

In this quickstart, you will:

  1. Set up a service account so that Eventarc can pull events and forward it to the target.
  2. Create a Cloud Storage bucket to be the event source.
  3. Create a GKE cluster.
  4. Initialize GKE destinations in Eventarc.
  5. Deploy a GKE service that receives events.
  6. Create an Eventarc trigger that sends events from Cloud Storage to the GKE service.
  7. Upload a file to the Cloud Storage bucket to generate an event and view the event in the GKE pod 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. Install the Google Cloud CLI.
  3. To initialize the gcloud CLI, run the following command:

    gcloud init
  4. Create or select a Google Cloud project.

    • Create a Google Cloud project:

      gcloud projects create PROJECT_ID

      Replace PROJECT_ID with a name for the Google Cloud project you are creating.

    • Select the Google Cloud project that you created:

      gcloud config set project PROJECT_ID

      Replace PROJECT_ID with your Google Cloud project name.

  5. Make sure that billing is enabled for your Google Cloud project.

  6. Install the Google Cloud CLI.
  7. To initialize the gcloud CLI, run the following command:

    gcloud init
  8. Create or select a Google Cloud project.

    • Create a Google Cloud project:

      gcloud projects create PROJECT_ID

      Replace PROJECT_ID with a name for the Google Cloud project you are creating.

    • Select the Google Cloud project that you created:

      gcloud config set project PROJECT_ID

      Replace PROJECT_ID with your Google Cloud project name.

  9. Make sure that billing is enabled for your Google Cloud project.

  10. Update Google Cloud CLI components:
    gcloud components update
  11. Enable the Eventarc, Resource Manager, and Google Kubernetes Engine APIs:
    gcloud services enable eventarc.googleapis.com \
        cloudresourcemanager.googleapis.com \
        container.googleapis.com
  12. Set the configuration variables used in this quickstart:
    PROJECT_ID=$(gcloud config get-value project)
    TRIGGER_SA=eventarc-sa
    CLUSTER_NAME=events-cluster
    SERVICE_NAME=hello-gke
  13. If you are the project creator, you are granted the basic Owner role (roles/owner). By default, this Identity and Access Management (IAM) role includes the permissions necessary for full access to most Google Cloud resources and you can skip this step.

    If you are not the project creator, required permissions must be granted on the project to the appropriate principal. For example, a principal can be a Google Account (for end users) or a service account (for applications and compute workloads). For more information, see the Roles and permissions page for your event destination.

    Required permissions

    To get the permissions that you need to complete this quickstart, ask your administrator to grant you the following IAM roles on your project:

    For more information about granting roles, see Manage access to projects, folders, and organizations.

    You might also be able to get the required permissions through custom roles or other predefined roles.

  14. Make note of the Compute Engine default service account as you will you attach it to an Eventarc trigger to represent the identity of the trigger for testing purposes. This service account is automatically created after enabling or using a Google Cloud service that uses Compute Engine, and with the following email format:

    PROJECT_NUMBER-compute@developer.gserviceaccount.com
    

    Replace PROJECT_NUMBER with your Google Cloud project number. You can find your project number on the Welcome page of the Google Cloud console or by running the following command:

    gcloud projects describe PROJECT_ID --format='value(projectNumber)'

    For production environments, we strongly recommend creating a new service account and granting it one or more IAM roles that contain the minimum permissions required and follow the principle of least privilege.

  15. Grant the Pub/Sub Subscriber role (roles/pubsub.subscriber) on the project to the Compute Engine default service account so that the Eventarc trigger can pull events from Pub/Sub.
    gcloud projects add-iam-policy-binding PROJECT_ID \
        --member=serviceAccount:PROJECT_NUMBER-compute@developer.gserviceaccount.com \
        --role=roles/pubsub.subscriber
  16. Grant the Eventarc Event Receiver role (roles/eventarc.eventReceiver) on the project to the Compute Engine default service account so that the Eventarc trigger can receive events from event providers.
    gcloud projects add-iam-policy-binding PROJECT_ID \
        --member=serviceAccount:PROJECT_NUMBER-compute@developer.gserviceaccount.com \
        --role=roles/eventarc.eventReceiver
  17. If you enabled the Cloud Pub/Sub service agent on or before April 8, 2021, to support authenticated Pub/Sub push requests, grant the Service Account Token Creator role (roles/iam.serviceAccountTokenCreator) to the service agent. Otherwise, this role is granted by default:
    gcloud projects add-iam-policy-binding PROJECT_ID \
        --member=serviceAccount:service-PROJECT_NUMBER@gcp-sa-pubsub.iam.gserviceaccount.com \
        --role=roles/iam.serviceAccountTokenCreator
  18. For Google Cloud Storage, enable log types for these services: Admin Read, Data Read, and Data Write:

    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. Caution: You must preserve the `bindings:` and `etag:` sections without changes. Failure to do so might cause your project to become unusable.
      auditConfigs:
        - auditLogConfigs:
          - logType: ADMIN_READ
          - logType: DATA_WRITE
          - logType: DATA_READ
          service: storage.googleapis.com
        bindings:
        - 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.

Create a Cloud Storage bucket

This quickstart uses Cloud Storage as the event source. Create a Cloud 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 GKE.

Create a GKE cluster

A GKE cluster consists of at least one cluster control plane machine and multiple worker machines called nodes. Nodes are Compute Engine virtual machine (VM) instances that run the Kubernetes processes necessary to make them part of the cluster. You deploy applications to clusters, and the applications run on the nodes.

Create an Autopilot cluster named events-cluster:

gcloud container clusters create-auto $CLUSTER_NAME --region us-central1

It might take several minutes for the creation of the cluster to complete. Once the cluster is created, the output should be similar to the following:

Creating cluster events-cluster...done.
Created [https://container.googleapis.com/v1/projects/MY_PROJECT/zones/us-central1/clusters/events-cluster].
[...]
STATUS: RUNNING

This creates a GKE cluster named events-cluster in a project with a Google Cloud project ID of MY_PROJECT.

Enable GKE destinations

For each trigger that targets a GKE service, Eventarc creates an event forwarder component that pulls events from Pub/Sub and forwards it to the target. To create the component and manage resources in the GKE cluster, grant permissions to the Eventarc service agent:

  1. Enable GKE destinations for Eventarc:

    gcloud eventarc gke-destinations init
    
  2. At the prompt to bind the required roles, enter y.

    The following roles are bound to the service account:

    • compute.viewer
    • container.developer
    • iam.serviceAccountAdmin

Create a GKE service destination

Deploy a GKE service that will receive and log events using a prebuilt image, us-docker.pkg.dev/cloudrun/container/hello:

  1. Kubernetes uses a YAML file called kubeconfig to store cluster authentication information for kubectl. Update the kubeconfig file with credentials and endpoint information to point kubectl at the GKE cluster:

    gcloud container clusters get-credentials $CLUSTER_NAME \
        --region us-central1
    
  2. Create a Kubernetes deployment:

    kubectl create deployment $SERVICE_NAME \
        --image=us-docker.pkg.dev/cloudrun/container/hello
    
  3. Expose it as a Kubernetes service:

    kubectl expose deployment $SERVICE_NAME \
        --type ClusterIP --port 80 --target-port 8080
    

Create an Eventarc trigger

When you upload a file to Cloud Storage, the Eventarc trigger sends events from Cloud Storage to the hello-gke GKE service.

  1. Create a Cloud Audit Logs trigger:

    gcloud eventarc triggers create my-gke-trigger \
        --location="us-central1" \
        --destination-gke-cluster="events-cluster" \
        --destination-gke-location="us-central1" \
        --destination-gke-namespace="default" \
        --destination-gke-service="hello-gke" \
        --destination-gke-path="/" \
        --event-filters="type=google.cloud.audit.log.v1.written" \
        --event-filters="serviceName=storage.googleapis.com" \
        --event-filters="methodName=storage.objects.create" \
        --service-account="PROJECT_NUMBER-compute@developer.gserviceaccount.com"
    

    This creates a trigger called my-gke-trigger.

  2. Confirm that the trigger was successfully created:

    gcloud eventarc triggers list
    

    The output should be similar to the following:

    NAME: my-gke-trigger
    TYPE: google.cloud.audit.log.v1.written
    DESTINATION: GKE: hello-gke
    ACTIVE: By 20:39:43
    LOCATION: us-central1
    

Generate and view an event

Upload a text file to Cloud Storage to generate an event and trigger the GKE service. You can then view the event's message in the pod logs.

  1. 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 GKE pod logs the event's message.

  2. To view the event message:

    1. Find the pod ID:

      kubectl get pods

      The output should be similar to the following:

      NAME                                         READY   STATUS             RESTARTS   AGE
      hello-gke-645964f578-2mjjt                   1/1     Running            0          35s

      Copy the NAME of the pod to use in the next step.

    2. Check the logs of the pod:

      kubectl logs NAME

      Replace NAME with the name of the pod you copied.

    3. Look for a log entry similar to:

      2022/02/24 22:23:49 Hello from Cloud Run! The container started successfully and is listening for HTTP requests on $PORT
      {"severity":"INFO","eventType":"google.cloud.audit.log.v1.written","message":"Received event of type google.cloud.audit.log.v1.written. [...]}
      

Clean up

When you finish the tasks that are described in this document, you can avoid continued billing by deleting the resources that you created.

You can:

  1. Delete the Cloud Storage bucket.

  2. Delete the Eventarc trigger.

  3. Delete the GKE cluster.

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

Delete a Google Cloud project:

gcloud projects delete PROJECT_ID

If you plan to explore multiple tutorials and quickstarts, reusing projects can help you avoid exceeding project quota limits.

What's next

Receive events using Pub/Sub (Google Cloud CLI)