Scheduled service

You can use Cloud Scheduler to securely trigger a Cloud Run service on a schedule, similar to cron jobs. You can read more about this in Cloud Run docs.

Enable Cloud Scheduler

First, make sure the Cloud Scheduler service is enabled in your project:

gcloud services enable cloudscheduler.googleapis.com

Create a 'Event Display' service

Take a look at the service we already created in event-display folder. It simply logs out the HTTP request body. We'll use it to display the received messages.

Build the container

In folder where Dockerfile resides, build the container using Cloud Build and push it to Container Registry:

gcloud builds submit \
  --project ${PROJECT_ID} \
  --tag gcr.io/${PROJECT_ID}/event-display

Deploy to Cloud Run

Note that we're deploying with no-allow-unauthenticated flag. We only want Cloud Scheduler to trigger the service:

export SERVICE_NAME=event-display-scheduled

gcloud run deploy ${SERVICE_NAME} \
  --image gcr.io/${PROJECT_ID}/event-display \
  --platform managed \
  --no-allow-unauthenticated

Setup Cloud Scheduler to trigger Cloud Run

Create a service account:

export SERVICE_ACCOUNT=cloudrun-scheduler-sa

gcloud iam service-accounts create ${SERVICE_ACCOUNT} \
   --display-name "Cloud Run Scheduler Service Account"

Give service account permission to invoke the Cloud Run service:

gcloud run services add-iam-policy-binding event-display-scheduled \
   --member=serviceAccount:${SERVICE_ACCOUNT}@${PROJECT_ID}.iam.gserviceaccount.com \
   --role=roles/run.invoker

Create a job

Create a Cloud Scheduler job to execute every 5 minutes:

export SERVICE_URL="$(gcloud run services list --platform managed --filter=${SERVICE_NAME} --format='value(URL)')"

gcloud beta scheduler jobs create http cloudrun-job --schedule "*/5 * * * *" \
   --http-method=POST \
   --uri=${SERVICE_URL} \
   --oidc-service-account-email=${SERVICE_ACCOUNT}@${PROJECT_ID}.iam.gserviceaccount.com \
   --oidc-token-audience=${SERVICE_URL}

Test the service

You can check the logs of the service to see that it's been triggered by the Cloud Scheduler every 5 mins:

12:15:00.578 GMT POST 200 188 B 100 ms Google-Cloud-Scheduler https://event-display-scheduled-pbelpl5x6a-ew.a.run.app/

12:20:00.641 GMT POST 200 188 B 32 ms Google-Cloud-Scheduler https://event-display-scheduled-pbelpl5x6a-ew.a.run.app/