pre-deploy-job.md

Pre-deploy Cloud Run job

The 8.0.0 release introduced the enable_pre_deploy_job variable which, when set to true, creates a Cloud Run job to execute a configurable command before new Cloud Run service revisions are deployed. This is a useful way to run database migrations and other commands which are tightly coupled to the release cadence of the main Cloud Run service.

The pre-deploy job is configured via the pre_deploy_job_* variables which can be found in variables.tf.

Triggering the Cloud Run job

The Cloud Run job is executed by a null_resource resource which simply runs the gcloud run jobs execute command. The null_resource is triggered each time the var.pre_deploy_job_container.image value changes by default, although you can force it to run via the pre_deploy_job_force variable.

Order of operations

To ensure that the pre-deploy job runs before a new revision of the Cloud Run service is deployed, the resources in question are explicitly configured with depends_on relationships as follows.

• The google_cloud_run_v2_job.pre_deploy Cloud Run job has no depends_on relationships defined and is therefore deployed first.
• The null_resource.pre_deploy_job_trigger resource depends on google_cloud_run_v2_job.pre_deploy and therefore won't be deployed until the Cloud Run job is deployed successfully.
• Finally, the google_cloud_run_service.webapp Cloud Run service depends on null_resource.pre_deploy_job_trigger, meaning it is only deployed once the null_resource.pre_deploy_job_trigger has executed successfully.