Rollback apps with the new deployment setup

We in the process of updating the Concourse deployment pipelines. In the future, they will now use the deployment-bag resource to track app versions as they are created, tested and deployed across the environments. This allows for a straightforward process to rollback as previous deployment-bag versions can be pinned and re-deployed.

In deploy-notify pipelines, here is the deploy pipeline:

Here is the pack-bag pipeline: python-client-tests-image is currently pinned and won't be updated in this environment.

Individual apps or previous bag deployments as a whole can be pinned in Concourse. This requires at least the pipeline operator role.

Click the pin icon on a previous version:

This will not redeploy immediately, the pack-bag job must be manually repacked using the trigger a new build button on the pack-bag job. This will then go on to trigger the bag deployment.

If reverting to a previous bag version, the start-deploy job can be manually triggered once the previously deployed bag has been pinned.

You can check the image digest being run in the AWS Console to confirm the rollback has completed. This is visible from the ECS Task container overview. For example, a snippet image below.