Build errors out with below output (Using a Rails app)
ERROR: (gcloud.app.deploy) There is a cloudbuild.yaml in the current directory, and the runtime field in /workspace/app.yaml is currently set to [runtime: ruby]. To use your cloudbuild.yaml to build a custom runtime, set the runtime field to [runtime: custom]. To continue using the [ruby] runtime, please remove the cloudbuild.yaml from this directory.
Cloudbuild.yaml should work with App Engine Flexible without the need to use a custom runtime. As detailed in the error message, you cannot have the app.yaml and the cloudbuild.yaml in the same directory if you are deploying in a non-custom runtime, to remedy the situation, follow these steps:
Move the app.yaml and other ruby files into a subdirectory (use your original app.yaml, no need to use custom runtime)
Under your cloudbuild.yaml steps, modify the argument for app deploy by adding a third one specifying the app.yaml path.
Below is an example:
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