Pipelines: can pipeline triggers trigger parameterised pipelines?

Paul Hicks

I've been trying out triggered pipelines (using the `triggers` section, as opposed to traditional selectors under `pipelines`). For simple custom pipelines it's working great, but I'd now like to invoke a custom pipeline with variables. Consider this sort of custom pipeline:

    check-environment:
      - variables:
          - name: env
            default: dev
            allowed-values:
              - dev
              - test
              - prod
      - step:
          - script: # ...

If the `variables` section isn't there, then this trigger works:

triggers:
  pullrequest-push:
    - condition: *anyChange
      pipelines:
        - check-environment

But since the `pipelines` array is defined to be strings, I can't do anything "intuitive" like this:

triggers:
  pullrequest-push:
    - condition: *anyChange
      pipelines:
        - pipeline:
             name: check-environment
             variables:
               - env: test

Is there a way to invoke the custom pipeline above from a pipeline trigger like this? What is the syntax? A link to the docs would be great, too.

Paul Hicks

I have come up with a workaround that I'll call "deparameterisation". Using child pipeline input variables, you can hard code parameters into parent pipelines:

    check-environment:
      - variables:
          - name: env
            default: dev
            allowed-values:
              - dev
              - test
              - prod

      - step:
          script: # ...


    check-environment-dev:
      steps:
        - step:
            name: Run `check-environemnt` against dev
            type: pipeline
            custom: check-environment
            input-variables:
              env: dev

    check-environment-test:
      steps:
        - step:
            name: Run `check-environemnt` against test
            type: pipeline
            custom: check-environment
            input-variables:
              env: test

It is reasonably horrendous, creating a plethora of nearly-meaningless custom pipelines, but at least the script is DRY. Until the `triggers` section supports pipelines as something more than plain strings, I think this will have to do