set_pipeline step supports detach mode

[evanchaoli]

Changes proposed by this PR

If jobA of pipelineA call set_pipeline step to set pipelineB, then jobA is pipelineB's parent job. Currently Concourse has a logic that, if jobA sets another pipeline than pipelineB, then pipelineB will be automatically archived, which helps prevent from orphan pipelines.

set_pipeline step supports parameter team only when parent job runs from main team. We have a use case where a service pipeline running from main team may set child parent pipelines per needs. In other words, build-1 may set a child pipeline to teamA, then build-2 may set another child pipeline to teamB, and so on ... The behavior will trigger auto pipeline archive, thus this use case doesn't work with set_pipeline step.

I think my use case makes sense from main team. To not break the current logic, I am adding a detach flag to set_pipeline step. A parent job needs to explicitly turn on the flag so that child pipeline will be set in detach mode (same as set via fly set-pipeline, so that child pipeline will never be auto archived.

• done

Notes to reviewer

Release Note

• Add detach flag to set_pipeline step. Only the main team can set child pipelines in detach mode. In detach mode, child pipelines will never be automatically archived.

[timota]

any plans to add this feature to concourse? It will be extremely useful.