[JENKINS-42373] introduce StageListener

[ndeloof]

JENKINS-42373

[ndeloof]

@reviewbybees

[ghost]

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[jglick]

No JIRA, no downstream PR demonstrating implementation, no description at all of what the purpose might be.

Anyway this is dead code unless you are using non-block-scoped stages, which is now deprecated.

[jglick]

typo

[ndeloof]

@jglick sample usage is in private code
created JENKINS-42373 to track this
I indeed didn't noticed the "block" part, I don't use this mode by myslef, I dislike it :P

[jglick]

We already have FlowGraphListener which gives you much more information and is not limited to this step, so this API seems superfluous.

[ndeloof]

I never heard about this guy. HAve a link to FlowGraphListener.java ? github nor Google do know about it

[jglick]

GraphListener, sorry.

[ndeloof]

ok, thanks. Will need to understand how to use it.

[svanoort]

@ndeloof Also there is a set of APIs in the workflow-api graphanalysis package and pipeline-graph-analysis plugin if you need to pick out stage information and do something with it.