Jenkins env vars do not work with Pipeline Plugin about percy-client

[NahidSiddiqui]

I am using pipeline and was wondering how I can trigger off builds from multibranch pipeline project but some reason I cannot get the value for CHANGE_ID for a branch that has a pending pull request active. I use a Jenkins file that is stored in the repo and I was looking to trigger off builds using the code in the Jenkins file which needs to detect the pull request using CHANGE_ID. I tried using sh " echo env.CHANGE_ID" but this returns null. However I do get a value for sh "echo env.BRANCH_NAME".

[fotinakis]

Hey @jonesetc — thanks for this info, very helpful.

Before we update this and our other client libraries to natively support it, can you use our override variables to make sure things work in your Pipeline Plugin environment?

export PERCY_PULL_REQUEST="$CHANGE_ID"
export PERCY_BRANCH ="$BRANCH_NAME"

If the commit SHA is no longer stored in GIT_COMMIT, you'll also need to export PERCY_COMMIT="$SOME_PIPELINE_ENV_VAR_FOR_COMMIT_SHA"

If that works for you, we can update our libraries to check if Pipeline is used vs. GHPRB.

[jonesetc]

Thanks for the quick response.

Setting PERCY_BRANCH to $BRANCH_NAME works and is what we started doing to work around our issue of master builds not being recognized as such. I will do a little bit of testing to set those other two variables and make sure.

I'm guessing that if PERCY_PULL_REQUEST is set correctly, the UI for the build will have a link back to that PR?

[fotinakis]

Yup!

[jonesetc]

So, I did a little bit of testing, and here's the general information:

• BRANCH_NAME is a replacement for ghprbTargetBranch, and is always available
• CHANGE_ID is a replacement for ghprbPullId, but is not always available
  • The Pipeline Plugin can be configured to build all branches, not just PRs, and as such does not usually have this set on the env
• There is no available variable that serves the same information as GIT_COMMIT, so it would require the fallback to parsing raw git output
  • The Pipeline Plugin is built abstractly from all SCM systems, so specific things like commits are not available in the environment
  • The commit hash is available elsewhere to the user, but would still require the user to manually set it on the environment

I'd be happy to make a PR for this that would basically:

• Add a new current_ci tag called :jenkins-pipeline
• _commit_sha would still fall through and use the _raw_commit_output('HEAD')
• branch would use ENV['BRANCH_NAME']
• pull_request_number would use ENV['CHANGE_ID'] if available

[fotinakis]

👍 Sounds good to us, @jonesetc! Thanks for doing that research as well.