Limit which branch is built by Jenkins pipeline?

Question

I am currently configuring a Jenkins server hosted on a Docker container in AWS.

I am using BlueOcean to configure a repository.

Right now, the pipeline scans all branches on a repository to detect Jenkinsfiles and then will automatically build on that branch if it detects changes. I scan the repo every 5 minutes to detect changes.

However, I do not want to be running builds and jobs automatically if it is some random feature branch. I am trying to limit the automatically triggered builds to only changes in staging and master branches.

So my question is, how/where do you configure Jenkins GitHub pipeline to only build on certain branches rather than scanning all branches?

Answer 1

A Multibranch pipeline job is your friend.

Rather than trying to limit which branches Jenkins is polling firstly what I do in my Jenkinsfile is poll source control every minute:

triggers { pollSCM('* * * * *') }

This will poll every branch and create a job where it finds a Jenkinsfile in the location and name you specify in the Multibranch Pipeline job configuration.

Side Note

About the only configuration in a multibranch pipeline is:

1. Where's the SCM repo?
2. Workspace relative path and name of Jenkinsfile. (You can call it Bob if you want)

A multibranch pipeline job sets an additional environment variable: BRANCH_NAME which allows you to conditionally perform actions in pipeline like so:

script {
    if( "${env.BRANCH_NAME}" == "integration" ) {
        //Do something useful
    }
}

Using this method you can also decide to do nothing in response to a poll event.