Pass variables across Jenkins Multi-Branch Declarative Pipeline Projects

Question

I have project A and project B. I would like to pass parameters (like the BranchName and ArtifactoryID) from project A to project B. Both are multi-branch pipelines using a Declarative Script Jenkinsfile.

When I use the Snippet Generator it tells me the project "is not parameterized". When looking at the config of the multi-branch pipeline, I don't see a way to parameterize it. What am I missing? (see attached)

A google result shows this, but I'm not sure how it's supposed to pass params between multi-branch pipelines: https://issues.jenkins-ci.org/browse/JENKINS-32780

Answer 1

I figured this out. I leveraged an answer from a comment here: Pipeline pass parameters to downstream jobs

For a detailed explanation using my example shown above, my Project A jenkinsfile would have the following before the stages:

  parameters
  {
    string(name: 'BRANCH_PASSED_OVER', defaultValue: '${env.BRANCH_NAME}', description: 'pass branch value')
    string(name: 'PERSON2', defaultValue: 'Mr Jenkins', description: 'Who should I say hello to?')
  }

...and the following for the build step phase

  stage('Build downstream')
  {
    steps
    {
    build job: 'BUILD/CMTest2/' + env.BRANCH_NAME.replaceAll("/", "%2F"), wait: false, parameters: [string(name: 'PERSON2', value: params.PERSON2), string(name: 'PASS_BRANCH_NAME', value: env.BRANCH_NAME)]
    }
  }

In Project B then in my jenkinsfile I could call the param like so:

  stage('Collect Info')
  {
    steps
    {
      echo "Hello ${params.PERSON2}"
      echo "PASS_BRANCH_NAME: ${params.PASS_BRANCH_NAME}"
    }
  }