Jenkins declarative pipeline lock name with variable

Question

I have a declarative Jenkins Pipeline with a lock, eg

pipeline {
    environment {
        BRANCH = 'master'
    }
    agent any
    stages{
        stage('stage') {
            options {
                lock(resource: "lock-${env.BRANCH}")
            }
            steps {
                echo "Something"
            }
        }
    }
}

But when I execute the pipeline, in the log it says

[Pipeline] lock
Trying to acquire lock on [lock-null]
Lock acquired on [lock-null]
[Pipeline] {
[Pipeline] echo
master
[Pipeline] }
Lock released on resource [lock-null]

The environment variable seems to be not set when the lock-name is evaluated, but when the echo argument is evaluated, it is set correctly.

This answer to a somewhat related question gave the hint to use a lazily evaluated GString instead of a normal GString. Trying this:

pipeline {
    environment {
        BRANCH = 'master'
    }
    agent any
    stages{
        stage('stage') {
            options {
                lock(resource: "lock-${->env.BRANCH}" as String)
            }
            steps {
                echo "${->env.BRANCH}" as String
            }
        }
    }
}

gives me the following log messages

[Pipeline] lock
Trying to acquire lock on [[no resource/label specified - probably a bug]]
Lock acquired on [[no resource/label specified - probably a bug]]
[Pipeline] {
[Pipeline] echo
master
[Pipeline] }
Lock released on resource [[no resource/label specified - probably a bug]]

So, it looks like the variable can't be resolved correctly.

The problem I want to solve is, creating a multibranch-pipeline which has a lock on a stage. But when the lock has a name, which is not dependend on the branchname, only one branch of the pipeline can run in parallel in this stage.

How can I solve this?

Answer 1

You could just use lock as a step instead of an option :

pipeline {
    environment {
        BRANCH = 'master'
    }
    agent any
    stages{
        stage('stage') {
            steps {
                lock("lock-${env.BRANCH}" as String) {
                    echo "${env.BRANCH}" as String
                }
            }
        }
    }
}

As within steps the variable env.BRANCH is set, this should work.

Also see documentation for lock step .

Answer 2

I recently ran into this myself. ${env} is not accessible in the options block, but ${currentBuild} is. So what I did was first was println("$currentBuild") and get the name of the class. From that, I googled the Java source code docs and followed the functions until I got what I needed.

In my case, I wanted the ${env.NODE_NAME} and I ended up with ${currentBuild.getRawBuild().getExecutor().getOwner().getDisplayName()}