Jenkins Declarative Pipeline: How to inject properties

Question

I have Jenkins 2.19.4 with Pipeline: Declarative Agent API 1.0.1. How does one use readProperties if you cannot define a variable to assign properties read to?

For e

Answer 1

You can use the script step inside the steps tag to run arbitrary pipeline code.

So something in the lines of:

pipeline {
    agent any
    stages {
        stage('A') {
            steps {
                writeFile file: 'props.txt', text: 'foo=bar'
                script {
                    def props = readProperties file:'props.txt';
                    env['foo'] = props['foo'];
                }
            }
        }
        stage('B') {
            steps {
                echo env.foo
            }
        }
    }
}

Here I'm using env to propagate the values between stages, but it might be possible to do other solutions.

Answer 2

The @jon-s solution requires granting script approval because it is setting environment variables. This is not needed when running in same stage.

pipeline {
  agent any
  stages {
    stage('A') {
      steps {
        writeFile file: 'props.txt', text: 'foo=bar'
        script {
           def props = readProperties file:'props.txt';
        }
        sh "echo $props['foo']"
      }
    }
  }
}

Answer 3

To define general vars available to all stages, define values for example in props.txt as:

version=1.0
fix=alfa

and mix script and declarative Jenkins pipeline as:

def props
def VERSION
def FIX
def RELEASE

node {
   props = readProperties file:'props.txt'
   VERSION = props['version']
   FIX = props['fix']
   RELEASE = VERSION + "_" + FIX
}

pipeline {
   stages {
      stage('Build') {
         echo ${RELEASE}
      }
   }
}