Working with the environment

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Jenkins Pipeline exposes environment variables via the global variable env, which is available from anywhere within a Jenkinsfile. The full list of environment variables accessible from within Jenkins Pipeline is documented at http://localhost:8080/pipeline-syntax/globals#env, assuming a Jenkins controller is running on localhost:8080, and includes:

BUILD_ID

The current build ID, identical to BUILD_NUMBER for builds created in Jenkins versions 1.597+

JOB_NAME

Name of the project of this build, such as "foo" or "foo/bar".

JENKINS_URL

Full URL of Jenkins, such as http://example.com:port/jenkins/ (NOTE: only available if Jenkins URL is set in "System Configuration".)

Referencing or using these environment variables can be accomplished like accessing any key in a Groovy Map, for example:

// Declarative //
pipeline {
    agent any
    stages {
        stage('Example') {
            steps {
                echo "Running ${env.BUILD_ID} on ${env.JENKINS_URL}"
            }
        }
    }
}
// Script //
node {
    echo "Running ${env.BUILD_ID} on ${env.JENKINS_URL}"
}

Setting environment variables

Setting an environment variable within a Jenkins Pipeline is accomplished differently depending on whether Declarative or Scripted Pipeline is used.

Declarative Pipeline supports an environment directive, whereas users of Scripted Pipeline must use the withEnv step.

// Declarative //
pipeline {
    agent any
    environment { (1)
        CC = 'clang'
    }
    stages {
        stage('Example') {
            environment { (2)
                DEBUG_FLAGS = '-g'
            }
            steps {
                sh 'printenv'
            }
        }
    }
}
// Script //
node {
    /* .. snip .. */
    withEnv(["PATH+MAVEN=${tool 'M3'}/bin"]) {
        sh 'mvn -B verify'
    }
}
1 An environment directive used in the top-level pipeline block will apply to all steps within the Pipeline.
2 An environment directive defined within a stage will only apply the given environment variables to steps within the stage.