Jenkinsfile & Environment Variables in Jenkins (Part 3/4) — Belajar Git & CI/CD

1. Variabel Lingkungan Bawaan (Built-in Env Vars)

Jenkins menyediakan variabel sistem bawaan yang dapat langsung diakses di dalam pipeline:

${env.BUILD_NUMBER}: Nomor urut build saat ini (misal: 42).
${env.BRANCH_NAME}: Nama cabang Git yang sedang diproses.
${env.JOB_NAME}: Nama job Jenkins.
${env.GIT_COMMIT}: Hash SHA commit Git yang memicu build.

2. Parameterized Pipeline & Credentials Binding

Jenkinsfile Advanced Example

pipeline {
    agent any

    parameters {
        choice(name: 'DEPLOY_ENV', choices: ['staging', 'production'], description: 'Pilih Lingkungan Target Deployment')
        booleanParam(name: 'RUN_INTEGRATION_TESTS', defaultValue: true, description: 'Jalankan Integration Test?')
    }

    environment {
        DOCKER_REGISTRY = 'registry.hub.docker.com/myuser'
        DB_SECRET = credentials('postgres-production-cred')
    }

    stages {
        stage('Build & Deploy') {
            steps {
                echo "Deploying branch ${BRANCH_NAME} build #${BUILD_NUMBER} to ${params.DEPLOY_ENV}..."
                
                withCredentials([usernamePassword(credentialsId: 'docker-hub-auth', usernameVariable: 'USER', passwordVariable: 'PASS')]) {
                    sh "docker login -u ${USER} -p ${PASS}"
                }
            }
        }
    }
}