Jenkins Pipeline Example Code

condition

How to apply conditions aka Flow Control in jenkins scripted pipeline?
========================================================

node {
    stage('Example') {
        if (env.BRANCH_NAME == 'master') {
            echo 'I only execute on the master branch'
        } else {
            echo 'I execute elsewhere'
        }
    }
}

  stage('UT') {
      // Run the maven build
      if (isUnix()) {
         sh "'${mvnHome}/bin/mvn' -Dmaven.test.failure.ignore clean test"
      } else {
         bat(/"${mvnHome}\bin\mvn" -Dmaven.test.failure.ignore clean test/)
      }
   }

jenkinsfile

decalartive Pipeline
===================================
pipeline {
    agent { docker { image 'maven:3.3.3' } }
    stages {
        stage('build') {
            steps {
                sh 'mvn --version'
            }
        }
    }
}

Scripted Pipeline

node {
        stage('Build') 
	   {
            sh 'echo rajesh'
        }
    }



node {
        stage('Build') 
	   {
         	sh "echo Build"
        }
        stage('Deploy') 
	   {
         	sh "echo Deploy"
        }
        stage('Test') 
	   {
         	sh "echo Test"
        }
    }


node {
        stage('Build') 
	   {
		git 'https://github.com/devopsschool-demo-labs-projects/helloworld-java-maven'
         	sh "echo Build"
        }
        stage('Deploy') 
	   {
         	sh "echo Deploy"
        }
        stage('Test') 
	   {
         	sh "echo Test"
        }
    }

# This code would run in a node called 'linux'
node('linux') {
        stage('Build') 
	   {
		git 'https://github.com/devopsschool-demo-labs-projects/helloworld-java-maven'
         	sh "echo Build"
        }
        stage('Deploy') 
	   {
         	sh "echo Deploy"
        }
        stage('Test') 
	   {
         	sh "echo Test"
        }
    }


node {
	   def mvnHome
        stage('Build') 
	   {
		git 'https://github.com/devopsschool-demo-labs-projects/helloworld-java-maven'
         	sh "echo Build"
          mvnHome = tool 'rajesh-maven'
          sh "'${mvnHome}/bin/mvn' clean compile" 
        }
        stage('Deploy') 
	   {
         	sh "echo Deploy"
        }
        stage('Test') 
	   {
         	sh "echo Test"
          sh "'${mvnHome}/bin/mvn' clean test" 
        }
    }

node {
	   def mvnHome
        stage('Build') 
	   {
		git 'https://github.com/devopsschool-demo-labs-projects/helloworld-java-maven'
         	sh "echo Build"
          mvnHome = tool 'rajesh-maven'
          sh "'${mvnHome}/bin/mvn' clean compile" 
        }
        stage('Deploy') 
	   {
         	sh "echo Deploy"
        }
        stage('Test') 
	   {
         	sh "echo Test"
          sh "'${mvnHome}/bin/mvn' clean test"
          junit '**/target/surefire-reports/TEST-*.xml'
        }
    }


node {
	   def mvnHome
        stage('Build') 
	   {
		git 'https://github.com/devopsschool-demo-labs-projects/helloworld-java-maven'
         	sh "echo Build"
          mvnHome = tool 'rajesh-maven'
          sh "'${mvnHome}/bin/mvn' clean compile" 
        }

        stage('Test') 
	   {
         	sh "echo Test"
          sh "'${mvnHome}/bin/mvn' clean test"
          junit '**/target/surefire-reports/TEST-*.xml'
        }
        stage('Deploy') 
	   {
         	sh "echo Deploying..."
		sh 'ansible-playbook -i inventory ansible-playbook.yaml'
        }
    }


node {
	   def mvnHome
        stage('Build') 
	   {
		git 'https://github.com/devopsschool-demo-labs-projects/helloworld-java-maven'
         	sh "echo Build"
          mvnHome = tool 'rajesh-maven'
          sh "'${mvnHome}/bin/mvn' clean compile" 
        }

        stage('Test') 
	   {
         	sh "echo Test"
          sh "'${mvnHome}/bin/mvn' clean test"
          junit '**/target/surefire-reports/TEST-*.xml'
        }

        stage('Package') 
	   {
         	sh "echo Package"
          sh "'${mvnHome}/bin/mvn' clean package"
		archive 'target/*.jar'
        }

        stage('Deploy') 
	   {
         	sh "echo Deploying..."
		sh 'ansible localhost -m setup'
        }
    }

loop.groovy

abcs = ['a', 'b', 'c']

node('master') {
    stage('Test 1: loop of echo statements') {
        echo_all(abcs)
    }
    stage('Test 2: loop of sh commands') {
        loop_of_sh(abcs)
    }
    stage('Test 3: loop with preceding SH') {
        loop_with_preceding_sh(abcs)
    }
    stage('Test 4: traditional for loop') {
        traditional_int_for_loop(abcs)
    }
}

@NonCPS // has to be NonCPS or the build breaks on the call to .each
def echo_all(list) {
    list.each { item ->
        echo "Hello ${item}"
    }
}
// outputs all items as expected

@NonCPS
def loop_of_sh(list) {
    list.each { item ->
        sh "echo Hello ${item}"
    }
}
// outputs only the first item

@NonCPS
def loop_with_preceding_sh(list) {
    sh "echo Going to echo a list"
    list.each { item ->
        sh "echo Hello ${item}"
    }
}
// outputs only the "Going to echo a list" bit

//No NonCPS required
def traditional_int_for_loop(list) {
    sh "echo Going to echo a list"
    for (int i = 0; i < list.size(); i++) {
        sh "echo Hello ${list[i]}"
    }
}
// echoes everything as expected

try.catch

How to apply try catch in jenkins scripted pipeline?
-------------------------------
node {
    stage('Example') {
        try {
            sh 'exit 1'
        }
        catch (exc) {
            echo 'Something failed, I should sound the klaxons!'
            throw
        }
    }
}

variable

How to define var in jenkins scripted pipeline?

# init a variable
def mvnHome

# set a value of it
mvnHome = tool 'maven'

# How to use
- ${mvnHome}
- sh "'${mvnHome}/bin/mvn' -Dmaven.test.failure.ignore clean compile"