Jenkinsfile Crib Sheet

In this guide we are working only with Scripted Pipelines, not Declarative Pipelines.

Nodes

node {

}

This is used to schedule the steps held within on the next available executor, it is possible to customise this to specify an executor (such as a windows one).

Properties

properties([
            [$class: 'BuildDiscarderProperty', strategy: [$class: 'LogRotator', artifactDaysToKeepStr: '', artifactNumToKeepStr: '', daysToKeepStr: '', numToKeepStr: '5']],
            parameters([
                    choice(choices: ['ode-1','ode-2','uat', 'stg', 'prd-1', 'prd-2'], description: 'Environment', name: 'envName'),
                    string(defaultValue: "master", description: 'What costa-web branch? - Ignore origin/', name: 'webBranch')
            ])
])

Build Description

 currentBuild.description = "Set some text here e.g. branch name etc."

Jenkins Current Build Description

Stage

stage('do some stuff') {

}

This wraps the steps within a named stage e.g.:

Jenkins Stages

Pull SCM

stage('Pull') {
    checkout scm
}

Clean up workspace

stage('Clear Workspace') {
   step([$class: 'WsCleanup'])
}

Try/Catch & Build Status Notifications

node {
    try {
        stage ('build') {
            sh './configure && make'
        }
        
    } catch (e) {
          // If there was an exception thrown, the build failed
          currentBuild.result = "Jenkins Job Failed"
          //use slack plugin (https://github.com/jenkinsci/slack-plugin)
          slackSend color: '#FF0000', message: 'This broke'
          // Microsoft Teams
          office365ConnectorSend message: msg, status: buildStatus, webhookUrl: "${web_hook_url}", notifyBackToNormal: true, notifyFailure: true, notifyRepeatedFailure: true, notifySuccess: false, notifyUnstable: true, startNotification: false
          // Or CURL
          sh 'curl https://webhook.slack.com ...'
          throw e

    } finally {
        // stuff that should happen no matter what
        
    }
}

Using Credentials

stage('do something with credentials') {
     withCredentials([string(credentialsId: 'some-webook-url', variable: 'web_hook_url')]) {
        sh "curl $web_hook_url"
     }
}

Building containers

stage('Build Container') {
    container = docker.build("${image_name}", ".")
}

Using a docker regsitry

stage('Push Image to AWS ECR') {
    docker.withRegistry('https://012345abcdef.dkr.ecr.eu-west-1.amazonaws.com') {
        sh "eval \$(aws ecr get-login --no-include-email)"
        docker.image("${image_name}").push()
    }
}

Here we assume that there is an IAM profile attached to the Jenkins instance and that it has the appropriate properties set or that there is a profile using keys available to the Jenkins user.

Building inside containers

stage('build the app') {
    docker.images('node:8.10-alpine').inside('-u root') {
        // Do the same steps but inside the container
        sh 'whoami'
    }
}

Example of setting the user (don’t set to root)
This mounts the current workspace inside the container
If you were to modify files as root inside the container this may mean that jenkins outside the container doesn’t have the right permissions to modify the files in the workspace.

Bin/Bash

stage('some bash thing') {
    sh "/bin/bash myBashScript.sh"
}

You can specify the shell to be used (this isn’t usually necessary but may help in certain scenarios).

Get bash output

GIT_SHA = sh(returnStdout: true, script: 'git rev-parse HEAD').trim()

Trigger another job

build job: 'deploy-application', parameters: [string(name: 'AWS_ENV', value: "dev")], wait: false

Disable concurrent builds

node {
    properties([disableConcurrentBuilds()])
}

Schedule Build via Cron

node {
    properties([pipelineTriggers([cron("*/10 * * * *")])])
}

Colour Terminal Output

wrap([$class: 'AnsiColorBuildWrapper', colorMapName: "xterm"]) {
    sh 'jest --config jest.integration.config.js --colors'
}