Resources

• GitHub - jenkinsci/docker - Official Jenkins Docker image (opens in a new tab)
• Jenkins Core - Java API (opens in a new tab)

Cheatsheet

Create credentials programatically

• Stack Overflow - automation - Automate Setting Jenkins Credentials and Global Variables (opens in a new tab)

HTTP API

Specific Job API

$JENKINS_URL/<Job>/api

Specific Pipeline API

$JENKINS_URL/<Pipeline>/api

View Configuration as Code of Jenkins instance

$JENKINS_URL/manage/configuration-as-code/viewExport

JSON Schema

$JENKINS_URL/manage/configuration-as-code/schema

Job

• Job types

  • Freestyle project

  • Pipeline

  • Multibranch Pipeline

• Job DSL can be used to create Jobs such as Pipelines.

Job DSL

• API Reference

  • Any Jenkins instance

    • $JENKINS_URL/plugin/job-dsl/api-viewer/index.html

  • Managed version on internet

    • Jenkins Job DSL API (opens in a new tab)

• Resources

  • GitHub - jenkinsci/job-dsl-plugin (opens in a new tab)

CLI

Jenkins CLI

$JENKINS_URL/jnlpJars/jenkins-cli.jar

Plugin Installation Manager Tool

• In official Docker image, /bin/jenkins-plugin-cli will invoke jar located at /opt/jenkins-plugin-manager.jar

• Resources

  • GitHub - jenkinsci/plugin-installation-manager-tool - Plugin Installation Manager Tool for Jenkins (opens in a new tab)

Configuration as Code

• Resources

  • GitHub - jenkinsci/configuration-as-code-plugin (opens in a new tab)
  • Jenkins Configuration as Code (opens in a new tab)
  • Jenkins Plugins - Configuration as Code (opens in a new tab)

Pipeline

• Presence of the Jenkinsfile in the root of a repository makes it eligible for Jenkins to automatically manage and execute jobs based on repository branches.

• The Jenkinsfile should contain a Pipeline script, specifying the steps to execute the job.

• Resources

  • Pipeline Syntax (opens in a new tab)
  • Pipeline Steps Reference (opens in a new tab)
  • User Handbook - Pipeline as Code (opens in a new tab)

Shared Library

• One var script can only invoke other var scripts without approval.

• Resources

  • Jenkins Usesr Handbook - Extending with Shared Libraries (opens in a new tab)
  • Share a standard Pipeline across multiple projects with Shared Libraries (opens in a new tab)
  • Setting up a shared library and seed job in Jenkins - Part 1 (opens in a new tab)
  • Setting up a shared library and seed job in Jenkins - Part 2 (opens in a new tab)

Pipeline Snippet Generator

$JENKINS_URL/pipeline-syntax

Directive Generator

$JENKINS_URL/directive-generator

Steps Reference

$JENKINS_URL/pipeline-syntax/html

Global Variables Reference

$JENKINS_URL/pipeline-syntax/globals

Debugg Pipeline as Code

• Use Replay to make ad-hoc edits to Pipeline code, and run the Pipeline, repeat until done, copy the code to VCS for future deployments.

Multibranch Pipeline

• Jenkins automatically discovers, manages, and executes jobs for multiple source repositories and branches.

• A multi-branch pipeline project always includes a Jenkinsfile in its repository root. Jenkins automatically creates a sub-project for each branch that it finds in a repository with a Jenkinsfile.

• Resources

  • GitHub - jenkinsci/workflow-multibranch-plugin (opens in a new tab)

Jenkins Templating Engine

• Jenkins Templating Engine (opens in a new tab)

Tips

Retrieve Job configuration XML

• Declarative Pipeline upon execution are converted to configuration in XML format.
• To retrieve the config after conversion, use $JENKINS_URL/job/<job-name>/config.xml

Convert Job DSL to configuration XML

• Use Job DSL Playground (opens in a new tab) to check output of the Job DSL.

Use Job configuration XML to guide authoring Job DSL

• On Jenkins UI, create a Job and save config changes.

• Get XML of the Job configuration

  Using <JENKINS_URL>/../<JOB_name>/config.xml

• Get XML of your Job DSL

  Using Job DSL Playground

• Compare both XML config to check the difference

  Declarative Pipelines are structured similar to XML configurations.

• Use configure function in Job DSL

  • Jenkins Job DSL Plugin - configure (opens in a new tab)

• Try plugin XML Job to Job DSL

  • Jenkins plugin - XML Job to Job DSL (opens in a new tab)

    Note: Many plugins not supported

• Resources

  • Jenkins xml configuration to Groovy-based Jenkins Job DSL - Stack Overflow (opens in a new tab)

Caveats

• Pipeline script from SCM

  • GitLab Personal Access Token is not supported as credentials