The presentation by Alan Beale at the Jenkins User Conference discusses the use of Job DSL and System Groovy for automating bulk updates in Jenkins job configurations. It highlights how Job DSL can streamline job creation with a Groovy language, while System Groovy scripts can automate repetitive tasks efficiently. The talk concludes with insights on creating a parameterized job generator and the significance of structured variations in jobs.

1. Jenkins User Conference San Francisco #jenkinsconf
Supercharged Configuration As Code
Bulk Updates with Job DSL and System Groovy
Alan Beale
Chicago Trading Company
!
!
October 23, 2014
#jenkinsconf

2. Jenkins User Conference San Francisco #jenkinsconf
Who Am I
• Alan Beale
Build Engineer @ Chicago Trading Company
The statements, remarks and conclusions of this
presentation are my own and do not represent the views
of my employer, CTC Trading Group, L.L.C. (“CTC”).

3. Jenkins User Conference San Francisco #jenkinsconf
Have you ever found a
change that you need to
apply to 100 jobs?

4. Jenkins User Conference San Francisco #jenkinsconf
• Job DSL is a plugin that allows users to create job
configurations with a groovy domain specific
language
• System groovy scripts are groovy scripts that have
access the the Jenkins.instance calling various parts
of the Jenkins API

5. Jenkins User Conference San Francisco #jenkinsconf
Observations about build jobs
• Jobs Change over Time
• Most jobs are like other jobs

6. Jenkins User Conference San Francisco #jenkinsconf
Jobs Change Over Time
• Correctness Changes
• Bug Fixes
• Complexity Increase

7. Jenkins User Conference San Francisco #jenkinsconf
Most Jobs are Similar
• Small number of themes with structured variation

8. Jenkins User Conference San Francisco #jenkinsconf
Example of Job Themes
• Continuous Integration Jobs
• Gerrit Verification Jobs
• Release Jobs
• Privileged SCM Task Automation

9. Jenkins User Conference San Francisco #jenkinsconf
How do these observations help?
• Job DSL enables us to using coding techniques to
create job configurations
• System groovy scripts enable use to automate
repeated calls to jobs

10. Jenkins User Conference San Francisco #jenkinsconf
Player Piano
• Our metaphor for bulk job regeneration

11. Jenkins User Conference San Francisco #jenkinsconf
The Piano Roll
• Controls the sound of the piano
• Orchestrates the automation of job recreation

12. Jenkins User Conference San Francisco #jenkinsconf
Job DSL for gradle build
job {
name "git-gradle-simple-build"
scm {
git('/Users/alanbeale/sandbox/samples/java/basic',
'*/master' )
}
steps {
gradle ( "build", null, true )
}
}

13. Jenkins User Conference San Francisco #jenkinsconf
Evolution Example
job {
name "git-gradle-build-with-worspace-option"
scm {
git('/Users/alanbeale/sandbox/samples/java/basic',
‘*/master')
}
steps {
gradle ( "build", null, true
){ node -> //hudson.plugins.gradle.Gradle
node/useWorkspaceAsHome(true)
}
}
}

14. Jenkins User Conference San Francisco #jenkinsconf
Add Gerrit Trigger
• https://github.com/bealeaj1214/jenkins-juc-
job-dsl-bulk-regeneration/blob/master/src/
examples/jobdsl/scm-gradle-gerrit-build.jobDSL

15. Jenkins User Conference San Francisco #jenkinsconf
Repeated elements
• Job Name
• Git URL
• Gerrit Trigger Project

16. Jenkins User Conference San Francisco #jenkinsconf
Towards Job Factory
• Factor out common operations
• Parameterize calling Job DSL

17. Jenkins User Conference San Francisco #jenkinsconf
Create Utility class
• jobdsl.JobUtilities methods
• setupGradleGerritJobName()
• setupGerritScm()
• setupGerritTrigger()
• setupGradleBuild()

18. Jenkins User Conference San Francisco #jenkinsconf
JobUtilities.groovy
• https://github.com/bealeaj1214/jenkins-juc-
job-dsl-bulk-regeneration/blob/master/src/
main/groovy/jobdsl/JobUtilities.groovy

19. Jenkins User Conference San Francisco #jenkinsconf
generator job DSL
• https://github.com/bealeaj1214/jenkins-juc-
job-dsl-bulk-regeneration/blob/master/src/
generator/jobdsl/
seed4GradleGerritJobs.jobDSL

20. Jenkins User Conference San Francisco #jenkinsconf
Part 2 : System Groovy

21. Jenkins User Conference San Francisco #jenkinsconf
Regeneration script
import jenkins.model.*
!
import hudson.model.*
!
def jenkins = jenkins.model.Jenkins.instance
def jobGeneratorName='gradle-gerrit-job-generator'
def jobGenerator = jenkins.getItem(jobGeneratorName)
def projectParamName ='PROJECT_NAME'
def projectParamValue=‘sample/java/library'
!
if(jobGenerator){
boolean buildQueued =
jobGenerator.scheduleBuild( 5,
new Cause.UserIdCause(),
new ParametersAction(
new StringParameterValue(projectParamName, projectParamValue)
)
)
}

22. Jenkins User Conference San Francisco #jenkinsconf
Regenerate from existing job name
import jenkins.model.*
!
import hudson.model.*
!
def jenkins = jenkins.model.Jenkins.instance
def jobGeneratorName='gradle-gerrit-job-generator'
def jobGenerator = jenkins.getItem(jobGeneratorName)
def projectParamName ='PROJECT_NAME'
def jobs = jenkins.getItems()
!
def gerritJobs = jobs.findAll { job ->
job.name.endsWith('gradle-gerrit')
}
!
def projectNames =gerritJobs.collect { item ->
item.triggers.values().find {
it.class.simpleName =='GerritTrigger'
}. gerritProjects[0].pattern
}
!
if(jobGenerator){
projectNames.each { projectName ->
boolean buildQueued =
jobGenerator.scheduleBuild( 5,
new Cause.UserIdCause(),
new ParametersAction(
new StringParameterValue( projectParamName,projectName)
)
)
}
}

23. Jenkins User Conference San Francisco #jenkinsconf
Summary
• Job DSL enables precise control
• Define parameterized Job Generator (the piano)

24. Jenkins User Conference San Francisco #jenkinsconf
Summary
• System Groovy Jobs
• automates calling job generator in bulk
(piano roll)

25. Jenkins User Conference San Francisco #jenkinsconf
Thank You To Our Sponsors
Platinum Gold
Silver
Corporate

26. Jenkins User Conference San Francisco #jenkinsconf
Thank You
• Source Code at https://github.com/bealeaj1214/
jenkins-juc-job-dsl-bulk-regeneration