cje-prep/09-rest-api.md

Key CI/CD/Jenkins Concepts and their Usage

Using the REST API for common operations

1. Create a new user named buildbot.
2. Add adminstration permissions for the user.
3. Log in with user buildbot.
4. Generate the API token for the user.
5. Generate a Jenkins crumb from the command line.
6. Export the environment variables JENKINS_CRUMB and JENKINS_API_TOKEN with the correct values.
7. Trigger a build of the job gradle-initializr with a curl command using the REST API.
8. Disable the job gradle-initializr with a curl command using the REST API.
9. Reenable the job gradle-initializr with a curl command using the REST API.
10. Download the Jenkins CLI client.
11. Trigger the build of the job gradle-initializr with a curl command using the Jenkins CLI.

Show Solution

Create the new user.

Add user permissions.

Generate the API token.

Generate the Jenkins crumb from the CLI.

$ curl -u "buildbot:pwd" 'http://localhost:8080/crumbIssuer/api/xml?xpath=concat(//crumbRequestField,":",//crumb)'
Jenkins-Crumb:890d0b4c9c1b111deb55b196813a0ae1
$ export JENKINS_CRUMB=Jenkins-Crumb:890d0b4c9c1b111deb55b196813a0ae1
$ export JENKINS_API_TOKEN=11e2f3c68399b6bc3a28bc06e002be104d

Trigger a build with the curl command.

$ curl -X POST -H "$JENKINS_CRUMB" http://buildbot:$JENKINS_API_TOKEN@localhost:8080/job/gradle-initializr/build

Disable the job via the REST API. You will see that the job indicated its status.

$ curl -X POST -H "$JENKINS_CRUMB" http://buildbot:$JENKINS_API_TOKEN@localhost:8080/job/gradle-initializr/disable

Reenable the job.

$ curl -X POST -H "$JENKINS_CRUMB" http://buildbot:$JENKINS_API_TOKEN@localhost:8080/job/gradle-initializr/enable

Download the Jenkins URL by calling the URL localhost:8080/jnlpJars/jenkins-cli.jar from the browser.

In the terminal, navigate to the directory that contains the Jenkins CLI JAR file. Use the Jenkins CLI to trigger a build with the correct command. This simply provide the password instead of the API token.

$ java -jar jenkins-cli.jar -s http://localhost:8080 -auth buildbot:pwd build gradle-initializr