The exact list of plugins for enabling Docker commands within Jenkins jobs is somewhat unclear.
Looks like at least the Docker Build Step plugin is required to make this happen.
This does two things:
- Helps us to run
dockercommands within Execute Shell steps - Adds the "Execute Docker Command" build step .
Important Configuration
-
Make sure the Jenkins user is added to the
dockergroup. eg.usermod -aG docker jenkins. If you don't do this, you might see errors likeGot permission denied while trying to connect to the Docker daemon socket. -
Make sure to restart the machine as well as Jenkins Service for the above user change to take effect.
**Question: ** The Jenkins Pipeline Job Type has the "Poll SCM" field. But if I use multiple SCMs, does this work, and if so how?
**Answer: **
It does work across multiple SCMs. Suppose you have the following setup:
- App code stored in one repo
- Deployment Ansible Playbooks stored in another repo
- Jenkins Pipeline code which builds the app and deploys it is stored in a third repo.
In this case, "Poll SCM" will work across all 3 repos above. It will poll all the repos as per the schedule you specify. And changes to any repo will trigger the pipeline.
(This conforms to the Continuous Delivery idea that any change should trigger the pipeline.)
This error took me a day and a half to figure out.
- A Pipeline Job is configured to pick the code from SCM.
- There is a
Jenkinsfile, which loads methods (def methodName) from ajob-config.groovyfile.
Everything was working well until I decided to add a stub method to invoke an ansible playbook.
def invokePlaybook() {
}
Using the Snippet Generator functionality, I generated some sample pipeline code as follows:
The generated code looked like this:
But when I copied the code, I chose to insert some newline characters.
def invokePlaybook() {
ansiblePlaybook
credentialsId: 'jenkins-gitlab-ssh-key',
extras: '--extra-vars @extra_vars.json',
installation: 'Ansible-2.3.0',
inventory: 'inventories/sit/',
playbook: 'playbook.yml',
sudo: true, sudoUser: "root"
}
So what was the cause?
Either the multiple-line entry was the cause, or perhaps it was the use of the @extra_vars.json? Who knows?
What I did find, however, was that if I paste the code in the inline-groovy editor (Job Type: Pipeline Script) it throws a compilation error. So remember to do this when writing your pipeline code!
org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
WorkflowScript: 112: unexpected token: jenkins-gitlab-ssh-key @ line 112, column 20.
credentialsId: 'jenkins-gitlab-ssh-key',
This plugin installs several useful functionalities exposed via Pipeline Steps.
E.g:
readJSON: Read JSON from files in the workspace.
readMavenPom: Read a maven project pom.xml file.
