OpenShift Pipelines give you control over building, deploying, and promoting your applications on OpenShift. Using a combination of the Jenkins Pipeline Build Strategy, Jenkinsfiles, and the OpenShift Domain Specific Language (DSL) (provided by the OpenShift Jenkins Client Plug-in), you can create advanced build, test, deploy, and promote pipelines for any scenario.
The OpenShift Jenkins Client Plug-in must be installed on your Jenkins master so the OpenShift DSL will be available to use within the JenkinsFile for your application. This plug-in is installed and enabled by default when using the OpenShift Jenkins image.
The OpenShift Jenkins Client Plug-in provides a fluent-styled DSL for communicating with the OpenShift API from within the Jenkins slaves. The OpenShift DSL is based on Groovy syntax and provides methods for controlling the lifecycle of your application such as create, build, deploy, and delete.
The full details of the API are embedded within the plug-in’s online documentation within a running Jenkins instance. To find it:
Create a new Pipeline Item.
Click Pipeline Syntax below the DSL text area.
From the left navigation menu, click Global Variables Reference.
In order to take advantage of the OpenShift Pipelines within your project, you
will must use the
Pipeline Build Strategy. This strategy defaults to using a
jenkinsfile at the
root of your source repository, but also provides the following configuration
jenkinsfile field within your BuildConfig.
jenkinsfilePath field within your BuildConfig that references the location
jenkinsfile to use relative to the source
For more detailed information about the Jenkins Pipeline Strategy, see Pipeline Strategy Options.
jenkinsfile utilizes the standard groovy language syntax to allow fine
grained control over the configuration, build, and deployment of your
jenkinsfile can be supplied in one of the following ways:
A file located within your source code repository.
Embedded as part of your build configuration using the
When using the first option, the
jenkinsfile must be included in your
applications source code repository at one of the following locations:
A file named
jenkinsfile at the root of your repository.
A file named
jenkinsfile at the root of the source
contextDir of your
A file name specified via the
jenkinsfilePath field of the
JenkinsPiplineStrategy section of your BuildConfig, which is relative to the
contextDir if supplied, otherwise it defaults to the root of the
jenkinsfile is executed on the Jenkins slave pod, which must have the
OpenShift Client binaries available if you intend to use the OpenShift DSL.
For a full walkthrough of building and deploying an application with Jenkins Pipeline, see Jenkins Pipeline Tutorial.
When a Pipeline build configuration is created, OpenShift checks to see if there is currently a Jenkins master pod provisioned in the current project. If no Jenkins master is found, one is automatically created. If this behavior is not desirable, or if you would like to use a Jenkins server external to OpenShift, you can disable it.
The Kubernetes Plug-in is also pre-installed in the official Jenkins image. This plug-in allows the Jenkins master to create slave pods on OpenShift and delegate running jobs to them to achieve scalability as well as providing pods with specific runtimes for specific jobs.
For more detailed information on configuring slave pods using the Kubernetes Plug-in, see Kubernetes Plug-in.