This week, we released the second beta of the newDeclarative Pipeline syntax, available in the Update Center now as version 0.8.1 of Pipeline: Model Definition. You can read more about Declarative Pipelinein the blog post introducing the first beta from December, but we wanted to update you all on the syntax changes in the second beta. These syntax changes are the last compatibility-breaking changes to the syntax before the 1.0 release planned for February, so you can safely start using the 0.8.1 syntax now without needing to change it when 1.0 is released.
A full syntax reference is available on the wiki as well.
Syntax Changes
Changed "agent" configuration to block structure
In order to support more detailed and clear configuration of agents, as well as
making agent syntax more consistent with the rest of the Declarative Pipeline
syntax, we’ve moved the agent configuration into blocks. The agent any andagent none configurations work the same as previously, but label, docker
and dockerfile now look like the following:
Just specifying a label is simple.
agent {
label "some-label"
}If you’re just specifying a Docker image, you can use this simple syntax.
agent {
docker "ubuntu:16.04"
}When you are specifying a label or other arguments, docker looks like this:
agent {
docker {
image "ubuntu:16.04"
label "docker-label"
args "-v /tmp:/tmp -p 8000:8000"
}
}When you’re building an image from "Dockerfile" in your repository and don’t care what node is used or have additional arguments, you can again use a simple syntax.
agent {
dockerfile true
}When you’re building an image from a different file, or have a label or other arguments, use the following syntax:
agent {
dockerfile {
filename "OtherDockerfile"
label "docker-label"
args "-v /tmp:/tmp -p 8000:8000"
}
}Improved "when" conditions
We introduced the when section a couple releases ago, but have made some
changes to its syntax here in 0.8.1. We wanted to add some simpler ways to
specify common conditions, and that required we re-work the syntax accordingly.
Branch
One of the most common conditions is running a stage only if you’re on a specific branch. You can also use wildcards like "*/master".
when {
branch "master"
}"options" replaces "properties" and "wrappers"
We’ve renamed the properties section to options, due to needing to add new
Declarative-specific options and to cut down on confusion. The options section
is now where you’ll put general Pipeline options like buildDiscarder,
Declarative-specific options like skipDefaultCheckout, and block-scoped steps
that should wrap the execution of the entire build, like timeout ortimestamps.
options {
buildDiscarder(logRotator(numToKeepStr:'1'))
skipDefaultCheckout()
timeout(time: 5, unit: 'MINUTES')
}Heading towards 1.0!
While we may still add more functionality to the Declarative Pipeline syntax, we won’t be making any changes to existing syntax for the 1.0 release. This means that any pipelines you write against the 0.8.1 syntax will keep working for the foreseeable future without any changes. So if you’re already using Declarative Pipelines, make sure to update your `Jenkinsfile`s after upgrading to 0.8.1, and if you haven’t been using Declarative Pipelines yet, install the Pipeline: Model Definition plugin and give them a try!