Is it possible to include calls in Declarative Pipelines in the shared library (Jenkins)? - jenkins

Question

As you know in shared libraries in Jenkins, it is possible to call in the Jenkinsfile a content of a file in vars folder.
For example in vars folder in the shared library we can have a file named build.groovy and in the Jenkinsfile we can call it by :
build {
parameter1 = "some param1"
parameter2 = "some param2"
}
As it is described in this section .
I have no problems having groovy files and calling them with call() method in Jenkinsfile.
But I want to customize a pipeline and make it as generic as possible.
So I want to call a groovy file contained in vars folder but in the same pipeline : Calling a genericStage.groovy in an other file contained in the same vars folder in the shared library.
So what I have is a groovy file in vars folder : genericStage.groovy
What I have is :
Pipeline{
agent{label myNode}
stages{
stage("init"){
//steps
}
genericStage{
parameter1 = "some param"
}
}
}
And in the genericStage :
def call(Closure body) {
def config = [:]
body.resolveStrategy = Closure.DELEGATE_FIRST
body.delegate = config
body()
stage(config.parameter1){
steps{
//steps
}
}
}
But I get the error :
Expected a stage # line 125, column 6.
genericStage{
^
1 error
at org.codehaus.groovy.control.ErrorCollector.failIfErrors(ErrorCollector.java:310)
at org.codehaus.groovy.control.CompilationUnit.applyToPrimaryClassNodes(CompilationUnit.java:1085)
So how to make calls in the same shared library as we do for the Jenkinsfile ?

Answer 1

In your shared library method defining a DSL style step like this you can either define a block of steps and script that does some common processing you need to share between jobs or stages in a job or a whole complete pipeline. So your genericStage.groovy can only contain what comes after the "// steps" comment and cannot contain the stage and steps definition like this. I do this type of library custom step quite a lot in the style you have here but without trying to define the stage / steps inside it and it works fine. What is happening for you here is the pipeline validation / parser is failing the main pipeline syntax before it even gets to handling your custom step because you don't have it wrapped in a stage and steps definition.
If you read the documentation link you have at the end there is a section on defining a complete declarative pipeline in a shared library. It says at the end "Only entire pipelines can be defined in shared libraries as of this time. This can only be done invars/*.groovy, and only in a call method. Only one Declarative Pipeline can be executed in a single build, and if you attempt to execute a second one, your build will fail as a result." This suggests that a partial pipeline like you have won't work, you should have just steps / script or a complete pipeline.