Jenkins Declarative Pipeline: How to read choice from input step? - jenkins

Question

I'm trying to access a variable from an input step using the declarative pipelines syntax but it seems not to be available via env or params.
This is my stage definition:
stage('User Input') {
steps {
input message: 'User input required', ok: 'Release!',
parameters: [choice(name: 'RELEASE_SCOPE', choices: 'patch\nminor\nmajor', description: 'What is the release scope?')]
echo "env: ${env.RELEASE_SCOPE}"
echo "params: ${params.RELEASE_SCOPE}"
}
}
Both echo steps print null. I also tried to access the variable directly but I got the following error:
groovy.lang.MissingPropertyException: No such property: RELEASE_SCOPE for class: groovy.lang.Binding
at groovy.lang.Binding.getVariable(Binding.java:63)
at org.jenkinsci.plugins.scriptsecurity.sandbox.groovy.SandboxInterceptor.onGetProperty(SandboxInterceptor.java:224)
What is the correct way to access this choice parameter?

Answer 1

Since you are using declarative pipelines we will need to do some tricks. Normally you save the return value from the input stage, like this
def returnValue = input message: 'Need some input', parameters: [string(defaultValue: '', description: '', name: 'Give me a value')]
However this is not allowed directly in declarative pipeline steps. Instead, what you need to do is wrap the input step in a script step and then propagate the value into approprierte place (env seems to work good, beware that the variable is exposed to the rest of the pipeline though).
pipeline {
agent any
stages {
stage("foo") {
steps {
script {
env.RELEASE_SCOPE = input message: 'User input required', ok: 'Release!',
parameters: [choice(name: 'RELEASE_SCOPE', choices: 'patch\nminor\nmajor', description: 'What is the release scope?')]
}
echo "${env.RELEASE_SCOPE}"
}
}
}
}
Note that if you have multiple parameters in the input step, then input will return a map and you need to use map references to get the entry that you want. From the snippet generator in Jenkins:
If just one parameter is listed, its value will become the value of the input step. If multiple parameters are listed, the return value will be a map keyed by the parameter names. If parameters are not requested, the step returns nothing if approved.

Answer 2

Using the Input Step in the following form works for multiparameters:
script {
def params = input message: 'Message',
parameters: [choice(name: 'param1', choices: ['1', '2', '3', '4', '5'],description: 'description'),
booleanParam(name: 'param2', defaultValue: true, description: 'description')]
echo params['param1']
echo params['param2']
}

Answer 3

#DavidParker, I have figured out what you are asking. Just try to use it in your code. I have input params and using them 1 by 1. I am printing only "variable" key in job which is working. You can also try this way.
steps{
script {
deploymentParams.findAll{ key, value -> key.startsWith('backendIP') }.each { entry ->
stage("Node_$entry.key "){
echo $entry.value
}
}
}
}