Jenkins pipeline with parallel - jenkins

Question

Here is my Jenkins pipeline that i am trying to execute. I am following this tutorial:
pipeline {
agent any
stages {
stage('one') {
parallel "first" : {
echo "hello"
},
"second": {
echo "world"
}
}
stage('two') {
parallel "first" : {
echo "hello"
},
"second": {
echo "world"
}
}
}
}
But the job fails with following message.
org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
WorkflowScript: 4: Unknown stage section "parallel". Starting with version 0.5, steps in a stage must be in a steps block. # line 4, column 9.
stage('one') {
^
WorkflowScript: 12: Unknown stage section "parallel". Starting with version 0.5, steps in a stage must be in a steps block. # line 12, column 9.
stage('two') {
^
WorkflowScript: 4: Nothing to execute within stage "one" # line 4, column 9.
stage('one') {
^
WorkflowScript: 12: Nothing to execute within stage "two" # line 12, column 9.
stage('two') {
^
4 errors
Can someone please help me out why this is failing.

Answer 1

You need to add a steps block after your stage declaration.
pipeline {
agent any
stages {
stage('Example Stage 1') {
steps {
parallel(
"step 1": { echo "hello" },
"step 2": { echo "world" },
"step 3": { echo "world" }
)
}
}
stage('Example Stage 2') {
steps {
parallel(
"step 1": { echo "hello" },
"step 2": { echo "world" },
"step 3": { echo "world" }
)
}
}
}
}
To Make your Stages Parallel use this, both solutions show up very similar in Blue Ocean :
pipeline {
agent any
stages {
stage('Example Stage') {
parallel {
stage('Stage 1') {
steps { sh 'echo stage 1 passed' }
}
stage('Stage 2') {
steps { sh 'echo stage 2 passed' }
}
stage('Stage 3') {
steps { sh 'echo stage 3 passed' }
}
}
}
}
}

Answer 2

You need to upgrade the Declarative Pipeline plugin on your Jenkins to Version 1.2 (Sept 21, 2017) or above

Answer 3

In declarative pipeline, in case if you want to add stage, inside steps, this nesting is also possible.
If the steps are same in that case you can declare step as a function.
def steps = ['first', 'second']
def generateSteps(stepLabel) {
return {
step("${stepLabel}") {
echo "Running on ${stepLabel}"
}
}
}
def parallelStepMap = steps.collectEntries {
["${it}" : generateSteps(it)]
}
pipeline {
agent any
stages {
stage('non-parallel stage') {
steps {
echo 'This stage will be executed first.'
}
}
stage('parallel stage') {
steps {
script {
parallel parallelStepMap
}
}
}
}
}
General need is to execute different stages into different nodes.
in such case above function can be modified to execute on different agent nodes as follows.
def agents = ['master', 'agent1', 'agent2']
def generateStage(nodeLabel) {
return {
stage("Runs on ${nodeLabel}") {
node(nodeLabel) {
echo "Running on ${nodeLabel}"
}
}
}
}
def parallelStagesMap = agents.collectEntries {
["${it}" : generateStage(it)]
}
pipeline {
agent none
stages {
stage('non-parallel stage') {
steps {
echo 'This stage will be executed first.'
}
}
stage('parallel stage') {
steps {
script {
parallel parallelStagesMap
}
}
}
}
}
With nodelabel defined inside the function and agent none during start of pipeline, the stages will be executed into different nodes.