Run stages in multiple nodes - jenkins

I have a declarative pipeline.
In this pipeline I want various stages not executed by only one but multiple nodes (later stages, which are node specific, depend on these). Is this somehow possible?

sure, you can select different nodes in different stages based on label:
pipeline {
agent none
stages {
stage('build') {
steps {
node('docker') {
sh 'echo $HOSTNAME'
}
}
}
stage('test') {
steps {
node('rbenv') {
sh 'echo $HOSTNAME'
}
}
}
}
}
does that make sense?

You can follow the following format in your pipeline job to perform specific tasks on specific nodes:
node('master') {
.....................
<some task to perform>
.....................
}
node('slave1 && slave2') {
.....................
<some task to perform>
.....................
}

Related

Running script (stash) prior to parallel stages being invoked

I have a parallel stage setup, and would like to know if it's possible to run a script prior to the nested stages, so something like this:
stage('E2E-PR-CYPRESS') {
when {
allOf {
expression {
return fileExists("cypress.json")
}
branch "PR-*"
}
}
steps {
script {
stash name: 'cypress-dir', includes: 'cypress/**/*'
}
}
parallel {
stage('Cypress Tests 1') {
agent { label 'aws_micro_slave_e2e' }
options { skipDefaultCheckout() }
steps {
runE2eTests()
}
}
stage('Cypress Tests 2') {
agent { label 'aws_micro_slave_e2e' }
options { skipDefaultCheckout() }
steps {
runE2eTests()
}
}
}
post {
always {
e2eAfterCypressRun(this, true)
}
}
}
I know the above is wrong, I get the error Only one of "matrix", "parallel", "stages", or "steps" allowed for stage "E2E-PR-CYPRESS"
I already have the stash script in a setup stage at the beginning of my pipeline, but I'd like to be able to restart from this stage above on Jenkins, and so need the stash part in this stage as the parallel stages need to unstash the contents.
Updated Answer:
After playing a bit with the Restart from a Stage option there is seems to be a nice feature designed exactly for your needs called Preserving stashes for Use with Restarted Stages:
Normally, when you run the stash step in your Pipeline, the resulting
stash of artifacts is cleared when the Pipeline completes, regardless
of the result of the Pipeline. Since stash artifacts aren’t accessible
outside of the Pipeline run that created them, this has not created
any limitations on usage. But with Declarative stage restarting, you
may want to be able to unstash artifacts from a stage which ran before
the stage you’re restarting from.
To enable this, there is a job property that allows you to configure a
maximum number of completed runs whose stash artifacts should be
preserved for reuse in a restarted run. You can specify anywhere from
1 to 50 as the number of runs to preserve.
This job property can be configured in your Declarative Pipeline’s options section, as below:
options {
preserveStashes()
// or
preserveStashes(buildCount: 5)
}
This built in feature is exactly what you need to solve your issue without any special modifications to your code, as it will allow you to rerun the pipeline from any stage and still use the existing file that were previously stashed.
Original Answer:
You can actually achieve this quite simply using the scripted syntax for the parallel command, and it will also allow you to avoid the duplicate code in the parallel stages.
parallel: Execute in parallel
Takes a map from branch names to closures and an optional argument failFast which will terminate all branches upon a failure in any other branch:
parallel firstBranch: {
// do something
}, secondBranch: {
// do something else
},
failFast: true|false
In your case it can look like:
stage('E2E-PR-CYPRESS') {
when {
allOf {
expression {
return fileExists("cypress.json")
}
branch "PR-*"
}
}
steps {
script {
stash name: 'cypress-dir', includes: 'cypress/**/*'
// Define the parallel execution stages
def stages = ['Cypress Tests 1', 'Cypress Tests 2']
// Create the parallel executions and run them
parallel stages.collectEntries {
["Running ${it}": {
node('aws_micro_slave_e2e') {
skipDefaultCheckout()
runE2eTests()
}
}]
}
}
}
post {
always {
e2eAfterCypressRun(this, true)
}
}
}
This way you can easily add more parallel steps by updating the stages list, or even receive it as an input parameter. In addition you can create the parallel executions by different labels or tests suits, instead of the stage name.
You can add a Prepare stage at the top like this:
stages{
stage('Preperation'){
when {
allOf {
expression {
return fileExists("cypress.json")
}
branch "PR-*"
}
}
steps {
script {
stash name: 'cypress-dir', includes: 'cypress/**/*'
}
}
}
stage('E2E-PR-CYPRESS') {
parallel {
stage('Cypress Tests 1') {
agent { label 'aws_micro_slave_e2e' }
options { skipDefaultCheckout() }
steps {
runE2eTests()
}
}
stage('Cypress Tests 2') {
agent { label 'aws_micro_slave_e2e' }
options { skipDefaultCheckout() }
steps {
runE2eTests()
}
}
}
}
}
post {
always {
e2eAfterCypressRun(this, true)
}
}
An out of the box concept
Propose splitting the job into 2 parts taking the following into consideration:
Currently use an EC2 plugin, as the current agents are EC2
Running the parallel stages with the same stashed content ready to unstash
Create jenkins pipeline job 1:
This job will checkout the workspace with any type of agent
Create a packer json to create a customised AMI for the EC2
The customised AMI will stash the contents and move to a directory that will appear on the EC2 when the agent is built
Output the AMI ID, run a groovy job to update the EC2 plugin AMI ID with the customised AMI ID to temporarily set the AMI in memory on Jenkins
pipeline {
agent {
docker {
test-container
}
}
options {
buildDiscarder(
logRotator(
numToKeepStr: '10',
artifactNumToKeepStr: '10'
)
)
ansiColor('xterm')
gitConnection("git")
}
stages {
stage('Run Stash Cypress Functional Test') {
steps {
dir('functional-test') {
// develop branch is canary build, all other branches are stable builds
script {
sh """
# script to stash cypress tests
"""
}
}
}
}
stage('Functional Test AMI Build') {
steps {
dir('functional-test/packer') {
withAWS(role: 'PackerBuild', roleAccount: '123456789012', roleSessionName: 'Jenkins-Workflow-FunctionalTest-Packer') {
script {
sh """
# packer json script will require to copy contents from workspace, run the script to stash content
# packer json script will require to capture new AMI ID
# https://discuss.devopscube.com/t/how-to-get-the-ami-id-after-a-packer-build/36
# https://www.packer.io/docs/post-processors/manifest
packer validate FunctionalTestPacker.json
packer build -debug FunctionalTestPacker.json
# grab AMI ID and export as jenkins env variable
"""
}
}
}
}
}
stage('run groovy script to update AMI ID on EC2 plugin') {
steps {
dir(groovy job dir) {
script {
sh """
# run groovy job to update AMI on Jenkins EC2 plugin
# https://gist.github.com/vrivellino/97954495938e38421ba4504049fd44ea
"""
}
}
}
}
stage('Kickoff Functional Test Deploy') {
// pipeline checkbox parameter, when ticked it will automatically kick off the functional test pipeline
when {
expression {params.RUN_TESTS.toBoolean()}
}
steps {
script{
env.branch = params.BRANCH
sh """
echo "Branch is ${branch}"
"""
}
build job: 'workflow/CypressFunctionaTestDeployAndRun',
parameters: [
string(name: 'BRANCH', value: env.branch)
],
wait : false
}
}
}
post {
always {
cleanWs()
}
}
}
Create jenkins pipeline job 2:
This job will create the EC2 agents via the plugin from the customised AMI from pipeline job 1
This means your agents will have the same workspace ready to unstash - so you can execute a parallel run
Also you could move a lot of your user data script that is in the EC2 plugin as part of the customised AMI build, thus cut down the time for each EC2 agent to get ready to carry out execution
pipeline {
stages {
stage('E2E-PR-CYPRESS') {
when {
allOf {
expression {
return fileExists("cypress.json")
}
branch "PR-*"
}
}
}
parallel {
stage('Cypress Tests 1') {
agent { label 'aws_micro_slave_e2e' }
options { skipDefaultCheckout() }
steps {
runE2eTests()
}
}
stage('Cypress Tests 2') {
agent { label 'aws_micro_slave_e2e' }
options { skipDefaultCheckout() }
steps {
runE2eTests()
}
}
}
}
post {
always {
e2eAfterCypressRun(this, true)
}
}
}

Run parallel inside steps of a stage in declarative jenkins

So, I want to run my parallel stages inside a stage but I also want to write some shared code by each parallel stage which I have written in steps of parallel parent stage
The problem I faced is that that the parallel stages are not being run
stages {
stage('partent stage 1'){
something here
}
stage('parent stage 2') {
steps {
// common code for parallel stages
parallel {
stage ('1'){
// some shell command
}
stage('2') {
// some shell command
}
}
}
}
}
For executing shared code you can define variables and functions outside of the declarative pipeline:
def foo = true
def checkFoo {
return foo
}
pipeline {
stage('parallel stage') {
parallel {
stage('stage 1') {
steps {
script {
def baz = checkFoo()
}
sh “echo ${baz}”
}
}
stage('stage 2') {
steps {
script {
def baz = checkFoo()
}
sh “echo ${baz}”
}
}
}
}
}
You can also write a shared library, which you can use in all or certain jobs.
I’ve deleted my first answer, since it was pure BS.

Re-use agent in parallel stages of declarative pipeline

I'm using Declarative Pipelines 1.3.2 plugin and I want to use the same agent (as in only specifying the agent directive once) in multiple parallel stages:
stage('Parallel Deployment')
{
agent { dockerfile { label 'docker'; filename 'Dockerfile'; } }
parallel
{
stage('A') { steps { ... } }
stage('B') { steps { ... } }
}
}
However, Jenkins complains:
"agent" is not allowed in stage "Parallel Deployment" as it contains parallel stages
A solution is to duplicate the agent directive for each parallel stage, but this is tedious and leads to lot of duplicated code with many parallel stages:
stage('Parallel Deployment')
{
parallel
{
stage('A') {
agent { dockerfile { label 'docker'; filename 'Dockerfile'; } }
steps { ... }
}
stage('B') {
agent { dockerfile { label 'docker'; filename 'Dockerfile'; } }
steps { ... }
}
}
}
Is there a more idiomatic solution, or is duplicating agent directive necessary for each of the parallel stages?
Specifying the agent at pipeline level can be a solution, but has the potential downside that the agent is up & running for the whole duration of the build.
Also note that this means each stage (that doesn't define its own agent) is run on the same agent instance, not agent type. If the parallel processes are CPU / resource intensive, this might not be what you want.
Still, if you want to run parallel stages on one instance, and can't or want not to define the agent at pipeline level, here's a workaround for the declarative syntax:
stage('Parallel Deployment') {
agent { dockerfile { label 'docker'; filename 'Dockerfile'; } }
stages {
stage('A & B') {
parallel {
stage('A') { steps { ... } }
stage('B') { steps { ... } }
}
}
}
}
Or you go for a scripted pipeline, which doesn't have this limitation.
Declare the agent at Pipeline level so all stages run on the same agent.

Scripted jenkinsfile parallel stage

I am attempting to write a scripted Jenkinsfile using the groovy DSL which will have parallel steps within a set of stages.
Here is my jenkinsfile:
node {
stage('Build') {
sh 'echo "Build stage"'
}
stage('API Integration Tests') {
parallel Database1APIIntegrationTest: {
try {
sh 'echo "Build Database1APIIntegrationTest parallel stage"'
}
finally {
sh 'echo "Finished this stage"'
}
}, Database2APIIntegrationTest: {
try {
sh 'echo "Build Database2APIIntegrationTest parallel stage"'
}
finally {
sh 'echo "Finished this stage"'
}
}, Database3APIIntegrationTest: {
try {
sh 'echo "Build Database3APIIntegrationTest parallel stage"'
}
finally {
sh 'echo "Finished this stage"'
}
}
}
stage('System Tests') {
parallel Database1APIIntegrationTest: {
try {
sh 'echo "Build Database1APIIntegrationTest parallel stage"'
}
finally {
sh 'echo "Finished this stage"'
}
}, Database2APIIntegrationTest: {
try {
sh 'echo "Build Database2APIIntegrationTest parallel stage"'
}
finally {
sh 'echo "Finished this stage"'
}
}, Database3APIIntegrationTest: {
try {
sh 'echo "Build Database3APIIntegrationTest parallel stage"'
}
finally {
sh 'echo "Finished this stage"'
}
}
}
}
I want to have 3 stages: Build; Integration Tests and System Tests.
Within the two test stages, I want to have 3 sets of the tests executed in parallel, each one against a different database.
I have 3 available executors. One on the master, and 2 agents and I want each parallel step to run on any available executor.
What I've noticed is that after running my pipeline, I only see the 3 stages, each marked out as green. I don't want to have to view the logs for that stage to determine whether any of the parallel steps within that stage were successful/unstable/failed.
I want to be seeing the 3 steps within my test stages - marked as either green, yellow or red (Success, unstable or failed).
I've considered expanding the tests out into their own stages, but have realised that parallel stages are not supported (Does anyone know whether this will ever be supported?), so I cannot do this as the pipeline would take far too long to complete.
Any insight would be much appreciated, thanks
In Jenkins scripted pipeline, parallel(...) takes a Map describing each stage to be built. Therefore you can programatically construct your build stages up-front, a pattern which allows flexible serial/parallel switching.
I've used code similar to this where the prepareBuildStages returns a List of Maps, each List element is executed in sequence whilst the Map describes the parallel stages at that point.
// main script block
// could use eg. params.parallel build parameter to choose parallel/serial
def runParallel = true
def buildStages
node('master') {
stage('Initialise') {
// Set up List<Map<String,Closure>> describing the builds
buildStages = prepareBuildStages()
println("Initialised pipeline.")
}
for (builds in buildStages) {
if (runParallel) {
parallel(builds)
} else {
// run serially (nb. Map is unordered! )
for (build in builds.values()) {
build.call()
}
}
}
stage('Finish') {
println('Build complete.')
}
}
// Create List of build stages to suit
def prepareBuildStages() {
def buildStagesList = []
for (i=1; i<5; i++) {
def buildParallelMap = [:]
for (name in [ 'one', 'two', 'three' ] ) {
def n = "${name} ${i}"
buildParallelMap.put(n, prepareOneBuildStage(n))
}
buildStagesList.add(buildParallelMap)
}
return buildStagesList
}
def prepareOneBuildStage(String name) {
return {
stage("Build stage:${name}") {
println("Building ${name}")
sh(script:'sleep 5', returnStatus:true)
}
}
}
The resulting pipeline appears as:
There are certain restrictions on what can be nested within a parallel block, refer to the pipeline documentation for exact details. Unfortunately much of the reference seems biased towards declarative pipeline, despite it being rather less flexible than scripted (IMHO).
The pipeline examples page was the most helpful.
Here's a simple example without loops or functions based on #Ed Randall's post:
node('docker') {
stage('unit test') {
parallel([
hello: {
echo "hello"
},
world: {
echo "world"
}
])
}
stage('build') {
def stages = [:]
stages["mac"] = {
echo "build for mac"
}
stages["linux"] = {
echo "build for linux"
}
parallel(stages)
}
}
...which yields this:
Note that the values of the Map don't need to be stages. You can give the steps directly.
Here is an example from their docs:
Parallel execution
The example in the section above runs tests across two different platforms in a linear series. In practice, if the make check execution takes 30 minutes to complete, the "Test" stage would now take 60 minutes to complete!
Fortunately, Pipeline has built-in functionality for executing portions of Scripted Pipeline in parallel, implemented in the aptly named parallel step.
Refactoring the example above to use the parallel step:
// Jenkinsfile (Scripted Pipeline)
stage('Build') {
/* .. snip .. */
}
stage('Test') {
parallel linux: {
node('linux') {
checkout scm
try {
unstash 'app'
sh 'make check'
}
finally {
junit '**/target/*.xml'
}
}
},
windows: {
node('windows') {
/* .. snip .. */
}
}
}
To simplify the answer of #Ed Randall here.
Remember this is Jenkinsfile scripted (not declarative)
stage("Some Stage") {
// Stuff ...
}
stage("Parallel Work Stage") {
// Prealocate dict/map of branchstages
def branchedStages = [:]
// Loop through all parallel branched stage names
for (STAGE_NAME in ["Branch_1", "Branch_2", "Branch_3"]) {
// Define and add to stages dict/map of parallel branch stages
branchedStages["${STAGE_NAME}"] = {
stage("Parallel Branch Stage: ${STAGE_NAME}") {
// Parallel stage work here
sh "sleep 10"
}
}
}
// Execute the stages in parallel
parallel branchedStages
}
stage("Some Other Stage") {
// Other stuff ...
}
Please pay attention to the curly braces.
This will result in the following result (with the BlueOcean Jenkins Plugin):
I was also trying similar sort of steps to execute parallel stages and display all of them in a stage view. You should write a stage inside a parallel step as shown in the following code block.
// Jenkinsfile (Scripted Pipeline)
stage('Build') {
/* .. Your code/scripts .. */
}
stage('Test') {
parallel 'linux': {
stage('Linux') {
/* .. Your code/scripts .. */
}
}, 'windows': {
stage('Windows') {
/* .. Your code/scripts .. */
}
}
}
The above example with a FOR is wrong, as varible STAGE_NAME will be overwritten everytime, I had the same problem as Wei Huang.
Found the solution here:
https://www.convalesco.org/notes/2020/05/26/parallel-stages-in-jenkins-scripted-pipelines.html
def branchedStages = [:]
def STAGE_NAMES = ["Branch_1", "Branch_2", "Branch_3"]
STAGE_NAMES.each { STAGE_NAME ->
// Define and add to stages dict/map of parallel branch stages
branchedStages["${STAGE_NAME}"] = {
stage("Parallel Branch Stage: ${STAGE_NAME}") {
// Parallel stage work here
sh "sleep 10"
}
}
}
parallel branchedStages
I have used as below where the three stages are parallel.
def testCases() {
stage('Test Cases') {
def stages = [:] // declaring empty list
stages['Unit Testing'] = {
sh "echo Unit Testing completed"
}
stages['Integration Testing'] = {
sh "echo Integration Testing completed"
}
stages['Function Testing'] = {
sh "echo Function Testing completed"
}
parallel(stages) // declaring parallel stages
}
}
I have used stage{} in parallel blocks several times. Then each stage shows up in the Stage view. The parent stage that contains parallel doesn't include the timing for all the parallel stages, but each parallel stage shows up in stage view.
In blue ocean, the parallel stages appear separately instead of the stages showing. If there is a parent stage, it shows as the parent of the parallel stages.
If you don't have the same experience, maybe a plugin upgrade is due.

How do I assure that a Jenkins pipeline stage is always executed, even if a previous one failed?

I am looking for a Jenkinsfile example of having a step that is always executed, even if a previous step failed.
I want to assure that I archive some builds results in case of failure and I need to be able to have an always-running step at the end.
How can I achieve this?
We switched to using Jenkinsfile Declarative Pipelines, which lets us do things like this:
pipeline {
agent any
stages {
stage('Test') {
steps {
sh './gradlew check'
}
}
}
post {
always {
junit 'build/reports/**/*.xml'
}
}
}
References:
Tests and Artifacts
Jenkins Pipeline Syntax
try {
sh "false"
} finally {
stage 'finalize'
echo "I will always run!"
}
Another possibility is to use a parallel section in combination with a lock. For example:
pipeline {
stages {
parallel {
stage('Stage 1') {
steps {
lock('MY_LOCK') {
echo 'do stuff 1'
}
}
}
stage('Stage 2') {
steps {
lock('MY_LOCK') {
echo 'do stuff 2'
}
}
}
}
}
}
Parallel stages in a parallel section only abort other stages in the same parallel section if the fail fast option for the parallel section is set. See the docs.

Resources