How to pass variables from a build to another in Jenkins? - jenkins

Due to infrastructure constraints, in my Jenkinsfile, I would like to store some variables from build #1 and be able to access them from build #2 and next ones.
I tried to set some env variables, but it seems they are not saved from a build to another.
Is there to acheive that from Jenkinsfile? Or maybe to write them to a text file?
Jenkins version: 2.111

Yes, write them to a text file, and store that as a build artifact in build#1.
Later builds can access the text file as build#1's build artifact (via Web interface, or on disk if running on master).

I finally use this mecanism which fits my requirements and works like a charm, so far:
if (currentBuild.previousBuild != null) {
env.MY_VAR = currentBuild.previousBuild.getBuildVariables().get('MY_VAR ')
echo "Old branch context restored"
} else {
env.MY_VAR = createSomethingAtFirstBuild()
echo "New branch context created"
}

Related

PullRequest Build Validation with Jenkins and OnPrem Az-Devops

First off the setup in question:
A Jenkins Instance with several build nodes and on prem Azure-Devops server containing the Git Repositories.
The Repo in question is too large to always build on push for all branches and all devs, so a small workaround was done:
The production branches have a polling enabled twice a day (because of testing duration which is handled downstream more builds would not help with quality)
All other branches have their automated building suppressed. They still can start it manually for Builds/Deployments/Unittests if they so choose.
The jenkinsfile has parameterization for which platforms to build, on prod* all the platforms are true, on all other branches false.
This helps because else the initial build of a feature branch would always build/deploy locally all platforms which would take too much of a load on the server infrastructure.
I added a service endpoint for Jenkins in the Azure Devops, added a Buildvalidation .yml - this basically works because when I call the sourcebranch of the pull request with the merge commitID i added a parameter
isPullRequestBuild which contains the ID of the PR.
snippet of the yml:
- task: JenkinsQueueJob#2
inputs:
serverEndpoint: 'MyServerEndpoint'
jobName: 'MyJob'
isMultibranchJob: true
captureConsole: true
capturePipeline: true
isParameterizedJob: true
multibranchPipelineBranch: $(System.PullRequest.SourceBranch)
jobParameters: |
stepsToPerform=Build
runUnittest=true
pullRequestID=$(System.PullRequest.PullRequestId)
Snippet of the Jenkinsfile:
def isPullRequest = false
if ( params.pullRequestID?.trim() )
{
isPullRequest = true
//do stuff to change how the pipeline should react.
}
In the jenkinsfile I look whether the parameter is not empty and reset the platforms to build to basically all and to run the unittests.
The problem is: if the branch has never run, Jenkins does not already know the parameter in the first run, so it is ignored, building nothing, and returning with 0 because "nothing had to be done".
Is there any way to only run the jenkins build if it hasnt run already?
Or is it possible to get information from the remote call if this was the build with ID 1?
The only other thing would be to Call the Jenkins via web api and check for the last successful build, but in that case I would have have the token somewhere stored in source control.
Am I missing something obvious here? I dont want to trigger the feature branch builds to do nothing more than once, because Devs could lose useful information about their started builds/deployments.
Any ideas appreciated
To whom it may concern with similar problems:
In the end I used the following workaround:
The Jenkins Endpoint is called via a user that only is used for automated builds. So, in case that this user triggered the build, I set everything to run a Pull Request Validation, even if it is the first build. Along the lines of
def causes = currentBuild.getBuildCauses('hudson.model.Cause$UserIdCause')
if (causes != null)
{
def buildCauses= readJSON text: currentBuild.getBuildCauses('hudson.model.Cause$UserIdCause').toString()
buildCauses.each
{
buildCause ->
if (buildCause['userId'] == "theNameOfMyBuildUser")
{
triggeredByAzureDevops = true
}
}
}
getBuildcauses must be allowed to run by a Jenkins Admin for that to work.

jenkins declarative pipeline ignoring changelog of jenkinsfiles

I have apps and their codes on git repositories. Also jenkinsfiles for building apps and these files on another repository. The problem is jenkins builds changelog. Jenkins add jenkinsfiles changelog to build changesets and I don't want to that. Because these changes are according to infrastructure not relevant with apps. How to prevent this? I didn't find any workaround or solution.
If I got well your question... I don't think you can remove Jenkinsfile changes from the change set that Jenkins reads from git, but instead, you can skip your pipeline to build if there are only changes on Jenkinsfile.
If it helps...
First place, you need to read the change set:
def changedFiles = []
for (changeLogSet in currentBuild.changeSets) {
for (entry in changeLogSet.getItems()) {
for (file in entry.getAffectedFiles()) {
changedFiles.add(file.getPath())
}
}
}
Then, you can check if it is only Jenkinsfile:
if (changedFiles.size() == 1 && changedFiles[0] == "Jenkinsfile"){
println "Only Jenkinsfile has changed... Skipping build..."
currentBuild.getRawBuild().getExecutor().interrupt(Result.SUCCESS) // this skips your build prematurely and makes the rest of the stages green
sleep(1) // you just need this
}else{
println "There are other changes rather than only Jenkinsfile, build will proceed."
}
P.S. You have several ways to terminate the jobs earlier without failing the build, but this one is the cleanest in my experience, even though you need to allow some Admin Signatures Permission on Jenkins (I've seen it in another thread here some time ago, can't find it now though)

Jenkins is re-using a pipeline workspace and I wish for each build to have a unique workspace

So, most of the questions and answers I've found on this subject is for people who want to use the SAME workspace for different runs. (Which baffles me, but then I require a clean slate each time I start a job. Leftover stuff will only break things)
My issue is the EXACT opposite - I MUST have a separate workspace for each run (or I need to know how to create files with the same name in different runs that stay with that run only, and which are easily reachable from bash scripts started by the pipeline!)
So, my question is - how do I either force Jenkins to NOT use the same workspace for two concurrently-running jobs on different hosts, OR what variable can I use in the 'custom workspace' field to accomplish this?
After I responded to the question by #Joerg S I realized that I'm saying the thing that Joerg S says CAN'T happen is EXACTLY what I'm observing! Jenkins is using the SAME workspace for 2 different, concurrent, jobs on 2 different hosts. Is this a Jenkins pipeline bug?
See below for a bewildering amount of information.
Given the way I have to go onto and off of nodes during the run, I've found that I can start 2 different builds on different hosts of the same job, and they SHARE the workspace dir! Since each job has shell scripts which are busy writing files into that directory, this is extremely bad.
In Custom workspace in jenkins we are told to use custom workspace, and I'm set up just like that
In Jenkins: how to run builds in unique directories we are told to use ${BUILD_NUMBER} in the above custom workspace field, so what I tried was:
${JENKINS_HOME}/workspace/${ITEM_FULLNAME}/${BUILD_NUMBER}
All that happens to me when I use that is that the workspace name is, you guessed it, "${BUILD_NUMBER}" (and I even got a "${BUILD_NUMBER}#2" just for good measure!)
I tried {$BUILD_ID}, same thing (uses that literally, does not substitute the number).
I have the 'allow concurrent builds' turned on.
I'm using pipelines exclusively.
All jobs here, as part of normal execution, cause the slave, non-master host to reboot into an OS that does not have the capability to run slave.jar (indeed, it has no network access at all), so I cannot run the entire pipeline on that host.
All jobs use the following construct somewhere inside them:
tests=Arrays.asList(tests.split("\\r?\n"))
shellerror=231
for( line in tests){
So let's call an example job 'foo' that loops through a list, as above, that I want to run on 2 different hosts. The pipeline for that job starts running on master (since the above for (line in tests) is REQUIRED to run on a node!)). Then goes back and forth between master and slave, often multiple times.
If I start this job on host A and host B at about the same time, they will BOTH use the workspace ${JENKINS_HOME}/workspace/${JOB_NAME}, or in my case /var/lib/jenkins/jenkins/workspace/job
Since they write different data to files with the same name in that directory, I'm clearly totally broken immediately.
So, how do I force Jenkins to use a unique workspace EVERY SINGLE JOB?
Or, what???
Other things: pipeline build step version 2.5.1, Jenkins 2.46.2
I've been trying to get the workspace statement ('ws') to work, but that doesn't quite work as I expected either - some files are in the workspace I explicitly name, and some are still in the 'built-in' workspace (workspace/).
I was asked to provide code. The 'standard' pipeline I use is about 26K bytes, composing about 590 lines. So, I'm going to GREATLY reduce. That being said:
node("master") { // 1
..... lots of stuff....
} // this matches the "node('master')" above
node(HOST) {
echo "on $HOST, check what os"
if (isUnix())
...some more stuff...
} // end of 'node(HOST)' above
if (isok == 0 ) {
node("master") {
echo "----------------- Running on MASTER 19 $shellerror waiting on boot out of windows ------------"
sleep 120
echo "----------------- Leaving MASTER ------------"
}
}
... lots 'o code ...
node(HOST) {
... etc
} // matches the latest 'node HOST' above
node("master") { // 120
.... code ...
for( line in tests) {
...code...
}
}
... and on and on and on, switching back and forth from one to the other
FWIW, when I tried to make the above use 'ws' so that I could make certain the ws name was unique, I simply added a 'ws wsname' block directly under (almost) every 'node' opening so it was
node(name) { ws (wsname) { ..stuff that was in node block before... } }
But then I've got two directories to worry about checking - both the 'default' workspace/jobname dir AND the new wsname one.
Try using customWorkspace node common option:
pipeline {
agent {
node {
label 'node(s)-defined-label'
customWorkspace "${JENKINS_HOME}/workspace/${JOB_NAME}/${BUILD_NUMBER}"
}
}
stages {
// Your pipeline logic here
}
}
customWorkspace
A string. Run the Pipeline or individual stage this
agent is applied to within this custom workspace, rather than the
default. It can be either a relative path, in which case the custom
workspace will be under the workspace root on the node, or an absolute
path.
Edit
Since this doesn't work for your complex pipeline. Maybe try this silly solution:
def WORKSPACE = "${JENKINS_HOME}/workspace/${JOB_NAME}/${BUILD_NUMBER}"
node(HOST) {
sh(script: "mkdir -p ${WORKSPACE}")
sh(script: "cd ${WORKSPACE}")
//Do stuff here
}
or if dir() is accessible:
def WORKSPACE = "${JENKINS_HOME}/workspace/${JOB_NAME}/${BUILD_NUMBER}"
node(HOST) {
sh(script: "mkdir -p ${WORKSPACE}")
dir(WORKSPACE) {
//Do stuff here
}
}
customWorkspace didn't work for me.
What worked:
stages {
stage("SCM (For commit trigger)"){
steps {
ws('custom-workspace') { // Because we don't want to switch from the pipeline checkout
// Generated from http://lstool01:8080/job/Permanent%20Build/pipeline-syntax/
checkout(xxx)
}
}
}
'${SOMEVAR}'
will not get substituted
"${SOMEVAR}"
will - this is how groovy strings are being handled
see groovy string handling
so if you have a
ws("/some/path/somewhere/${BUILD_ID}")
{
//something
}
on your node in your pipeline Jenkinsfile it should do the trick in this regard
the problem with #2 workspaces can occur when you allow concurrent builds of the project - I had the exact same problem with a custom ws() with #2 - simply disallow concurrent builds or work around that.

Jenkins, how to check regressions against another job

When you set up a Jenkins job various test result plugins will show regressions if the latest build is worse than the previous one.
We have many jobs for many projects on our Jenkins and we wanted to avoid having a 'job per branch' set up. So currently we are using a parameterized build to build eg different development branches using a single job.
But that means when I build a new branch any regressions are measured against the previous build, which may be for a different branch. What I really want is to measure regressions in a feature branch against the latest build of the master branch.
I thought we should probably set up a separate 'master' build alongside the parameterized 'branches' build. But I still can't see how I would compare results between jobs. Is there any plugin that can help?
UPDATE
I have started experimenting in the Script Console to see if I could write a post-build script... I have managed to get the latest build of master branch in my parameterized job... I can't work out how to get to the test results from the build object though.
The data I need is available in JSON at
http://<jenkins server>/job/<job name>/<build number>/testReport/api/json?pretty=true
...if I could just get at this data structure it would be great!
I tried using JsonSlurper to load the json via HTTP but I get 403, I guess because my script has no auth session.
I guess I could load the xml test results from disk and parse them in my script, it just seems a bit stupid when Jenkins has already done this.
I eventually managed to achieve everything I wanted, using a Groovy script in the Groovy Postbuild Plugin
I did a lot of exploring using the script console http://<jenkins>/script and also the Jenkins API class docs are handy.
Everyone's use is going to be a bit different as you have to dig down into the build plugins to get the info you need, but here's some bits of my code which may help.
First get the build you want:
def getProject(projectName) {
// in a postbuild action use `manager.hudson`
// in the script web console use `Jenkins.instance`
def project = manager.hudson.getItemByFullName(projectName)
if (!project) {
throw new RuntimeException("Project not found: $projectName")
}
project
}
// CloudBees folder plugin is supported, you can use natural paths:
project = getProject('MyFolder/TestJob')
build = project.getLastCompletedBuild()
The main test results (jUnit etc) seem to be available directly on the build as:
result = build.getTestResultAction()
// eg
failedTestNames = result.getFailedTests().collect{ test ->
test.getFullName()
}
To get the more specialised results from eg Violations plugin or Cobertura code coverage you have to look for a specific build action.
// have a look what's available:
build.getActions()
You'll see a list of stuff like:
[hudson.plugins.git.GitTagAction#2b4b8a1c,
hudson.scm.SCMRevisionState$None#40d6dce2,
hudson.tasks.junit.TestResultAction#39c99826,
jenkins.plugins.show_build_parameters.ShowParametersBuildAction#4291d1a5]
These are instances, the part in front of the # sign is the class name so I used that to make this method for getting a specific action:
def final VIOLATIONS_ACTION = hudson.plugins.violations.ViolationsBuildAction
def final COVERAGE_ACTION = hudson.plugins.cobertura.CoberturaBuildAction
def getAction(build, actionCls) {
def action = build.getActions().findResult { act ->
actionCls.isInstance(act) ? act : null
}
if (!action) {
throw new RuntimeException("Action not found in ${build.getFullDisplayName()}: ${actionCls.getSimpleName()}")
}
action
}
violations = getAction(build, VIOLATIONS_ACTION)
// you have to explore a bit more to find what you're interested in:
pylint_count = violations?.getReport()?.getViolations()?."pylint"
coverage = getAction(build, COVERAGE_ACTION)?.getResults()
// if you println it looks like a map but it's really an Enum of Ratio objects
// convert to something nicer to work with:
coverage_map = coverage.collectEntries { key, val -> [key.name(), val.getPercentageFloat()] }
With these building blocks I was able to put together a post-build script which compared the results for two 'unrelated' build jobs, then using the Groovy Postbuild plugin's helper methods to set the build status.
Hope this helps someone else.

How to get build time stamp from Jenkins build variables?

How can I get build time stamp of the latest build from Jenkins?
I want to insert this value in the Email subject in post build actions.
Build Timestamp Plugin will be the Best Answer to get the TIMESTAMPS in the Build process.
Follow the below Simple steps to get the "BUILD_TIMESTAMP" variable enabled.
STEP 1:
Manage Jenkins -> Plugin Manager -> Installed...
Search for "Build Timestamp Plugin".
Install with or without Restart.
STEP 2:
Manage Jenkins -> Configure System.
Search for 'Build Timestamp' section, then Enable the CHECKBOX.
Select the TIMEZONE, TIME format you want to setup with..Save the Page.
USAGE:
When Configuring the Build with ANT or MAVEN,
Please declare a Global variable as,
E.G. btime=${BUILD_TIMESTAMP}
(use this in your Properties box in ANT or MAVEN Build Section)
use 'btime' in your Code to any String Variables etc..
NOTE: This changed in Jenkins 1.597, Please see here for more info regarding the migration
You should be able to view all the global environment variables that are available during the build by navigating to https://<your-jenkins>/env-vars.html.
Replace https://<your-jenkins>/ with the URL you use to get to Jenkins webpage (for example, it could be http://localhost:8080/env-vars.html).
One of the environment variables is :
BUILD_ID
The current build id, such as "2005-08-22_23-59-59" (YYYY-MM-DD_hh-mm-ss)
If you use jenkins editable email notification, you should be able to use ${ENV, var="BUILD_ID"} in the subject line of your email.
One way this can be done is using shell script in global environment section, here, I am using UNIX timestamp but you can use any shell script syntax compatible time format:
pipeline {
agent any
environment {
def BUILDVERSION = sh(script: "echo `date +%s`", returnStdout: true).trim()
}
stages {
stage("Awesome Stage") {
steps {
echo "Current build version :: $BUILDVERSION"
}
}
}
}
Try use Build Timestamp Plugin and use BUILD_TIMESTAMP variable.
Generate environment variables from script (Unix script) :
echo "BUILD_DATE=$(date +%F-%T)"
I know its late replying to this question, but I have recently found a better solution to this problem without installing any plugin. We can create a formatted version number and can then use the variable created to display the build date/time.
Steps to create: Build Environment --> Create a formatted version number:
Environment Variable Name: BUILD_DATE
Version Number Format String: ${BUILD_DATE_FORMATTED}
thats it. Just use the variable created above in the email subject line as ${ENV, var="BUILD_DATE"} and you will get the date/time of the current build.
You can use the Jenkins object to fetch the start time directly
Jenkins.getInstance().getItemByFullName(<your_job_name>).getBuildByNumber(<your_build_number>).getTime()
also answered it here:
https://stackoverflow.com/a/63074829/1968948
BUILD_ID used to provide this information but they changed it to provide the Build Number since Jenkins 1.597. Refer this for more information.
You can achieve this using the Build Time Stamp plugin as pointed out in the other answers.
However, if you are not allowed or not willing to use a plugin, follow the below method:
def BUILD_TIMESTAMP = null
withCredentials([usernamePassword(credentialsId: 'JenkinsCredentials', passwordVariable: 'JENKINS_PASSWORD', usernameVariable: 'JENKINS_USERNAME')]) {
sh(script: "curl https://${JENKINS_USERNAME}:${JENKINS_PASSWORD}#<JENKINS_URL>/job/<JOB_NAME>/lastBuild/buildTimestamp", returnStdout: true).trim();
}
println BUILD_TIMESTAMP
This might seem a bit of overkill but manages to get the job done.
The credentials for accessing your Jenkins should be added and the id needs to be passed in the withCredentials statement, in place of 'JenkinsCredentials'. Feel free to omit that step if your Jenkins doesn't use authentication.
This answer below shows another method using "regexp feature of the Description Setter Plugin" which solved my problem as I could not install new plugins on Jenkins due to permission issues:
Use build timestamp in setting build description Jenkins
If you want add a timestamp to every request from browser to jenkins server.
You can refer to the jenkins crumb issuer mechanism, and you can hack the /scripts/hudson-behavior.js add modify here. so it will transform a timestamp to server.
/**
* Puts a hidden input field to the form so that the form submission will have the crumb value
*/
appendToForm : function(form) {
// add here. ..... you code
if(this.fieldName==null) return; // noop
var div = document.createElement("div");
div.innerHTML = "<input type=hidden name='"+this.fieldName+"' value='"+this.value+"'>";
form.appendChild(div);
}

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