Jenkins Pipeline as Code with Docker Error - docker

For one of my projects that I have on GitHub, I wanted to build it as a docker image and push it to my docker hub. The project is a sbt one with a Scala codebase.
Here is how my JenkinsFile is defined:
#!groovy
node {
// set this in Jenkins server under Manage Jenkins > Credentials > System > Global Credentials
docker.withRegistry('https://hub.docker.com/', 'joesan-docker-hub-credentials') {
git credentialsId: '630bd271-01e7-48c3-bc5f-5df059c1abb8', url: 'https://github.com/joesan/monix-samples.git'
sh "git rev-parse HEAD > .git/commit-id"
def commit_id = readFile('.git/commit-id').trim()
println comit_id
stage "build" {
def app = docker.build "Monix-Sample"
}
stage "publish" {
app.push 'master'
app.push "${commit_id}"
}
}
}
When I tried to run this from my Jenkins server, I get the following error:
java.io.FileNotFoundException
at jenkins.plugins.git.GitSCMFile$3.invoke(GitSCMFile.java:167)
at jenkins.plugins.git.GitSCMFile$3.invoke(GitSCMFile.java:159)
at jenkins.plugins.git.GitSCMFileSystem$3.invoke(GitSCMFileSystem.java:161)
at org.jenkinsci.plugins.gitclient.AbstractGitAPIImpl.withRepository(AbstractGitAPIImpl.java:29)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.withRepository(CliGitAPIImpl.java:65)
at jenkins.plugins.git.GitSCMFileSystem.invoke(GitSCMFileSystem.java:157)
at jenkins.plugins.git.GitSCMFile.content(GitSCMFile.java:159)
at jenkins.scm.api.SCMFile.contentAsString(SCMFile.java:338)
at org.jenkinsci.plugins.workflow.cps.CpsScmFlowDefinition.create(CpsScmFlowDefinition.java:101)
at org.jenkinsci.plugins.workflow.cps.CpsScmFlowDefinition.create(CpsScmFlowDefinition.java:59)
at org.jenkinsci.plugins.workflow.job.WorkflowRun.run(WorkflowRun.java:232)
at hudson.model.ResourceController.execute(ResourceController.java:98)
at hudson.model.Executor.run(Executor.java:404)
Finished: FAILURE
Since this is running inside a VM on Azure, I thought the VM was not able to reach outside, but that seems not to be the case as I was able to ssh into the VM and git pull from the Git repo. So what is the problem here? How could I make this work?

for me unchecking "lightweight checkout" fixed the issue

I experienced the exact same error. My setting:
Pipeline build inside a dockerized Jenkins (version 2.32.3)
In the configuration of the job, I specified a check out into a subdirectory: Open the configuration, e.g. https://myJenkins/job/my-job/configure. At the bottom, see section Pipeline -> Additional Behaviours -> Check out into a sub-directory with Local subdirectory for repo set to, e.g., my-sub-dir.
Expectation: Upon check out, the Jenkinsfile ends up in my-sub-dir/Jenkinsfile.
Via the option Script path, you configure the location of the Jenkinsfile so that Jenkins can start the build. I put my-sub-dir/Jenkinsfile as value.
I then received the exception you pasted in your question. I fixed it by setting Script Path to Jenkinsfile. If you don't specify a sub-directory for check out, then still try double checking values for Script Path.
Note: I have another Jenkins instance at work. There I have to specify Script Path including the custom check out sub-directory (as mentioned in Expectation above).

GO TO Job-->Config-->Pipline and uncheck checkbox lightweight checkout"
lightweight checkout : selected, try to obtain the Pipeline script contents >directly from
the SCM without performing a full checkout. The advantage of this mode
is its efficiency; however, you will not get any changelogs or polling
based on the SCM. (If you use checkout scm during the build, this will
populate the changelog and initialize polling.) Also build parameters
will not be substituted into SCM configuration in this mode. Only
selected SCM plugins support this mode.

Related

Notifications on jenkins job failures - with pipeline from scm

We have several jenkins pipeline jobs setup as "pipeline from scm" that checkout a jenkins file from github and runs it. There is sufficient try/catch based error handling inside the jenkinsfile to trap error conditions and notify the right channels.This blog post goes into a quite a bit of depth about how to achieve this.
However, if there is issue fetching the jenkinsfile in the first place, the job fails silently. How does one generate notifications from general job launch failures before the pipeline is even started?
Jenkins SCM pipeline doesn't have any execution provision similar to catch/finally that will be called if Jenkinsfile load is failed, And I don't think there will be any in future.
However there is this global-post-script which runs groovy script after every build of every job on Jenkins. You have to place that script in $JENKINS_HOME/global-post-script/ directory.
Using this you can send notifications or email to admins based on project that failed and/or reason/exceptions of failure.
Sample code that you can put in script
if ("$BUILD_RESULT" != 'SUCCESS') {
def job = hudson.model.Hudson.instance.getItem("$JOB_NAME")
def build = job.getBuild("$BUILD_NUMBER")
def exceptionsToHandle = ["java.io.FileNotFoundException","hudson.plugins.git.GitException"]
def foundExection = build
.getLog()
.split('\n')
.toList()
.stream()
.filter{ line ->
!line.trim().isEmpty() && !exceptionsToHandle.stream().filter{ex -> line.contains(ex)}.collect().isEmpty()
}
.collect()
.size() > 0;
println "do something with '$foundExection'"
}
You can validate your Jenkinsfile before pushing it to repository.
Command-line Pipeline Linter
There are some IDE Integrations as well
Apparently this is an open issue with Jenkins: https://issues.jenkins.io/browse/JENKINS-57946
I have decided not to use Yogesh answer mentioned earlier. For me it is simpler to just copy the content of the Jenkinsfile directly into the Jenkins project instead of pointing Jenkins to the GIT location of the Jenkinsfile. However, in addition I keep the Jenkinsfile in GIT. But make sure to keep the GIT and the Jenkins version identical.

Jenkins pipeline run gradle tasks within sshagent

I'm creating a jenkins pipeline which utilizes a build.gradle script to build the project.
One of the first things gradle does is check out some git repos, I need to run this with ssh, so I thought I could wrap the code in sshagent like this:
sshagent(['c6f7cd1b-9bb3-4b33-9db0-cbd1f62cd0ba']){
sh 'git clone git#Repo.git'
}
the Id is mapped to a global jenkins credential with the private key in it, I also use it in another pipeline to tag a repo and push it to master, using the same credentialId.
However I get following output when trying to run the pipeline:
FATAL: [ssh-agent] Could not find specified credentials
I have no idea why I get this, when I'm using a copy paste from the other pipeline.
Anyone who can point me towards the right direction?
Thx

Jenkins Shared Libraries context

I have a pipeline job which loads Jenkinsfile from git repository. My Jenkinsfile looks like this:
#!groovy
#Library('global-utils-lib') _
node("mvn") {
stage('build') {
checkout scm
}
stage('merge-request'){
mergeRequest()
}
}
global-utils-lib is shared library loaded in Global Pipeline Libraries from another git repo with following structure
vars/mergeRequest.groovy
mergeRequest.groovy:
def call() {
sh "ip addr"
def workspacePath = env.WORKSPACE
new File(workspacePath + "/file.txt").text
}
Job is run against docker container (docker plugin).
When I run this job then docker container is provisioned correctly and scm is downloaded but I get FileNotFoundException.
It looks like code from shared library is executed against jenkins master not slave:
presented IP comes from master
file is loaded correctly when I pass correct path to the scm on master
How can I run library code against slave? What I am missing?
It's generally not a good idea to try and do things like new File() instead of using existing Pipeline steps.
Your Pipeline script is interpreted and executed by the Jenkins master so, as you're seeing, the attempt to use the File API doesn't work as you might expect.
Sticking to Pipeline steps helps ensure that your pipeline is durable (i.e. survives restarts), is pausable, and doesn't block the execution thread, preventing parallel steps from working, for example.
In this case, the existing readFile step can be used.
I don't know how well the Docker Plugin interacts with Pipeline (though I imagine it should be transparent), and without knowing which agents have the "mvn" label, or whether you can reproduce this outside of a shared library, it's unclear why your sh step would appear to be running on the master.
The Docker Pipeline Plugin is explicitly designed for Pipeline, so it might give better results.

How can I test a change made to Jenkinsfile locally?

When writing jenkins pipelines it seems to be very inconvenient to commit each new change in order to see if it works.
Is there a way to execute these locally without committing the code?
You cannot execute a Pipeline script locally, since its whole purpose is to script Jenkins. (Which is one reason why it is best to keep your Jenkinsfile short and limited to code which actually deals with Jenkins features; your actual build logic should be handled with external processes or build tools which you invoke via a one-line sh or bat step.)
If you want to test a change to Jenkinsfile live but without committing it, use the Replay feature added in 1.14.
JENKINS-33925 tracks the feature request for an automated test framework.
I have a solution that works well for me. It consists of a local jenkins running in docker and a git web hook to trigger the pipeline in the local jenkins on every commit. You no longer need to push to your github or bitbucket repository to test the pipeline.
This has only been tested in a linux environment.
It is fairly simple to make this work although this instruction is a tad long. Most steps are there.
This is what you need
Docker installed and working. This is not part of this instruction.
A Jenkins running in docker locally. Explained how below.
The proper rights (ssh access key) for your local Jenkins docker user to pull from your local git repo. Explained how below.
A Jenkins pipeline project that pulls from your local git repository. Explained below.
A git user in your local Jenkins with minimal rights. Explained below.
A git project with a post-commit web hook that triggers the pipeline project. Explained below.
This is how you do it
Jenkins Docker
Create a file called Dockerfile in place of your choosing. I'm placing it in /opt/docker/jenkins/Dockerfile fill it with this:
FROM jenkins/jenkins:lts
USER root
RUN apt-get -y update && apt-get -y upgrade
# Your needed installations goes here
USER jenkins
Build the local_jenkins image
This you will need to do only once or after you have added something to the Dockerfile.
$ docker build -t local_jenkins /opt/docker/jenkins/
Start and restart local_jenkins
From time to time you want to start and restart jenkins easily. E.g. after a reboot of your machine. For this I made an alias that I put in .bash_aliases in my home folder.
$ echo "alias localjenkinsrestart='docker stop jenkins;docker rm jenkins;docker run --name jenkins -i -d -p 8787:8080 -p 50000:50000 -v /opt/docker/jenkins/jenkins_home:/var/jenkins_home:rw local_jenkins'" >> ~/.bash_aliases
$ source .bash_aliases # To make it work
Make sure the /opt/docker/jenkins/jenkins_home folder exists and that you have user read and write rights to it.
To start or restart your jenkins just type:
$ localjenkinsrestart
Everything you do in your local jenkins will be stored in the folder /opt/docker/jenkins/jenkins_home and preserved between restarts.
Create a ssh access key in your docker jenkins
This is a very important part for this to work. First we start the docker container and create a bash shell to it:
$ localjenkinsrestart
$ docker exec -it jenkins /bin/bash
You have now entered into the docker container, this you can see by something like jenkins#e7b23bad10aa:/$ in your terminal. The hash after the # will for sure differ.
Create the key
jenkins#e7b23bad10aa:/$ ssh-keygen
Press enter on all questions until you get the prompt back
Copy the key to your computer. From within the docker container your computer is 172.17.0.1 should you wonder.
jenkins#e7b23bad10aa:/$ ssh-copy-id user#172.17.0.1
user = your username and 172.17.0.1 is the ip address to your computer from within the docker container.
You will have to type your password at this point.
Now lets try to complete the loop by ssh-ing to your computer from within the docker container.
jenkins#e7b23bad10aa:/$ ssh user#172.17.0.1
This time you should not need to enter you password. If you do, something went wrong and you have to try again.
You will now be in your computers home folder. Try ls and have a look.
Do not stop here since we have a chain of ssh shells that we need to get out of.
$ exit
jenkins#e7b23bad10aa:/$ exit
Right! Now we are back and ready to continue.
Install your Jenkins
You will find your local Jenkins in your browser at http://localhost:8787.
First time you point your browser to your local Jenkins your will be greated with a Installation Wizard.
Defaults are fine, do make sure you install the pipeline plugin during the setup though.
Setup your jenkins
It is very important that you activate matrix based security on http://localhost:8787/configureSecurity and give yourself all rights by adding yourself to the matrix and tick all the boxes. (There is a tick-all-boxes icon on the far right)
Select Jenkins’ own user database as the Security Realm
Select Matrix-based security in the Authorization section
Write your username in the field User/group to add: and click on the [ Add ] button
In the table above your username should pop up with a people icon next to it. If it is crossed over you typed your username incorrectly.
Go to the far right of the table and click on the tick-all-button or manually tick all the boxes in your row.
Please verify that the checkbox Prevent Cross Site Request Forgery exploits is unchecked. (Since this Jenkins is only reachable from your computer this isn't such a big deal)
Click on [ Save ] and log out of Jenkins and in again just to make sure it works.
If it doesn't you have to start over from the beginning and emptying the /opt/docker/jenkins/jenkins_home folder before restarting
Add the git user
We need to allow our git hook to login to our local Jenkins with minimal rights. Just to see and build jobs is sufficient. Therefore we create a user called git with password login.
Direct your browser to http://localhost:8787/securityRealm/addUser and add git as username and login as password.
Click on [ Create User ].
Add the rights to the git user
Go to the http://localhost:8787/configureSecurity page in your browser. Add the git user to the matrix:
Write git in the field User/group to add: and click on [ Add ]
Now it is time to check the boxes for minimal rights to the git user. Only these are needed:
overall:read
job:build
job:discover
job:read
Make sure that the Prevent Cross Site Request Forgery exploits checkbox is unchecked and click on [ Save ]
Create the pipeline project
We assume we have the username user and our git enabled project with the Jenkinsfile in it is called project and is located at /home/user/projects/project
In your http://localhost:8787 Jenkins add a new pipeline project. I named it hookpipeline for reference.
Click on New Item in the Jenkins menu
Name the project hookpipeline
Click on Pipeline
Click [ OK ]
Tick the checkbox Poll SCM in the Build Triggers section. Leave the Schedule empty.
In the Pipeline section:
select Pipeline script from SCM
in the Repository URL field enter user#172.17.0.1:projects/project/.git
in the Script Path field enter Jenkinsfile
Save the hookpipeline project
Build the hookpipeline manually once, this is needed for the Poll SCM to start working.
Create the git hook
Go to the /home/user/projects/project/.git/hooks folder and create a file called post-commit that contains this:
#!/bin/sh
BRANCHNAME=$(git rev-parse --abbrev-ref HEAD)
MASTERBRANCH='master'
curl -XPOST -u git:login http://localhost:8787/job/hookpipeline/build
echo "Build triggered successfully on branch: $BRANCHNAME"
Make this file executable:
$ chmod +x /home/user/projects/project/.git/hooks/post-commit
Test the post-commit hook:
$ /home/user/projects/project/.git/hooks/post-commit
Check in Jenkins if your hookpipeline project was triggered.
Finally make some arbitrary change to your project, add the changes and do a commit. This will now trigger the pipeline in your local Jenkins.
Happy Days!
TL;DR
Jenkins Pipeline Unit testing framework
Jenkinsfile Runner
Long Version
Jenkins Pipeline testing becomes more and more of a pain. Unlike the classic declarative job configuration approach where the user was limited to what the UI exposed the new Jenkins Pipeline is a full fledged programming language for the build process where you mix the declarative part with your own code. As good developers we want to have some unit tests for this kind of code as well.
There are three steps you should follow when developing Jenkins Pipelines. The step 1. should cover 80% of the uses cases.
Do as much as possible in build scripts (eg. Maven, Gradle, Gulp etc.). Then in your pipeline scripts just calls the build tasks in the right order. The build pipeline just orchestrates and executes the build tasks but does not have any major logic that needs a special testing.
If the previous rule can't be fully applied then move over to Pipeline Shared libraries where you can develop and test custom logic on its own and integrate them into the pipeline.
If all of the above fails you, you can try one of those libraries that came up recently (March-2017). Jenkins Pipeline Unit testing framework or pipelineUnit (examples). Since 2018 there is also Jenkinsfile Runner, a package to execution Jenkins pipelines from a command line tool.
Examples
The pipelineUnit GitHub repo contains some Spock examples on how to use Jenkins Pipeline Unit testing framework
Jenkins has a 'Replay' feature, which enables you to quickly replay a job without updating sources:
At the moment of writing (end of July 2017) with the Blue Ocean plugin you can check the syntax of a declarative pipeline directly in the visual pipeline editor. The editor, works from the Blue Ocean UI when you click "configure" only for github projects (this is a known issue and they are working to make it work also on git etc).
But, as explained in this question you can open the editor browsing to:
[Jenkins URL]/blue/organizations/jenkins/pipeline-editor/
Then click in the middle of the page, and press Ctrl+S, this will open a textarea where you can paste a pipeline declarative script. When you click on Update, if there is a syntax error, the editor will let you know where the syntax error is. Like in this screenshot:
If there is no syntax error, the textarea will close and the page will visualize your pipeline. Don't worry it won't save anything (if it's a github project it would commit the Jenkinsfile change).
I'm new to Jenkins and this is quite helpful, without this I had to commit a Jenkinsfile many times, till it works (very annoying!). Hope this helps. Cheers.
A bit late to the party, but that's why I wrote jenny, a small reimplementation of some core Jenkinsfile steps. (https://github.com/bmustiata/jenny)
In my development setup – missing a proper Groovy editor – a great deal of Jenkinsfile issues originates from simple syntax errors. To tackle this issue, you can validate the Jenkinsfile against your Jenkins instance (running at $JENKINS_HTTP_URL):
curl -X POST -H $(curl '$JENKINS_HTTP_URL/crumbIssuer/api/xml?xpath=concat(//crumbRequestField,":",//crumb)') -F "jenkinsfile=<Jenkinsfile" $JENKINS_HTTP_URL/pipeline-model-converter/validate
The above command is a slightly modified version from
https://github.com/jenkinsci/pipeline-model-definition-plugin/wiki/Validating-(or-linting)-a-Declarative-Jenkinsfile-from-the-command-line
As far as i know this Pipeline Plugin is the "Engine" of the new Jenkinsfile mechanics, so im quite positive you could use this to locally test your scripts.
Im not sure if there is any additional steps needed when you copy it into a Jenkinsfile, however the syntax etc should be exactly the same.
Edit: Found the reference on the "engine", check this feature description, last paragraph, first entry.
For simplicity, you can create a Jenkinsfile at the root of the git repository, similar to the below example 'Jenkinsfile' based on the groovy syntax of the declarative pipeline.
pipeline {
agent any
stages {
stage('Build the Project') {
steps {
git 'https://github.com/jaikrgupta/CarthageAPI-1.0.git'
echo pwd()
sh 'ls -alrt'
sh 'pip install -r requirements.txt'
sh 'python app.py &'
echo "Build stage gets finished here"
}
}
stage('Test') {
steps {
sh 'chmod 777 ./scripts/test-script.sh'
sh './scripts/test-script.sh'
sh 'cat ./test-reports/test_script.log'
echo "Test stage gets finished here"
}
}
}
https://github.com/jaikrgupta/CarthageAPI-1.0.git
You can now set up a new item in Jenkins as a Pipeline job.
Select the Definition as Pipeline script from SCM and Git for the SCM option.
Paste the project's git repo link in the Repository URL and Jenkinsfile in the script name box.
Then click on the lightweight checkout option and save the project.
So whenever you pushed a commit to the git repo, you can always test the changes running the Build Now every time in Jenkins.
Please follow the instructions in the below visuals for easy setup a Jenkins Pipeline's job.
Aside from the Replay feature that others already mentioned (ditto on its usefulness!), I found the following to be useful as well:
Create a test Pipeline job where you can type in Pipeline code or point to your repo/branch of a Jenkinsfile to quickly test out something. For more accurate testing, use a Multibranch Pipeline that points to your own fork where you can quickly make changes and commit without affecting prod. Stuff like BRANCH_NAME env is only available in Multibranch.
Since Jenkinsfile is Groovy code, simply invoke it with "groovy Jenkinsfile" to validate basic syntax.
Put your SSH key into your Jenkins profile, then use the declarative linter as follows:
ssh jenkins.hostname.here declarative-linter < Jenkinsfile
This will do a static analysis on your Jenkinsfile. In the editor of your choice, define a keyboard shortcut that runs that command automatically. In Visual Studio Code, which is what I use, go to Tasks > Configure Tasks, then use the following JSON to create a Validate Jenkinsfile command:
{
"version": "2.0.0",
"tasks": [
{
"label": "Validate Jenkinsfile",
"type": "shell",
"command": "ssh jenkins.hostname declarative-linter < ${file}"
}
]
}
You can just validate your pipeline to find out syntax issues. Jenkins has nice API for Jenkisfile validation - https://jenkins_url/pipeline-model-converter/validate
Using curl and passing your .Jenkinsfile, you will get syntax check instantly
curl --user username:password -X POST -F "jenkinsfile=<jenkinsfile" https://jenkins_url/pipeline-model-converter/validate
You can add this workflow to editors:
VS Code
Sublime Text
Using the VS Code Jenkins Jack extension, you can have a way to test your Jenkinsfiles without use the git push way, from your local files to a local or remote running Jenkins. And you will have the running log of the job inside VS Code, the ability to create jobs in Jenkins and more staff. I hope this help to more people looking for a way to develop Jenkinsfiles.
i am using replay future , to do some update and run quickly .
With some limitations and for scripted pipelines I use this solution:
Pipeline job with an inlined groovy script:
node('master') {
stage('Run!') {
def script = load('...you job file...')
}
}
Jenkinsfile for testing have same structure as for lesfurets:
def execute() {
... main job code here ...
}
execute()
This is a short solution that lets me test Pipeline code very quickly:
pipeline {
agent any
options {
skipDefaultCheckout true
timestamps()
}
parameters {
text(name: 'SCRIPT', defaultValue: params.SCRIPT,
description: 'Groovy script')
}
stages {
stage("main") {
steps {
script {
writeFile file: 'script.groovy',
text: params.SCRIPT
def groovyScript = load 'script.groovy'
echo "Return value: " + groovyScript
}
} // steps
} // stage
} // stages
} // pipeline
skipDefaultCheckout true because we do not need the files in this tool git repository.
defaultValue: params.SCRIPT sets the default to the latest execution. If used by just one user, it allows for a very quick cycle of short tests.
The given script is written to a file, and loaded and with load.
With this setup I can test everything I can do inside my other Jenkinsfiles, including using shared libraries.

How to go about seeing the branch name of builds in the build history view of Jenkins?

I installed the Feature Branch Notifier Plugin in my instance of Jenkins.
I have checked the "Show full length branch name in the build history view" checkbox at jenkins:8080/configure
I am expecting to see the branch names in build history view, but even after restarting Jenkins I am not seeing the branch names in the build history, as can be seen in the enclosed image.
The project issue queue lists no open issues, and when I try to log in to post an issue, I get the message "Proxy Error - The proxy server received an invalid response from an upstream server. The proxy server could not handle the request POST /account/doSignup. Reason: Error reading from remote server Apache/2.2.14 (Ubuntu) Server at jenkins-ci.org Port 443"
Does anyone know how to go about seeing the branch name of builds in the build history view of Jenkins? Thanks!
Albert.
You can use Build Name Setter Plugin, and set Set Build Name something like #${BUILD_NUMBER} - ${GIT_BRANCH}.
Build-Name-setter-plugin no longer works. I tried on 2.319.1, and the setting never appears in the pipline.
The solution I found is to use the build environment variables to apply to your display name for the build in a step script.
Adjust your Jenkinsfile to pull the branch name as a environmental variable (I am using CURRENT_BRANCH_NAME). Then I created a new stage / step, that runs before any other, and ran a script to adjust the displayname there:
pipeline {
agent {any}
environment {
CURRENT_BRANCH_NAME = "${GIT_BRANCH.split('/').size() > 1 ? GIT_BRANCH.split('/')[1..-1].join('/') : GIT_BRANCH}"
}
stages {
stage('Set branch name') {
steps {
script{
currentBuild.displayName = "#"+currentBuild.number+": "+CURRENT_BRANCH_NAME
}
}
}
stages {
stage('Ok now start doing testing') {
steps {
sh '''#!/bin/bash
echo "Im gona test everything"
'''
}
}
}
}
Now when your Jenkins test starts to build, the name will update once the step is complete.
Note: this solution was tested in a single pipeline (not multi-pipeline), and was for a SCM repo integration.
Sources:
Get git branch name in Jenkins Pipeline/Jenkinsfile
https://sleeplessbeastie.eu/2021/01/29/how-to-define-build-name-and-description-in-jenkins/

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