How to use Jenkins Node Environment Variables in a Pipeline script? - jenkins

In the Jenkins --> Manage Jenkins --> Manage Nodes --> Configure Node, under Node Properties, you can configure Environment Variables for the Node.
Is there a way to use them in a Pipeline Script?
Now I have to do something like
...
environment {
GITMIRRORS='/home/jenkins/git-mirrors'
DLC117='/progress/117_64/dlc'
}
...
As a result, I'll have those paths in a lot of Pipeline scripts. But they are defined on the Node...
Is there a way to say 'use that agent' and 'use its env variables from the main Jenkins Node configuration'?
If not, is there way to say GITMIRRORS=GetNodeEnvVariable('...', '...')

Yes, you can use them in the following ways:
echo"${GITMIRRORS}"
or you can use it in your code as:
gitMirrors = env.GITMIRRORS

How to use Jenkins Node Environment Variables in a Pipeline script?
Jenkins issue (dated back from 2017-05...)
If you can afford the change :
move any conflicting definition of the envvar from the global setup to all the node setups
or load a script or define the adequate variable value in the Jenkinsfile
references :
https://issues.jenkins-ci.org/browse/JENKINS-44425
https://issues.jenkins-ci.org/browse/JENKINS-44465

I did not find a way to do it with pure Groovy. But you can execute a command on the node and capture its output in a script block:
def GITMIRRORS = bat(script: "#echo %GITMIRRORS%", returnStdout: true).trim()
on Windows agent or
def GITMIRRORS = sh(script: "echo ${GITMIRRORS}", returnStdout: true).trim()
on Linux agent.

Related

How to retrieve Jenkins environment from Groovy script?

I am setting a Jenkins. I am programming with my pipeline using Global Pipeline Libraries to be able to increase reusability. Scripts are object oriented and in Groovy. Information about the concept can be found there
I don't manage to retrieve the Jenkins specific environment using my library script. I would like for instance to access:
Build_ID
Build_Number
JOB_Name
Workspace_path
I tryied to use env.WORKSPACE but it is returning a NULL. I manage to retrieve it directly in the pipeline but this is not my goal.
I am using Jenkins 2.303.1.
Depending on how you write your scripts, you might need to inject the Jenkins environment. For example, if you go for a more object oriented way
// vars/whatever.groovy
import ...
#Field
def myTool = new MyTool(this)
// src/.../MyTool.groovy
import ...
class MyTool {
private final jenkins
MyTool(steps) {
this.jenkins = jenkins
}
def echoBuildNumber() {
this.jenkins.echo(this.jenkins.env.BUILD_NUMBER)
}
}
// Jenkinsfile
#Library(...)
node {
echo env.BUILD_NUMBER // echoes build number
whatever.myTool.echoBuildNumber() // echoes build number
}
So the env which you are looking for can be accessible using like this in groovy script
${env.BUILD_NUMBER}
${env.JOB_NAME}
${env.WORKSPACE}
${env.BUILD_ID}

Running a groovy script through jenkinsfile which runs on a remote linux box

I have a abc.groovy script which takes an argument. In my local I run it as
$ groovy abc.groovy <argumentValue>
I have stored this abc.groovy in a remote linux box under path "/home/path/to a directory/" and I have a jenkins pipeline job with a Jenkinsfile. How can I call abc.groovy from the JenkinsFile.
You can use GroovyShell to evaluate your script.
GroovyShell shell = new GroovyShell()
def execute = shell.parse(new File('/path/to/abc.groovy'))
execute.method()
You'll want to use the load step in your Jenkinsfile like this:
def pipeline {
agent 'slave'
stages {
stage ('Load Groovy Script') {
steps {
load 'path/to/abc.groovy'
}
}
}
(This example uses the declarative pipeline syntax, but is easily ported to scripted)
Note: you can't pass parameters to the groovy script in the load step, however this isn't hard to work around.

Environment variable in Jenkins Pipeline

Is there any environment variable available for getting the Jenkins Pipeline Title?
I know we can use $JOB_NAME to get title for a freestyle job,
but is there anything that can be used for getting Pipeline name?
You can access the same environment variables from groovy using the same names (e.g. JOB_NAME or env.JOB_NAME).
From the documentation:
Environment variables are accessible from Groovy code as env.VARNAME or simply as VARNAME. You can write to such properties as well (only using the env. prefix):
env.MYTOOL_VERSION = '1.33'
node {
sh '/usr/local/mytool-$MYTOOL_VERSION/bin/start'
}
These definitions will also be available via the REST API during the build or after its completion, and from upstream Pipeline builds using the build step.
For the rest of the documentation, click the "Pipeline Syntax" link from any Pipeline job
To avoid problems of side effects after changing env, especially using multiple nodes, it is better to set a temporary context.
One safe way to alter the environment is:
withEnv(['MYTOOL_HOME=/usr/local/mytool']) {
sh '$MYTOOL_HOME/bin/start'
}
This approach does not poison the env after the command execution.

Need to get jenkins build number

In my Jenkins job configure section I am calling an expect script to run.I need to get the current build number value in a variable in the expect script. is it possible to get the build number in a variable?
example. in my Jenkins job i am calling an expect script sample_text.exp in which i need to get current build number in a variable Build_no
is it possible?
yes, it is possible. There is environment variable BUILD_NUMBER. What you mean by "Jenkins job configure section"? In "Execute Windows batch command" in (build section) you can do:
echo %BUILD_NUMBER%
to get this number in a different variable:
set "BUILD_NO=%BUILD_NUMBER%"
echo %BUILD_NO%
Very much possible. You can use the environment variable, BUILD_NUMBER for that in execute shell section. To get a list of all the environment variables that one can use, go to
<your_jenkins_url>/env-vars.html
For example:
http://my-jenkins-box:8080/env-vars.html
Logic that I spoke off in my below comment
if [ -z ${JOB_URL} ]; then
echo "*************************** This is not a Jenkins build ***********"
# Do your stuff here :)
else
echo "**************************** This is a jenkins build so maven project is built before this script is executed via Jenkins ***************************"
fi
Also, remember that if you are running your script with sudo, these environment variables will not be available then

How to set environment variables in Jenkins?

I would like to be able to do something like:
AOEU=$(echo aoeu)
and have Jenkins set AOEU=aoeu.
The Environment Variables section in Jenkins doesn't do that. Instead, it sets AOEU='$(echo aoeu)'.
How can I get Jenkins to evaluate a shell command and assign the output to an environment variable?
Eventually, I want to be able to assign the executor of a job to an environment variable that can be passed into or used by other scripts.
This can be done via EnvInject plugin in the following way:
Create an "Execute shell" build step that runs:
echo AOEU=$(echo aoeu) > propsfile
Create an Inject environment variables build step and set "Properties File Path" to propsfile.
Note: This plugin is (mostly) not compatible with the Pipeline plugin.
The simplest way
You can use EnvInject plugin to injects environment variables at build startup. For example:
How you know it's working
In my case, I needed to add the JMETER_HOME environment variable to be available via my Ant build scripts across all projects on my Jenkins server (Linux), in a way that would not interfere with my local build environment (Windows and Mac) in the build.xml script. Setting the environment variable via Manage Jenkins - Configure System - Global properties was the easiest and least intrusive way to accomplish this. No plug-ins are necessary.
The environment variable is then available in Ant via:
<property environment="env" />
<property name="jmeter.home" value="${env.JMETER_HOME}" />
This can be verified to works by adding:
<echo message="JMeter Home: ${jmeter.home}"/>
Which produces:
JMeter Home: ~/.jmeter
In my case, I had configure environment variables using the following option and it worked-
Manage Jenkins -> Configure System -> Global Properties -> Environment Variables -> Add
You can try something like this
stages {
stage('Build') {
environment {
AOEU= sh (returnStdout: true, script: 'echo aoeu').trim()
}
steps {
sh 'env'
sh 'echo $AOEU'
}
}
}
You can use Environment Injector Plugin to set environment variables in Jenkins at job and node levels. These are the steps to set them at job level:
From the Jenkins web interface, go to Manage Jenkins > Manage Plugins and install the plugin.
Go to your job Configure screen
Find Add build step in Build section and select Inject environment variables
Set the desired environment variable as VARIABLE_NAME=VALUE pattern. In my case, I changed value of USERPROFILE variable
If you need to define a new environment variable depending on some conditions (e.g. job parameters), then you can refer to this answer.
EnvInject Plugin aka (Environment Injector Plugin) gives you several options to set environment variables from Jenkins configuration.
By selecting Inject environment variables to the build process you will get:
Properties File Path
Properties Content
Script File Path
Script Content
and finally Evaluated Groovy script.
Evaluated Groovy script gives you possibility to set environment variable based on result of executed command:
with execute method:
return [HOSTNAME_SHELL: 'hostname'.execute().text,
DATE_SHELL: 'date'.execute().text,
ECHO_SHELL: 'echo hello world!'.execute().text
]
or with explicit Groovy code:
return [HOSTNAME_GROOVY: java.net.InetAddress.getLocalHost().getHostName(),
DATE_GROOVY: new Date()
]
(More details about each method could be found in build-in help (?))
Unfortunately you can't do the same from Script Content as it states:
Execute a script file aimed at setting an environment such as creating
folders, copying files, and so on. Give the script file content. You
can use the above properties variables. However, adding or overriding
environment variables in the script doesn't have any impacts in the
build job.
There is Build Env Propagator Plugin which lets you add new build environment variables, e.g.
Any successive Propagate build environment variables step will override previously defined environment variable values.
Normally you can configure Environment variables in Global properties in Configure System.
However for dynamic variables with shell substitution, you may want to create a script file in Jenkins HOME dir and execute it during the build. The SSH access is required. For example.
Log-in as Jenkins: sudo su - jenkins or sudo su - jenkins -s /bin/bash
Create a shell script, e.g.:
echo 'export VM_NAME="$JOB_NAME"' > ~/load_env.sh
echo "export AOEU=$(echo aoeu)" >> ~/load_env.sh
chmod 750 ~/load_env.sh
In Jenkins Build (Execute shell), invoke the script and its variables before anything else, e.g.
source ~/load_env.sh
This is the snippet to store environment variable and access it.
node {
withEnv(["ENABLE_TESTS=true", "DISABLE_SQL=false"]) {
stage('Select Jenkinsfile') {
echo "Enable test?: ${env.DEVOPS_SKIP_TESTS}
customStep script: this
}
}
}
Note: The value of environment variable is coming as a String. If you want to use it as a boolean then you have to parse it using Boolean.parse(env.DISABLE_SQL).
extending the answer of #JSixface:
To define environment variables globally for access from within all the stages of a declarative pipeline, you can add the environment section within the pipeline block.
pipeline {
agent {
node {
label 'myAgent'
}
}
environment {
AOEU = "${sh(returnStdout: true, script: 'echo aoeu').trim()}"
}
stages {
...
}
}
Try Environment Script Plugin (GitHub) which is very similar to EnvInject. It allows you to run a script before the build (after SCM checkout) that generates environment variables for it. E.g.
and in your script, you can print e.g. FOO=bar to the standard output to set that variable.
Example to append to an existing PATH-style variable:
echo PATH+unique_identifier=/usr/local/bin
So you're free to do whatever you need in the script - either cat a file, or run a script in some other language from your project's source tree, etc.
For some reason sudo su - jenkins does not log me to jenkins user, I ended up using different approach.
I was successful setting the global env variables using using jenkins config.xml at /var/lib/jenkins/config.xml (installed in Linux/ RHEL) - without using external plugins.
I simply had to stop jenkins add then add globalNodeProperties, and then restart.
Example, I'm defining variables APPLICATION_ENVIRONMENT and SPRING_PROFILES_ACTIVE to continious_integration below,
<?xml version='1.0' encoding='UTF-8'?>
<hudson>
<globalNodeProperties>
<hudson.slaves.EnvironmentVariablesNodeProperty>
<envVars serialization="custom">
<unserializable-parents/>
<tree-map>
<default>
<comparator class="hudson.util.CaseInsensitiveComparator"/>
</default>
<int>2</int>
<string>APPLICATION_ENVIRONMENT</string>
<string>continious_integration</string>
<string>SPRING_PROFILES_ACTIVE</string>
<string>continious_integration</string>
</tree-map>
</envVars>
</hudson.slaves.EnvironmentVariablesNodeProperty>
</globalNodeProperties>
</hudson>
You can use either of the following ways listed below:
Use Env Inject Plugin for creating environment variables. Follow this for usage and more details https://github.com/jenkinsci/envinject-plugin
Navigate below and can add
Manage Jenkins -> Configure System -> Global Properties -> Environment Variables -> Add
Scripted Pipeline syntax that we use is this:
env.AEOU = sh label:'set env var',
returnStdout: true,
script : '''#!/bin/bash
echo "aeou"
'''
sh label:'checkit',
script : '''#!/bin/bash
echo "${AEOU}"
'''
Note the use of triple-single-quote notation for the script parameter to the sh step. This ensures that the ${AEOU} does not get interpolated by Groovy and does get interpolated by the bash shell.
We use groovy job file:
description('')
steps {
environmentVariables {
envs(PUPPETEER_SKIP_CHROMIUM_DOWNLOAD: true)
}
}

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