Can't read a file parm in jenkins pipeline - jenkins-pipeline

example :
pipeline{
agent any
stages{
stage('Parse CSV'){
steps {
script{
def fileToParse = readFile(params.FileLocation)
}
echo fileToParse
}
}
}
}
I configured the job from the GUI, the file location parameter is called FileLocation. I uploaded a file and tried to read it. When I try to access params.FileLocation it returns null, as if it doesn't recognise it.

Your problem is with the variable scope. You def the variable in the script {} block scope, then try to use it outside of it. One easy fix is to def the variable outside the pipeline {} block at the global level. Or, just use the params.FileLocation in your echo statement.
def fileToParse
pipeline{
agent any
stages{
stage('Parse CSV'){
steps {
script{
fileToParse = readFile(params.FileLocation)
}
echo fileToParse
echo params.FileLocation
}
}
}
}

file param is not supported and it is removed from documentation as well.
https://issues.jenkins-ci.org/browse/JENKINS-27413
Check available parameters: https://jenkins.io/doc/book/pipeline/syntax/#parameters

Related

Jenkins function of shared library executed on wrong node

I have a simple shared library and want to call a function which creates a file.
My pipeline script looks like this:
#Library('jenkins-shared-library')_
pipeline {
agent {
node {
label 'node1'
}
}
stages {
stage('test') {
steps {
script {
def host = sh(script: 'hostname', returnStdout: true).trim()
echo "Hostname is: ${host}"
def testlib = new TestLibrary(script:this)
testlib.createFile("/tmp/file1")
}
}
}
}
}
This pipeline job is triggered by another job which runs on the built-in master node.
The stage 'test' is correctly executed on the 'node1'.
Problem: The created file "/tmp/file1" is created on the jenkins master, instead of "node1"
I also tried it without the shared library and load a groovy script
directly in a step:
pipeline {
agent {
node {
label 'node1'
}
}
stages {
stage('test') {
steps {
script {
def script = load "/path/to/script.groovy"
script.createFile("/tmp/file1")
}
}
}
}
}
This also creates the file on the master node, instead on "node1".
Is there no way of loading external libs or classes and execute them on the node where the stage is running on ? I dont want to place all the code directly into the step.
Ok I found it myself, groovy scripts run by definition always on the master node. No way to run scripts or shared-library code on a node other than master.

Assigning values to Jenkins environment variables is not working

I declared the environment variables in pipeline syntax and I'm trying to assign values to the variables by reading the file from workspace. Assigned values are not reflected in environment variable. my configuration looks like below
pipeline {
agent any
environment {
test = ''
}
stages {
stage('Test') {
script {
writeFile(file: 'hello.txt', text: "hello world")
env.test = readFile(file: 'hello.txt')
echo 'test:'"${env.test}" // coming as null
}
}
}
}
}
Try to remove test from environment block.
Also, you have a problem with '' and "" when you display env.test, try to do this:
echo "test: ${env.test}" // coming as null

Jenkins declarative pipeline get environment variable at post stage

I am getting runtime value in build stage stage which I stored in an environment variable . I saved that to env.cfg file under WORKSPACE .
Now I am trying to get that value in post pipeline step to be used in email communication. I tried load method but it did not work
Any help ?
post {
always {
echo $SNAPSHOT / /this always comes null
}
}
This is the way you can access an environment variable across the pipeline
pipeline {
agent any;
environment {
MESSAGE="Hello World"
}
stages {
stage('one') {
steps {
echo "${env.MESSAGE}"
sh "echo $MESSAGE"
script {
print env.MESSAGE
}
}
}
}
post {
success {
echo "${env.MESSAGE}"
script {
print env.MESSAGE
}
}
failure {
echo "${env.MESSAGE}"
script {
print env.MESSAGE
}
}
}
}
but as per your scenario let say I have a file called .env with the content below in the current Jenkins job WORKSPACE and I want to read and make this env variable in the pipeline.
.env
export SNAPSHOT=1.0.0
export MESSAGE='Hello World'
export MESSAGE_FROM_ENV_FILE='Hello From .env file'
your pipeline should look like
scripted pipeline
node {
stage('one') {
sh """
source $WORKSPACE/.env
echo \$SNAPSHOT
echo \$MESSAGE
echo \$MESSAGE_FROM_ENV_FILE
"""
}
}
declarative pipeline
pipeline {
agent any;
stages {
stage('build') {
steps {
sh """
source $WORKSPACE/.env
echo \$SNAPSHOT
echo \$MESSAGE
echo \$MESSAGE_FROM_ENV_FILE
"""
}
}
}
post {
success {
sh """
source $WORKSPACE/.env
echo \$SNAPSHOT
echo \$MESSAGE
echo \$MESSAGE_FROM_ENV_FILE
"""
}
}
}
You need a global variable:
SNAPSHOT = ""
println "SNAPSHOT is ${SNAPSHOT}"
pipeline {
agent any
stages {
stage('Build') {
steps {
script {
println "SNAPSHOT is ${SNAPSHOT}"
SNAPSHOT = "Modified"
println "SNAPSHOT is now ${SNAPSHOT}"
}
}
}
}
post {
always {
echo "${SNAPSHOT}"
}
}
}

Fetch credentials depending on environment

I can take credentials like explained in the example taken from here - https://jenkins.io/doc/book/pipeline/syntax/#environment
stage('Example') {
environment {
CREDS = credentials('MY_CREDS_DEV')
}
steps {
sh 'echo hello'
}
}
But what I want to do is to get credentials based on some condition.
For example I have MY_CREDS_DEV and MY_CREDS_QA defined in Jenkins credentials. And I have a property ENV=dev defined in Jenkins 'Prepare an environment for the run' section.
I'd like to access credentials based on my environment, i.e. ENV property.
I tried to use CREDS = credentials('MY_CREDS_' + ${ENV}) and tried to extract strings concatenation to a separate function and call it like CREDS = credentials(concatenate(${ENV})) but I got Internal function call parameters must be strings.
So seems I can put only a string to credentials() function which basically means to hardcode it. But how can I choose which credentials to use - dev or qa?
Use CREDS = credentials('MY_CREDS_' + ENV) or CREDS = credentials("MY_CREDS_${ENV}"). ${ENV} will not become 'dev'but ${'dev'} and therefore is no string.
For completeness:
In fact - after playing aroung with the groovy console - it looks like ${ENV} will try to call a function called $ with the closure parameter {ENV} which in turn would return 'dev'. It would give the same result as ENV if you would have defined a function like:
def $(Closure closure) {
closure()
}
But most probably that's not what you wanted to do.
Got this working in Jenkins:2.190.2 with a little groovy. Haven't tested on earlier versions. Just happens to be the one I'm on now. Works fine with multiple stages.
pipeline {
agent {
label "xxxxx"
}
environment {
ROLE = getRole()
}
stages{
stage("write to s3 etc") {
environment {
AWS = credentials("${ROLE}")
}
steps {
script {
sh"""
aws s3 sync build/ "s3://xxxxxxxxxxxx"
"""
}
}
}
}
}
def getRole() {
def branchName = "${env.BRANCH_NAME}"
if (branchName == "xxxxxx") {
return 'some_credential_string'
}
else {
return 'some_other_credential_string'
}
}
If you would like to use different credentials based on the condition, this could be done with the following example:
stage ("Example") {
steps {
script {
if ( params.TEST_PARAMETER == "test_value1" ) {
withCredentials([string(credentialsId: env.CREDENTIALS_1, variable: 'SOME_VARIABLE')]) {
yourFunction()
}
}
else {
withCredentials([string(credentialsId: env.CREDENTIALS_2, variable: 'SOME_VARIABLE')]) {
yourFunction()
}
}
}
}
}
You would need to define yourFunction in the end of your jenkinsfile. In this case, when TEST_PARAMETER is test_value1 in the job, CREDENTIALS_1 will be used from Jenkins credentials list. When TEST_PARAMETER is different, CREDENTIALS_2 credentials will be used. You could have more options by modifying this to the case loop.
Hope this helps.

How to define and call custom methods in build.gradle?

As part of my project, I need to read files from a directory and do some operations all these in build script. For each file, the operation is the same(reading some SQL queries and execute it). I think its a repetitive task and better to write inside a method. Since I'm new to Gradle, I don't know how it should be. Please help.
One approach given below:
ext.myMethod = { param1, param2 ->
// Method body here
}
Note that this gets created for the project scope, ie. globally available for the project, which can be invoked as follows anywhere in the build script using myMethod(p1, p2) which is equivalent to project.myMethod(p1, p2)
The method can be defined under different scopes as well, such as within tasks:
task myTask {
ext.myMethod = { param1, param2 ->
// Method body here
}
doLast {
myMethod(p1, p2) // This will resolve 'myMethod' defined in task
}
}
If you have defined any methods in any other file *.gradle - ext.method() makes it accessible project wide. For example here is a
versioning.gradle
// ext makes method callable project wide
ext.getVersionName = { ->
try {
def branchout = new ByteArrayOutputStream()
exec {
commandLine 'git', 'rev-parse', '--abbrev-ref', 'HEAD'
standardOutput = branchout
}
def branch = branchout.toString().trim()
if (branch.equals("master")) {
def stdout = new ByteArrayOutputStream()
exec {
commandLine 'git', 'describe', '--tags'
standardOutput = stdout
}
return stdout.toString().trim()
} else {
return branch;
}
}
catch (ignored) {
return null;
}
}
build.gradle
task showVersion << {
// Use inherited method
println 'VersionName: ' + getVersionName()
}
Without ext.method() format , the method will only be available within the *.gradle file it is declared. This is the same with properties.
You can define methods in the following way:
// Define an extra property
ext.srcDirName = 'src/java'
// Define a method
def getSrcDir(project) {
return project.file(srcDirName)
}
You can find more details in gradle documentation Chapter 62. Organizing Build Logic
An example with a root object containing methods.
hg.gradle file:
ext.hg = [
cloneOrPull: { source, dest, branch ->
if (!dest.isDirectory())
hg.clone(source, dest, branch)
else
hg.pull(dest)
hg.update(dest, branch)
},
clone: { source, dest, branch ->
dest.mkdirs()
exec {
commandLine 'hg', 'clone', '--noupdate', source, dest.absolutePath
}
},
pull: { dest ->
exec {
workingDir dest.absolutePath
commandLine 'hg', 'pull'
}
},
]
build.gradle file
apply from: 'hg.gradle'
hg.clone('path/to/repo')
Somehow, maybe because it's five years since the OP, but none of the
ext.someMethod = { foo ->
methodBody
}
approaches are working for me. Instead, a simple function definition seems to be getting the job done in my gradle file:
def retrieveEnvvar(String envvar_name) {
if ( System.getenv(envvar_name) == "" ) {
throw new InvalidUserDataException("\n\n\nPlease specify environment variable ${envvar_name}\n")
} else {
return System.getenv(envvar_name)
}
}
And I call it elsewhere in my script with no prefix, ie retrieveEnvvar("APP_PASSWORD")
This is 2020 so I'm using Gradle 6.1.1.
#ether_joe the top-voted answer by #InvisibleArrow above does work however you must define the method you call before you call it - i.e. earlier in the build.gradle file.
You can see an example here. I have used this approach with Gradle 6.5 and it works.
With Kotlin DSL (build.gradle.kts) you can define regular functions and use them.
It doesn't matter whether you define your function before the call site or after it.
println(generateString())
fun generateString(): String {
return "Black Forest"
}
tasks.create("MyTask") {
println(generateString())
}
If you want to import and use a function from another script, see this answer and this answer.
In my react-native in build.gradle
def func_abc(y){return "abc"+y;}
then
def x = func_abc("y");
If you want to check:
throw new GradleException("x="+x);
or
println "x="+x;

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