jenkinsfile setting environment variable with substring extraction - jenkins

Having trouble attempting to set a environment variable that uses substring extraction of another environment variable.
pipeline {
agent any
environment {
NODE_BASE_NAME = "ui-node-${GIT_COMMIT:0:6}"
}
stages {
stage ("test") {
steps {
echo "${NODE_BASE_NAME}"
}
}
}
}
Results in
WorkflowScript: 4: expecting '}', found ':' # line 4, column 49.
NAME = "ui-node-${GIT_COMMIT:0:6}"

The intrinsic method for doing a substring in Groovy is String substring(int beginIndex, int endIndex). Therefore, the correct syntax for interpolating your string assigned to NODE_BASE_NAME with a GIT_COMMIT substring is:
environment {
NODE_BASE_NAME = "ui-node-${GIT_COMMIT.substring(0, 6)}"
}

Related

How to convert a jenkins boolean param into all caps "TRUE" or "FALSE" string parameter?

I have the following defined in my multibranch declarative pipeline:
steps {
script {
BUILD_PROD_FLAG = sh(returnStdout: true, script: "[ ${BUILD_PROD} = true ] && echo TRUE || echo FALSE; ").trim()
BUILD_PROD_FLAG_SECOND = expression { if (params.BUILD_PROD) { return "TRUE" } else { return "FALSE" } }
}
sh "echo alternative way to get true/false set (want this to say FALSE): ${BUILD_FLAG_SECOND}"
}
The first variable BUILD_PROD_FLAG works fine.
I would like to eliminate the convoluted bash spawning employed there.
The second one does not work:
Multibranch_PR-1#tmp/durable-212f3652/script.sh: 1: /home/ubuntu/workspace/s_InsightCamera_Multibranch_PR-1#tmp/durable-212f3652/script.sh: Syntax error: "(" unexpected
This apparently is due to
Which I am not able to comprehend.
When the expression block is removed it fails to parse:
org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
WorkflowScript: 67: unexpected token: if # line 67, column 57.
BUILD_FLAG_SECOND = if (params
^
1 error
And when I tried something else that is different:
BUILD_FLAG_SECOND = expression { return params.BUILD_PROD ? "TRUE" : "FALSE" }
I get the same Syntax error: "(" unexpected error. I don't understand why this is a .sh shell script, by the way.
Update: OK I think I get why it's a .sh, that's just the sh clause near the bottom that I have.
I also thought I solved it because I did neglect to quote things for the shell, but with the adjustment:
sh "echo 'alternative way to get true/false set (want this to say FALSE):' ${BUILD_FLAG_SECOND}"
Still the same error:
I think it is for real trying to interpolate the string #expression(<anonymous>=org.jenkinsci.plugins.workflow.cps.CpsClosure2#4a286654) in place of the BUILD_FLAG_SECOND variable...
Are you ready for the epic facepalm that is the solution?
BUILD_FLAG_SECOND = params.BUILD_PROD ? "TRUE" : "FALSE"
That's it.

Test if there is a match when using regular expression in jenkins pipeline

I am using regex to grab a number from a string in my pipeline
it works ok as long that I have a match, but when there is no match I get an error
java.lang.IndexOutOfBoundsException: index is out of range 0..-1 (index = 0)
There error happens when i try to capture the group on following line
env.ChangeNr = chngnr[0][1]
How can i test if there isn't a match from my capture group ?
This is the pipeline
pipeline {
agent {
node {
label 'myApplicationNode'
}
}
environment {
GIT_MESSAGE = "${bat(script: "git log --no-walk --format=format:%%s ${GIT_COMMIT}", returnStdout: true)}".readLines().drop(2).join(" ")
}
stages {
stage('get_commit_msg'){
steps {
script {
def gitmsg=env.GIT_MESSAGE
def chngnr = gitmsg =~/([0-9]{1,8})/
env.ChangeNr = chngnr[0][1] /* put test if nothing is extracted */
}
}
}
}
}
In groovy when you use the =~ (find operator) it actually creates a java.util.regex.Matcher and therefore you can use any of its standard methods like find() or size(), so in your case you can jest use the size function to test if there are any matched patterns before you attempt to extract any groups:
def chngnr = gitmsg =~/([0-9]{1,8})/
assert chngnr.size() > 0
env.ChangeNr = chngnr[0][1]
Another nice option is to use the =~ operator in context of boolean, in this case, Groovy implicitly invokes the matcher.find() method, which means that the expression evaluates to true if any part of the string matches the pattern:
def chngnr = gitmsg =~/([0-9]{1,8})/
if(chngnr){
env.ChangeNr = chngnr[0][1]
}
else {
...
}
You can read more info on Groovy Regular Expressions Here

Groovy multiline string interpolation whitespace

I am trying to generate some generic Groovy code for Jenkins but I seem to have trouble with multi line strings and extra white space. I've tried everything I could find by Googling but I can't seem to get it working.
My issue isn't related to simple multi line strings. I managed to trim white space by using the stripIndent() and stripMargin() methods for simple cases. My issue is caused by having interpolated methods inside my strings.
Groovy info: Groovy Version: 3.0.2 JVM: 13.0.2 Vendor: Oracle Corporation OS: Mac OS X
String method2(String tier, String jobName) {
return """
Map downstreamJobs = [:]
stage ("${jobName}-${tier}-\${region}_${jobName}") {
test
}
""".stripIndent().stripMargin()
}
static String simpleLog() {
return """
script {
def user = env.BUILD_USER_ID
}
""".stripIndent().stripMargin()
}
static String method1() {
return """\
import jenkins.model.Jenkins
currentBuild.displayName = "name"
${simpleLog()}
""".stripIndent().stripMargin()
}
String generateFullDeploymentPipelineCode() {
return """Text here
${method1()}
${method2("test1", "test2")}
""".stripIndent().stripMargin()
}
println(generateFullDeploymentPipelineCode())
This is what it prints(or writes to disk):
Text here
import jenkins.model.Jenkins
currentBuild.displayName = "name"
script {
def user = env.BUILD_USER_ID
}
Map downstreamJobs = [:]
stage ("test2-test1-${region}_test2") {
test
}
Why the extra space around the import lines? I know the indentation method is supposed to trim all white space according to the least number of leading spaces, so that's why we use backslash (example here https://stackoverflow.com/a/19882917/7569335).
That works for simple strings, but it breaks down once use start using interpolation. Not with regular variables, just when you interpolate an entire method.
as variant - use just stripMargin() and only once on a final string
String method2(String tier, String jobName) {
return """\
|Map downstreamJobs = [:]
|stage ("${jobName}-${tier}-\${region}_${jobName}") {
| test
|}
"""
}
static String simpleLog() {
return """\
|script {
| def user = env.BUILD_USER_ID
|}
"""
}
static String method1() {
return """\
|import jenkins.model.Jenkins
|currentBuild.displayName = "name"
${simpleLog()}
"""
}
String generateFullDeploymentPipelineCode() {
return """\
|Text here
${method1()}
${method2("test1", "test2")}
""".stripIndent().stripMargin()
}
println(generateFullDeploymentPipelineCode())
result:
Text here
import jenkins.model.Jenkins
currentBuild.displayName = "name"
script {
def user = env.BUILD_USER_ID
}
Map downstreamJobs = [:]
stage ("test2-test1-${region}_test2") {
test
}
another variant with trim() and stripIndent()
def method2(String tier, String jobName) {
return """
Map downstreamJobs = [:]
stage ("${jobName}-${tier}-\${region}_${jobName}") {
test
}
""".trim()
}
def simpleLog() {
return """
script {
def user = env.BUILD_USER_ID
}
""".trim()
}
def method1() {
return """
import jenkins.model.Jenkins
currentBuild.displayName = "name"
${simpleLog()}
""".trim()
}
def generateFullDeploymentPipelineCode() {
return """\
Text here
${method1()}
${method2("test1", "test2")}
""".stripIndent()
}
println(generateFullDeploymentPipelineCode())
When you insert a string through interpolation you only indent the first line of it. The following lines of the inserted string will be indented differently, which messes everything up.
Using some lesser-known members of GString (namely .strings[] and .values[]), we can align the indentation of all lines of each interpolated value.
String method2(String tier, String jobName) {
indented """
Map downstreamJobs = [:]
stage ("${jobName}-${tier}-\${region}_${jobName}") {
test
}
"""
}
String simpleLog() {
indented """\
script {
def user = env.BUILD_USER_ID
}
"""
}
String method1() {
indented """\
import jenkins.model.Jenkins
currentBuild.displayName = "name"
${simpleLog()}
"""
}
String generateFullDeploymentPipelineCode() {
indented """\
Text here
${method1()}
${method2("test1", "test2")}
"""
}
println generateFullDeploymentPipelineCode()
//---------- Move the following code into its own script ----------
// Function to adjust the indentation of interpolated values so that all lines
// of a value match the indentation of the first line.
// Finally stripIndent() will be called before returning the string.
String indented( GString templ ) {
// Iterate over the interpolated values of the GString template.
templ.values.eachWithIndex{ value, i ->
// Get the string preceding the current value. Always defined, even
// when the value is at the beginning of the template.
def beforeValue = templ.strings[ i ]
// RegEx to match any indent substring before the value.
// Special case for the first string, which doesn't necessarily contain '\n'.
def regexIndent = i == 0
? /(?:^|\n)([ \t]+)$/
: /\n([ \t]+)$/
def matchIndent = ( beforeValue =~ regexIndent )
if( matchIndent ) {
def indent = matchIndent[ 0 ][ 1 ]
def lines = value.readLines()
def linesNew = [ lines.head() ] // The 1st line is already indented.
// Insert the indentation from the 1st line into all subsequent lines.
linesNew += lines.tail().collect{ indent + it }
// Finally replace the value with the reformatted lines.
templ.values[ i ] = linesNew.join('\n')
}
}
return templ.stripIndent()
}
// Fallback in case the input string is not a GString (when it doesn't contain expressions)
String indented( String templ ) {
return templ.stripIndent()
}
Live Demo at codingground
Output:
Text here
import jenkins.model.Jenkins
currentBuild.displayName = "name"
script {
def user = env.BUILD_USER_ID
}
Map downstreamJobs = [:]
stage ("test2-test1-${region}_test2") {
test
}
Conclusion:
Using the indented function, a clean Groovy syntax for generating code from GString templates has been achieved.
This was quite a learning experience. I first tried to do it completely different using the evaluate function, which turned out to be too complicated and not so flexible. Then I randomly browsed through some posts from mrhaki blog (always a good read!) until I discovered "Groovy Goodness: Get to Know More About a GString". This was the key to implementing this solution.

Checking for null pointer exception in an array in Jenkins scripted pipeline method

I am injecting Active Choices parameter value(s) in the Jenkins scripted pipeline.
PFB sample values passed to active choice parameter block:
return['ABC','DEF','GHI',JKL']
PFB my sample script:
node(){
selectModName()
}
def selectModName(){
stage 'Multi selection'
String[] mods = "${modName}".split(',')
modsz = mods.size()
echo ''+modsz+''
for(mod in mods){
if (modsz == null || modsz == 0){
echo 'There is nothing to be printed'
} else {
echo ''+mod+' is name of the module \n'
}
}
}
The else block is executed when I pass greater than or equal to 1 value(s) (working as intended). But if block is not executing its logic when I don't pass any parameter and press build now.
Funny thing is- size() is returning 1 instead of 0 (echo ''+modsz+'') when values aren't passed.
How to make if block execute its logic when no values are passed?
Your code always jumps to the "else" block, because
"".split(',')
produces an array with a single empty string.
assert "".split(',').size() == 1
assert "".splti(',') == [""] as String[]
When you use active choice parameter with multiple values selection and you don't select anything, your variable name stores an empty string. You should check first if the modName parameter is not an empty string and only otherwise split and display values.
node(){
selectModName()
}
def selectModName(){
stage 'Multi selection'
if (modName) {
String[] mods = modName?.split(',')
for (mod in mods) {
echo " ${mod} is name of the module"
}
} else {
echo 'There is nothing to be printed'
}
}

Jenkinsfile Compare variable

I have a Jenkinsfile where I would like to compare two variables in expression. Say my target should have v1 and v2 the identical value, the step should be skipped, but both variables don't have the identical value, jenkins should cancel the job.
My stage for it looks like this at the moment. Unfortunately, jenkins overrides this step even if both variable ones have different values.
stage('Compare') {
when {
expression { myVar = myVar2}
}
steps {
exit
}
}
You made a mistake in your when condition. The expression myVar = myVar2 is an assignment expression (you assign value of myVar2 to variable myVar). If you want to test if two variables are equal, you need to use == operator.
stage('Compare') {
when {
expression { myVar == myVar2 }
}
steps {
exit
}
}

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