I'm using some groovy inside a Jenkins Workflow script that includes a closure.
def newMarkup = new StreamingMarkupBuilder().bind {
mkp.yield(xml)
}.toString()
As I understand it mkp should be a variable made available inside closures when using StreamMarkupBuilder, however when I try and run this I get the error,
groovy.lang.MissingPropertyException: No such property: mkp for class: WorkflowScript
So my question is why doesn't Jenkins recognise that mkp is a property of the StreamMarkupBuilder class and not the workflow script?
Sounds like a bug in groovy-cps. Try encapsulating your logic inside a method marked with the #NonCPS annotation. If it starts working, then groovy-cps is to blame, and you can file a bug in the Jenkins JIRA in the workflow-plugin component with steps to reproduce, although I suspect even with the MissingPropertyException fixed the code would still not run due to JENKINS-26481.
Related
I am working on a shared library for Jenkins, and I want to access some utilities methods between some classes, but not all of them, thus I have established some statements:
I would like to avoid using static methods, since it does not access pipeline steps directly, and passing the pipeline instance every call would be a pain;
I would like to avoid a singleton as well, or prefixing every method call with the util class' instance;
Since it is not supposed to be shared between all classes I would like to avoid putting every method as a file on vars/ special directory, but I would like a similar behavior;
Despite extending the class would be a anti-pattern, it would be acceptable, though I would like to avoid the verbose Java syntax for declaring the class the same name as the file, once it is implicit in groovy;
This question does solve my problem partially, although there are issues with serialization, I noted that when I use checkpoint and some build is resumed from some stage, the instance loses all extra methods.
This other question would have helped me fix the serialization issue, however the author seems the have solved the root cause of his problem using a way that is not the original question titled for.
Is there a way to extends a implicit script class in groovy without using the class NameOfFile extends SomeOtherClass { put every thing inside this block } syntax? And without working with inner-class?
Or else, is there a way to declare a constructor using the script groovy syntax analogue as the previous question?
Or even, is there a way to change the serialization behavior to install the extra methods again after unserializing?
Appendix
The script syntax works more-or-less like this:
Consider the content of file src/cicd/pipeline/SomePipeline.groovy:
package cicd.pipeline
// there is no need to wrap everything inside class SomePipeline,
// since it is implicit
def method() {
// instance method, here I can access pipeline steps freely
}
def static otherMethod() {
// static method, here it is unable to access pipeline steps
// without a instance
}
#groovy.transform.Field
def field
def call() {
// if the class is used as method it will run
this.method()
SomePipeline.otherMethod() // or simply otherMethod() should work
this.field = 'foo'
println "this instance ${this.getClass().canonicalName} should be cicd.pipeline.SomePipeline"
}
// any code other than methods or variables with #Field
// annotation will be inside a implicit run method that is
// triggered likewise main method but isn't a static one
def localVar = 'foo'
println "It will not execute on constructor since it is on run: $localVar"
println "Method: ${org.codehaus.groovy.runtime.StackTraceUtils.sanitize(new Throwable()).stackTrace[0].methodName}"
println "this instance ${this.getClass().canonicalName} should be cicd.pipeline.SomePipeline"
If I was going to use the Java verbose syntax I would have to wrap almost everything inside a class SomePipeline which is implicit in groovy, this is the script syntax I want to keep.
I realised that this.getClass().superclass.canonicalName when outside Jenkins pipeline is groovy.lang.Script and when inside pipeline is org.jenkinsci.plugins.workflow.cps.CpsScript and based on this resource I was able to elaborate the following solution:
abstract class CustomScript extends org.jenkinsci.plugins.workflow.cps.CpsScript {
public CustomScript() {
// do something here, it will always execute regardless
// serialization, and before everything
}
}
#groovy.transform.BaseScript CustomScript baseScript
That is it, worked as expected! Of course you can elaborate this solution better in order to reduce repeating and avoid inner-classes, but I will leave it for your imagination.
I have a question about name lookup in Groovy. Consider the following build script:
apply([plugin: 'java'])
def dependenciesClosure = {
delegate.ext.name = "DelegateName"
println name
println delegate.toString()
project(':api')
}
dependenciesClosure();
dependencies(dependenciesClosure)
The gradle check command produces the output
webapp
project ':webapp'
DelegateName
org.gradle.api.internal.artifacts.dsl.dependencies.DefaultDependencyHandler_Decorated#397ef2
Taking that into account, nonlocal variable name lookup is performed on a delegate object first an, if the name's not found, performed on the global project object. Is that correct?
Correct, Gradle uses a delegate first resolve strategy within configuration closures. In this case, the delegate is an instance of DependencyHandler. You can see what any given block delegates to by looking at the Gradle DSL documentation.
Edit: To confirm your last point, yes, the build script itself delegates to an instance of Project.
Consider the following method invokation containing in the gradle build script:
gradle.taskGraph.whenReady{taskGraph ->
println gradle.toString()
println "Ready"
}
It prints
build 'task_graph'
Ready
I thought we work in the scope of Project object, since gradle should be a property of that Project object. But there is neither property nor even method with such name. Why can we use it in the build script?
I may be wrong but I think your confusion is that there exists a getGradle() method on the Project interface but no such public field named gradle. This is a Groovy feature. In Groovy, getter and setter methods can by referenced as properties. For example:
println project.description // same as project.getDescription()
project.description = 'My java project' // same as project.setDescription('My java project')
I'd highly suggest familiarizing yourself with Groovy by checking out their documentation. You'll see a lot of differing syntax in Gradle examples simply because there are many different ways to accomplish the same thing in Groovy.
Is it possible to load an external groovy script into the groovy post build plugin instead of pasting the script content into each job? We have approximately 200 jobs so updating them all is rather time consuming. I know that I could write a script to update the config files directly (as in this post: Add Jenkins Groovy Postbuild step to all jobs), but these jobs run 24x7 so finding a window when I can restart Jenkins or reload the config is problematic.
Thanks!
Just put the following in the "Groovy script:" field:
evaluate(new File("... groovy script file name ..."));
Also, you might want to go even further.
What if script name or path changes?
Using Template plugin you can create a single "template" job, define call to groovy script (above line) in there, and in all jobs that need it add post-build action called "Use publishers from another project" referencing this template project.
Update: This is what really solved it for me: https://issues.jenkins-ci.org/browse/JENKINS-21480
"I am able to do just that by doing the following. Enter these lines in lieu of the script in the "Groovy script" box:"
// Delegate to an external script
// The filename must match the class name
import JenkinsPostBuild
def postBuild = new JenkinsPostBuild(manager)
postBuild.run()
"Then in the "Additional groovy classpath" box enter the path to that file."
We do it in the following fashion.
We have a file c:\somepath\MyScriptLibClass.groovy (accessible for Jenkins) which contains code of a groovy class MyScriptLibClass. The class contains a number of functions designed to act like static methods (to be mixed in later).
We include this functions writing the following statement in the beginning of sytem groovy and postbuild groovy steps:
[ // include lib scripts
'MyScriptLibClass'
].each{ this.metaClass.mixin(new GroovyScriptEngine('c:\\somepath').loadScriptByName(it+'.groovy')) }
This could look a bit ugly but you need to write it only once for script. You could include more than one script and also use inheritance between library classes.
Here you see that all methods from the library class are mixed in the current script. So if your class looks like:
class MyScriptLibClass {
def setBuildName( String str ){
binding?.variables['manager'].build.displayName = str
}
}
in Groovy Postbuild you could write just:
[ // include lib scripts
'MyScriptLibClass'
].each{ this.metaClass.mixin(new GroovyScriptEngine('c:\\somepath').loadScriptByName(it+'.groovy')) }
setBuildName( 'My Greatest Build' )
and it will change your current build's name.
There are also other ways to load external groovy classes and it is not necessary to use mixing in. For instance you can take a look here Compiling and using Groovy classes from Java at runtime?
How did I solve this:
Create file $JENKINS_HOME/scripts/PostbuildActions.groovy with following content:
public class PostbuildActions {
void setBuildName(Object manager, String str ){
binding?.variables['manager'].build.displayName = str
}
}
In this case in Groovy Postbuild you could write:
File script = new File("${manager.envVars['JENKINS_HOME']}/scripts/PostbuildActions.groovy")
Object actions = new GroovyClassLoader(getClass().getClassLoader()).parseClass(script).newInstance();
actions.setBuildName(manager, 'My Greatest Build');
If you wish to have the Groovy script in your Code Repository, and loaded onto the Build / Test Slave in the workspace, then you need to be aware that Groovy Postbuild runs on the Master.
For us, the master is a Unix Server, while the Build/Test Slaves are Windows PCs on the local network. As a result, prior to using the script, we must open a channel from the master to the Slave, and use a FilePath to the file.
The following worked for us:
// Get an Instance of the Build object, and from there
// the channel from the Master to the Workspace
build = Thread.currentThread().executable
channel = build.workspace.channel;
// Open a FilePath to the script
fp = new FilePath(channel, build.workspace.toString() + "<relative path to the script in Unix notation>")
// Some have suggested that the "Not NULL" check is redundant
// I've kept it for completeness
if(fp != null)
{
// 'Evaluate' requires a string, so read the file contents to a String
script = fp.readToString();
// Execute the script
evaluate(script);
}
I've just faced with the same task and tried to use #Blaskovicz approach.
Unfortunately it does not work for me, but I find upgraded code here (Zach Auclair)
Publish here with minor changes:
postbuild task
//imports
import hudson.model.*
import groovy.lang.GroovyClassLoader;
import groovy.lang.GroovyObject;
import java.io.File;
// define git file
def postBuildFile = manager.build.getEnvVars()["WORKSPACE"] + "/Jenkins/SimpleTaskPostBuildReporter.GROOVY"
def file = new File(postBuildFile)
// load custom class from file
Class groovy = this.class.classLoader.parseClass(file);
// create custom object
GroovyObject groovyObj = (GroovyObject) groovy.newInstance(manager);
// do report
groovyObj.report();
postbuild class file in git repo (SimpleTaskPostBuildReporter.GROOVY)
class SimpleTaskPostBuildReporter {
def manager
public SimpleTaskPostBuildReporter(Object manager){
if(manager == null) {
throw new RuntimeException("Manager object can't be null")
}
this.manager = manager
}
public def report() {
// do work with manager object
}
}
I haven't tried this exactly.
You could try the Jenkins Job DSL plugin which allows you to rebuild jobs from within jenkins using a Groovy DSL and supports post build groovy steps directly from the wiki
Groovy Postbuild
Executes Groovy scripts after a build.
groovyPostBuild(String script, Behavior behavior = Behavior.DoNothing)
Arguments:
script The Groovy script to execute after the build. See the plugin's
page for details on what can be done. behavior optional. If the script
fails, allows you to set mark the build as failed, unstable, or do
nothing. The behavior argument uses an enum, which currently has three
values: DoNothing, MarkUnstable, and MarkFailed.
Examples:
This example will run a groovy script that prints hello, world and if
that fails, it won't affect the build's status:
groovyPostBuild('println "hello, world"') This example will run a
groovy script, and if that fails will mark the build as failed:
groovyPostBuild('// some groovy script', Behavior.MarkFailed) This example
will run a groovy script, and if that fails will mark the
build as unstable:
groovyPostBuild('// some groovy script', Behavior.MarkUnstable) (Since 1.19)
There is a facility to use a template job (this is the bit I haven't tried) which could be the job itself so you only need to add the post build step. If you don't use a template you need to recode the whole project.
My approach is to have a script to regenerate or create all jobs from scratch just so I don't have to apply the same upgrade multiple times. Regenerated jobs keep their build history
I was able to get the following to work (I also posted on this jira issue).
in my postbuild task
this.class.classLoader.parseClass("/home/jenkins/GitlabPostbuildReporter.groovy")
GitlabPostbuildReporter.newInstance(manager).report()
in my file on disk at /home/jenkins/GitlabPostbuildReporter.groovy
class GitlabPostbuildReporter {
def manager
public GitlabPostbuildReporter(manager){
if(manager == null) {
throw new RuntimeException("Manager object musn't be null")
}
this.manager = manager
}
public def report() {
// do work with manager object
}
}
I want to call a groovy script from the other groovy script... anybody can help me in this ASAP..
example :
Class A having some code and it should call from B
class A{
static main(args){
println "Hello.. calling A Class"
}
}
I want to create a new class like B.groovy
class B{
static main(args){
// I need code for this to call A.groovy
}
}
Putting the following at the top of your script will load the contents of a groovy file.
evaluate(new File("/path/to/script/MyScript.groovy"))
You could also add this to the groovy classpath if you need to do something like this often. Hope this helps.
additionally if you need to run other scripts from your script you could do the following...
def script = new GroovyShell();
def args = ['Hello World'];
script.run(new File("/path/to/script/MyScript.groovy"), args as String[]);
Too late for the party (any beer for me?) but here I´ll show you 2 more flavors:
1) Remember the concept of Java´s CLASSPATH? That aplies to Groovy (because Groovy is Java!):
"The CLASSPATH variable is one way to tell applications, including the JDK tools, where to look for user classes.”
In order to run the script B.groovy you have to inform the location of the A.groovy (A class):
groovy –cp c:\groovy\yourscripts c:\groovy\scripts\B.groovy
The command above is telling the runtime to look in the c:\groovy\yourscripts folder because there is where we have our classes and we need them to run the B.groovy script successfully.
2) Use the GroovyClassLoader to load your scripts at runtime and using the code!
Both ways solve your needs. Now the next question is when to use each?