Groovy Postbuild do not execute scripts on Jenkins - groovy

Question

I've written simple groovy script, but I don't know how to execute it on Jenkins.
Look at this simple script:
String jbN = System.getenv('JOB_NAME')
println jbN
println "Hello"
I would except that I will reveived at least "Hello". Script give no return. I've just received Build step 'Groovy Postbuild' marked build as failure(or success)
It seems that script is not executed.
EDIT:
I didn't add it, but I have already script which will analize logs, so I need it to execute it post-build.
The problem is bigger then I thought. Plugins: "Scriptler" or "Groovy Plugin" do not print anything.
Script which I'm trying to print out:
String jbN = System.getenv('JOB_NAME')
println jbN

Answer 1

I found the solution:
Script was executed but wasn't printed to console output.
To print result to console output you need to write:
manager.listener.logger.println("Some string") instead of println.
To make it shorter do:
logger = manager.listener.logger.&println
// and call like this:
logger("test log message")
EDIT: add in logger example and to describe how to get env vars (and how to not get them) and to hopefully save people some debugging time . . . this is simple but awkward stuff.
To get the workspace you can go through the manager object. Like this:
manager.build.workspace
To get env vars, this does not work:
String jbN = System.getenv('JOB_NAME')
It shows jbN is null.
That makes sense as JOB_NAME is not an actual system environment var.
This also does not work to get env vars, an exception is thrown:
${manager.envVars['WORKSPACE']}
This does work to get jenkins job "env vars" like WORKSPACE, JOB_NAME, BUILD_NAME:
def build = Thread.currentThread().executable
workspace = build.getEnvVars()["WORKSPACE"]
Example of use, you can call a groovy script in workspace like this:
evaluate(new File(manager.build.workspace.toString() + "/dirinworkspace/scriptname.groovy"))

Answer 2

In your case you want to use the Groovy plugin rather than the Groovy Postbuild plugin.
The Groovy Postbuild plugin is made to change the build result (postbuild).
The Groovy plugin is made to run simple Groovy scripts inside your job.

Answer 3

Click Manage Jenkins-->Script Console