Run groovy script from within gradle

Question

What's the best way to create a gradle task, which runs a groovy script? I realize that gradle build files are groovy, so I would think it would be possible to do something like this:

task run << {
    Script app = new GroovyShell().parse(new File("examples/foo.groovy"))
    // or replace .parse() w/ a .evalulate()?
    app.run()
}

I get all kinds of whacky errors when I try this if bar.groovy is using @Grab annotations or even doing simple imports. I want to create a gradle task to handle this, so that I can hopefully reuse the classpath definition.

Would it be better to move the examples directory into the src directory somewhere? What's a best practice?

Answer 1

Or you could do:

new GroovyShell().run(file('somePath'))

Answer 2

You could try using GroovyScriptEngine instead of the GroovyShell. I've used it previously with @Grab annotations. You will need all of groovy on the classpath, the groovy-all.jar will not be enough. I'm guessing Ivy isn't packaged in the groovy-all.jar. Something like this should to the trick:

This script presumes a groovy script at /tmp/HelloWorld.groovy

def pathToFolderOfScript = '/tmp'
def gse = new GroovyScriptEngine([pathToFolderOfScript] as String[])
gse.run('HelloWorld.groovy', new Binding())

Answer 3

http://wayback.archive.org/web/20131006153845/http://docs.codehaus.org/display/GRADLE/Cookbook#Cookbook-runningthingsfromGradle

ant.java(classname: 'com.my.classname', fork: true,
         classpath: "${sourceSets.main.runtimeClasspath.asPath}")

Answer 4

I think you probably need to run the script as a new process... e.g.,

["groovy","examples/foo.groovy"].execute()

I would guess that the way Gradle is executed is not via invoking groovy, so the setup that makes @Grab work never happens. It could also be the the version of Groovy that Gradle uses doesn't support @Grab.