The Base Plugin

The purpose of plugin is to encapsulate useful Gradle functionality for JRuby projects. Use of this plugin replaces the need for both Bundler and Warbler in JRuby projects.

The Ruby gem dependency code for this project relies on the Rubygems Maven proxy provided by the Torquebox.

This is the base plugin. If you are interesting in doing the following then consult the pages for the appropriate plugins:

Compatilibity

This plugin requires Gradle 2.0 or better

Getting Started

buildscript {
    repositories { jcenter() }

    dependencies {
      classpath group: 'com.github.jruby-gradle', name: 'jruby-gradle-plugin', version: '0.1.2'
    }
}

apply plugin: 'com.github.jruby-gradle.base'

Adding gems

You can also add Ruby gem dependencies in your build.gradle file under the gem configuration, e.g.:

dependencies {
    gems group: 'rubygems', name: 'sinatra', version: '1.4.5'
    gems group: 'rubygems', name: 'rake', version: '10.3.+'
}

Default Tasks

The plugin provides the following tasks:

jrubyPrepareGems - Extract GEMs declared as dependencies under gems to jruby.gemInstallDir. This is as instance of JRubyPrepareGems.
jrubyPrepare - Call jrubyPrepareGems. Also copies the content of Java-based dependencies into .jarcache/ for interpreted use

JRubyExec - Task for Executing a Ruby Script

In a similar vein to JavaExec and RhinoShellExec, the JRubyExec allows for Ruby scripts to be executed in a Gradle script using JRuby.

import com.github.jrubygradle.JRubyExec

dependencies {
    jrubyExec 'rubygems:credit_card_validator:1.2.0'
}

task runMyScript( type: JRubyExec ) {
    script 'scripts/runme.rb'
    scriptArgs '-x', '-y'
}

Common methods for JRubyExec for executing a script

```script``` - ```Object``` (Usually File or String). Path to the script.
```scriptArgs``` - ```List```. List of arguments to pass to script.
```workingDir``` - ```Object``` (Usually File or String). Working directory for script.
```environment``` - ```Map```. Environment to be set. Do not set ```GEM_HOME``` or ```GEM_PATH``` with this method.
```standardInput``` - ```InputStream```. Set an input stream to be read by the script.
```standardOutput``` - ```OutputStream```. Capture the output of the script.
```errorOutput``` - ```OutputStream```. Capture the error output of the script.
```ignoreExitValue``` - ```Boolean```. Ignore the JVm exit value. Exit values are only effective if the exit value of the Ruby script is correctly communicated back to the JVM.
```configuration``` - ```String```. Configuration to copy gems from. (*)
```classpath``` - ```List```. Additional Jars/Directories to place on classpath.
```jrubyVersion``` - ```String```. JRuby version to use if not the same as ```project.jruby.execVersion```.
```gemWorkDir``` - ```File```. Provide a custom working directory for unpacking GEMs. By default each JRubyExec task uses it’s own work directory. Use this to set a common work directory for a number of tasks.

(*) If ```jRubyVersion``` has not been set, ```jrubyExec``` will used as configuration. However, if ```jRubyVersion``` has been set, no gems will be used unless an explicit configuration has been provided

Additional ```JRubyExec``` methods for controlling the JVM instance

```jvmArgs``` - ```List```. See [jvmArgs](http://www.gradle.org/docs/current/dsl/org.gradle.api.tasks.JavaExec.html#org.gradle.api.tasks.JavaExec:jvmArgs)
```allJvmArgs``` - ```List```. See [allJvmArgs](http://www.gradle.org/docs/current/dsl/org.gradle.api.tasks.JavaExec.html#org.gradle.api.tasks.JavaExec:allJvmArgs)
```systemProperties``` - ```Map```. See [systemProperties](http://www.gradle.org/docs/current/dsl/org.gradle.api.tasks.JavaExec.html#org.gradle.api.tasks.JavaExec:systemProperties)
```bootstrapClassPath``` - ```FileCollection``` or ```List```. See [bootstrapClassPath](http://www.gradle.org/docs/current/dsl/org.gradle.api.tasks.JavaExec.html#org.gradle.api.tasks.JavaExec:bootstrapClasspath)
```minHeapSize``` - ```String```. See [minHeapSize](http://www.gradle.org/docs/current/dsl/org.gradle.api.tasks.JavaExec.html)
```maxHeapSize``` - ```String```. See [maxHeapSize](http://www.gradle.org/docs/current/dsl/org.gradle.api.tasks.JavaExec.html#org.gradle.api.tasks.JavaExec:maxHeapSize)
```defaultCharacterEncoding``` - ```String```. See [defaultCharacterEncoding](http://www.gradle.org/docs/current/dsl/org.gradle.api.tasks.JavaExec.html)
```enableAssertions``` - ```Boolean```. See [enableAssertions](http://www.gradle.org/docs/current/dsl/org.gradle.api.tasks.JavaExec.html#org.gradle.api.tasks.JavaExec:enableAssertions)
```debug``` - ```Boolean```. See [debug](http://www.gradle.org/docs/current/dsl/org.gradle.api.tasks.JavaExec.html#org.gradle.api.tasks.JavaExec:debug)
```copyTo``` - ```JavaForkOptions```. See [copyTo](http://www.gradle.org/docs/current/dsl/org.gradle.api.tasks.JavaExec.html)
```executable``` - ```Object``` (Usually ```File``` or ```String```). See [executable](http://www.gradle.org/docs/current/dsl/org.gradle.api.tasks.JavaExec.html#org.gradle.api.tasks.JavaExec:executable)

jrubyexec extension

Similar to ```javaexec``` and ```exec``` it is possible to add the execution of a jruby script within another task

task needSomeRubyLove {
  jrubyexec {
    script 'scripts/runme.rb'
    scriptArgs '-x', '-y'
  }
}

The behaviour of project.jrubyexec is slightly different to that of JRubyExec.

The version of jruby-complete is strictly tied to the jruby.execVersion. Therefore trying to set jrubyVersion in the ```jrubyexec``` closure will cause a failure
GEMs and additional JARs are only taken from the jrubyExec configuration.
It is not possible to supply a configuration parameter to the jrubyexec closure.
GEMs will be installed to jruby.gemInstallDir. Existing gems will not be overwritten.

As with JRubyExec, args, setArgs and main are illegal within the jrubyexec closure. All other methods should work.

Running a Ruby PATH command

Because JRubyExec checks for the existence of the script, it might look at first whether running Ruby commands from PATH could be difficult. However, this is totally possible by utilising jrubyArgs and passing -S as one would do when using ruby or jruby on the command-line. Here is an example of running rake as task.

task rake( type : JRubyExec ) {
    jrubyArgs '-S'
    script 'rake'
    scriptArgs '/path/to/Rakefile', 'target1', 'target2'
}

or even

ext {
    rake = { String target ->
        jrubyexec {
            jrubyArgs '-S'
            script 'rake'
            scriptArgs '/path/to/Rakefile', target
        }
    }
}

JRubyPrepareGems - A task for unpacking GEMs

Unpacking occurs using the default jruby version as set by jruby.execVersion.

import com.github.jrubygradle.JRubyPrepareGems

task unpackMyGems( type : JRubyPrepareGems ) {

  // Parent directory for unpacking GEMs.
  // Gems will end up in a subdirectory 'gems/GemName-GemVersion'
  outputDir buildDir

  // Add one or more gems
  // Can be String(s), File(s), FileCollection(s) or Configuration(s)
  gems project.configuration.gems

}

Advanced Usage

Using a custom Gem repository

By default the jruby plugin will use rubygems-proxy.torquebox.org as its source of Ruby gems. This is a server operated by the Torquebox project which presents rubygems.org as a Maven repository.

If you do not wish to use this repository, you can run your own Maven proxy repository for either rubygems.org or your own gem repository by running the rubygems-servlets server.

You can then use that custom Gem repository with:

jruby {
    defaultRepositories = false
}

repositories {
    maven { url : 'http://localhost:8989/releases' }
}

dependencies {
    gems group: 'com.lookout', name: 'custom-gem', version: '1.0.+'
}

Using the Ruby interpreter

There are still plenty of cases, such as for local development, when you might not want to create a full .war file to run some tests. In order to use the same gems and .jar based dependencies, add the following to the entry point for your application:

# Hack our GEM_HOME to make sure that the `rubygems` support can find our
# unpacked gems in build/vendor/
vendored_gems = File.expand_path(File.dirname(__FILE__) + '/build/vendor')
if File.exists?(vendored_gems)
  ENV['GEM_HOME'] = vendored_gems
end

jar_cache = File.expand_path(File.dirname(__FILE__) + '/.jarcache/')
if File.exists?(jar_cache)
  # Under JRuby `require`ing a `.jar` file will result in it being added to the
  # classpath for easy importing
  Dir["#{jar_cache}/*.jar"].each { |j| require j }
end

Note: in the example above, the .rb file is assuming it’s in the top level of the source tree, i.e. where build.gradle is located

Quickstart for those unfamiliar with Gradle

Note: This assumes you already have [Gradle](http://gradle.org) installed. If you are not on Windows it is recommended that you use [GVM](http://gvmtool.net) to install Gradle

% mkdir fancy-webapp
% cd fancy-webapp
% git init
Initialized empty Git repository in /usr/home/tyler/source/github/fancy-webapp/.git/
% gradle wrapper init  # Create the wrappers to easily bootstrap others
:wrapper
:init

BUILD SUCCESSFUL

Total time: 6.411 secs
% git add gradle gradlew gradlew.bat
% git commit -m "Initial commit with gradle wrappers"

Edit the created build.gradle file in the root of fancy-webapp/ as above