jet.pack: package your JRuby webapp for Jetty.

There are already many tools in existence that help developers run JRuby webapps on popular servlet containers, such as trinidad, warbler, mizuno, and kirk. Jetpack is not fundamentally different from these tools: like the rest of them it uses the jruby-rack jar as a foundation. The key differences are stylistic.

Jetpack:

• Uses Jetty... in all of its out-of-the-box, XML-configuration-file glory.
• Uses bundler to "vendor" all of your gems.
• Uses the jruby-complete jar, and provides convenience wrapper scripts (bin/ruby and bin/rake) in your project.
• Does not attempt to run Jetty in a ruby-first, embedded manner.
• Does not assume JRuby is already installed in your server environment (a basic JRE will do just fine).
• Does not force your ruby webapp to load files from a jar or war.

In short, Jetpack creates a little self-contained JRuby/Jetty/vendored-gem world around your ruby project, which you only need to transport to a server and fire up using a JRE.

Jetpack's implementation mainly consists of an honest, proletarian, bash-like ruby script.

Deploys need to be performed using MRI. Here is a sample section of a project Gemfile:

platforms :mri do
  gem 'jetpack'
end

Create config/jetpack.yml in your project:

jruby: "http://jruby.org.s3.amazonaws.com/downloads/1.6.5.1/jruby-complete-1.6.5.1.jar"
jetty: "http://dist.codehaus.org/jetty/jetty-hightide-7.4.5/jetty-hightide-7.4.5.v20110725.zip"
jruby-rack: "http://repository.codehaus.org/org/jruby/rack/jruby-rack/1.0.10/jruby-rack-1.0.10.jar"
app_user: "myapp"
app_root: "/usr/local/myapp/myapp"

Some other settings you might care about:

java_options: "-Xmx2048m"
http_port: 4080
https_port: 4443
max_concurrent_connections: 20
ruby_version: 1.8
app_type: rack
keystore_type: JCEKS
keystore: /data/app/secrets/mystore.jceks
keystore_password: sekret

Run Jetpack:

bundle exec jetpack .

Of note, you'll now have:

• a bin directory, with scripts that run ruby and rake, using jruby and with the gems defined in your project.
• a vendor/jetty directory, containing everything necessary to run your app using jetty.
  • You can try your app out by cd'ing into vendor/jetty and running RAILS_ENV=development java -jar start.jar
  • vendor/jetty/jetty-init is an init script that starts your project. You should symlink /etc/init.d/[appuser]-jetty to this file, and then point monit at /etc/init.d/[appuser]-jetty