Is it possible to compile a Rails app to a Java VM JAR file?

Question

Essentially the only thing I can deploy to my deployment machine is a JAR file. I can't install JRuby, nor can I install Glassfish or Tomcat.

Is it possible to package up a Rails application (including Rails, vendored, of course) to a JAR file such that I can do

c:\my_server> java rails_app.jar

and have it run WEBRick or Mongrel within the JVM?

Answer 1

I wrote an article a year ago about how to embed your ruby sources with jruby and everything else you want into one jar file, and then run it with "java -jar myapp.jar".

It will need some work to make it boot rails I guess, but it should not be too hard. And with the complimentary jruby documentation on their wiki, i guess you can run a jetty+war thing fairly easily with this technique.

The article is here: http://blog.kesor.net/2007/08/14/jruby-in-a-jar/

Answer 2

I'd recommend that you checkout Jetty. The process for Embedding Jetty is surprisingly easy, and it should be possible to give it your servlets from your current jar file. I haven't used Ruby/Rails, though, so I'm not sure if there are any complications there.

Is it normally possible to embed all of your rails templates/models into a jar inside of a war file for deployment on Tomcat? If so, then you should be able to get embedded Jetty to pull it from your single jar as well.