For political reasons, I needed to ship a single jar file. I didn’t want to have the overhead of a war & an appserver, so I set out to embed my rails app within a single jar file. I needed to make some changes in order to get it to work.
This assumes Rails 2.3.5 and JRuby 1.4.0.
First, you need to create your rails app. Freeze rails and any gems required.
Next download jruby-complete. Once you’ve done so, unzip it. I’m assuming you’ve unzipped it to complete.
Note: When you repackage the jar file, DO NOT use jar. Use zip. This is very important. If you don’t, you’ll trash your jruby instance.
Copy your rails instance to complete/META-INF/jruby.home. I assume it will be complete/META-INF/jruby.home/rails.
Next create complete/META-INF/jruby.home/bin/server with the following content:
|
1 2 3 4 5 6 7 8 |
#!/usr/bin/env ruby RAILS_ROOT = File.join(File.dirname(File.dirname(__FILE__)),'rails') require File.join(RAILS_ROOT,'config/boot') require 'commands/server' |
The RAILS_ROOT needs to be set in order to have the proper paths within the jar file.
Next, edit complete/META-INF/jruby.home/rails/vendor/rails/railties/lib/initializer.rb In the set_root_path method, edit it so it looks like this:
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 |
def set_root_path! raise 'RAILS_ROOT is not set' unless defined?(::RAILS_ROOT) raise 'RAILS_ROOT is not a directory' unless File.directory?(::RAILS_ROOT) # I changed this... mkw21 20100301 @root_path = RAILS_ROOT # Pathname is incompatible with Windows, but Windows doesn't have # real symlinks so File.expand_path is safe. # if RUBY_PLATFORM =~ /(:?mswin|mingw)/ # File.expand_path(::RAILS_ROOT)# # Otherwise use Pathname#realpath which respects symlinks. # else # Pathname.new(::RAILS_ROOT).realpath.to_s # end Object.const_set(:RELATIVE_RAILS_ROOT, ::RAILS_ROOT.dup) unless defined?(::RELATIVE_RAILS_ROOT) ::RAILS_ROOT.replace @root_path end |
This is related to paths within the jar file.
Additionally, you need to change the initialize_logger method. (this might not be needed, see below). Change
|
1 2 3 |
logger = ActiveSupport::BufferedLogger.new(configuration.log_path) |
to
|
1 2 3 |
logger = ActiveSupport::BufferedLogger.new("/tmp/transfer.log") |
The idea is to change it to something definitely outside the jar. The reason I did this, and didn’t change the config in environment.rb was that the changes in environment.rb were not getting picked up. I’ve since come to the belief that this is due to an issue with the Rack LogTailer detailed at https://rails.lighthouseapp.com/projects/8994/tickets/2350-logtailer-ignores-configlog_path. So complete/META-INF/jruby.home/rails/vendor/rails/railties/lib/rails/rack/log_tailer.rb needs to be edited. Edit the EnvironmentLog assignment to match the file we’d specified. (You may be able to substitute RAILS_DEFAULT_LOGGER but I have not tested that)
|
1 2 3 |
EnvironmentLog = "/tmp/transfer.log" |
That’s pretty much it. Zip up your exploded jar from the complete directory: zip -r ../complete.zip *. Then you can run it via java -jar complete.jar -S server.
Enjoy!
7 comments
Skip to comment form ↓
Alexander Shvets
March 2, 2010 at 3:26 pm (UTC -5) Link to this comment
Try to use warbler gem
Matt Williams
March 2, 2010 at 4:10 pm (UTC -5) Link to this comment
I am familiar with warbler.
However, in this case, I didn’t want to create a war. I needed to deliver a single jar for political reasons and didn’t want the overhead of jboss or tomcat. Nor did I want to have to maintain the installation. Ergo, the exercise to create a single jar.
Ale McHale
March 3, 2010 at 9:04 am (UTC -5) Link to this comment
Hey Matt! It’s funny that I would run into this today, as I was currently working on the same thing. I have basically the same thing running that you do … except I’m not quite done yet. I need to run multiple mongrels within the same process, as well as some other task threads running next to the mongrels.
Anyhow, no need to reply. It was just cool to run into this the week I was working on the same thing :-).
Alex McHale
March 3, 2010 at 9:49 am (UTC -5) Link to this comment
Wow, I just realized I misspelled my own name on that last post. Yikes.
eyelash grower
August 20, 2010 at 6:05 am (UTC -5) Link to this comment
Thats a definitely good submit with essential Data. Many thanks for your assist.
Prasanna
October 12, 2010 at 7:34 am (UTC -5) Link to this comment
Hi, I am currently working on integrating Java application General Architecture For Text Engineering (GATE) with Rails application using Jruby architecture. When we worked on integrating Jruby with log4j, I am getting following error :
0 [main] DEBUG Main.class – Hello world gate/Gate.java:80:in ‘: java.lang.NoClassDefFoundError: org/apache/log4 j/Logger (NativeException) from gateapp/Main.java:86:inmain’ from test.rb:12
test.rb is the name of ruby program.
I tried importing all the log4j apache library, included the class file also in the test.rb file.
When I run the java program alone its running fine. But when I generate the jar file and include them in ruby file (test.rb) , I am getting error that
java.lang.NoClassDefFoundError: org/apache/log4j/Logger (NativeException) problem is occuring. How to deal with this problem ?
Can anyone help me out over this issue ?
Matt Williams
October 12, 2010 at 11:12 am (UTC -5) Link to this comment
I’d suggest taking a look at torquebox — it’s a jboss (hence log4j) with rails integration. You can find it at http://torquebox.org.
Barring that, is log4j in your classpath?