Recently I was asked to switch to using Rails for a new project at my job. At my company we have had nightmares deploying our PHP applications on multiple customers environments, therefore I was asked to use jRuby instead of Ruby so that we may deploy with the JVM. In my research I came across RVM (Ruby Version Manager), a great app for managing multiple version of Ruby and/or jRuby on a single machine. In the following tutorial I will demonstrate how to install RVM and then use it to install jRuby and create a gem set. Finally we will install Rails and launch a development server to demonstrate it working.
A few things to know
When going through this tutorial, the following information is important. Whenever you see the symbol "$" this denotes the following text is a command to type in terminal. My text editor of choice is Textmate, so in my commands you will see "mate" sometimes. Feel free to replace "mate" with "nano", "vim", or which ever your editor of choice might be. Also, I am on OS X, so if you are using another Unix OS, replace my instructions to edit ".profile" with ".bashrc" or equivalent.
Step 1 :: Install RVM (Ruby Version Manager)
$ bash < <( curl http://rvm.beginrescueend.com/releases/rvm-install-head )
$ mate ~/.profile
Insert the following function at the bottom of the .profile file and save
# This loads RVM into a shell session. [[ -s "$HOME/.rvm/scripts/rvm" ]] && . "$HOME/.rvm/scripts/rvm"
Now verify RVM is properly installed
$ type rvm | head -1
You should see the following printed in terminal
rvm is a function
Step 2 :: Install jRuby
Install jRuby with RVM
$ rvm install jruby-1.5.6 $ rvm jruby-1.5.6
Check ruby version in terminal
$ ruby -v
Step 3 :: Create and set default gem set
A gem set is a collection of gems you may have for a particular project. The gem set is associated with the current version of
Ruby being used by RVM. Gem sets are useful for having complete control over which versions of gems you use for each project.
Create a gemset
$ rvm --create use jruby-1.5.6@example
Set new gemset to the default RVM uses
$ rvm --default use jruby-1.5.6@example
Step 4 :: Install Rails
Note DO NOT RUN GEM COMMANDS AS SUDO. Sudo is different user and circumnavigates where gems are stored relative to where RVM places them.
$ gem install rails --version 3.0.3
Step 5 :: Create Rails project
Create new Rails project and switch to it
$ rails new demo $ cd demo
Step 6 :: Modify Gemfile
Edit the Gemfile
$ mate Gemfile
Replace the contents of Gemfile with the following.
source 'http://rubygems.org' gem 'rails', '3.0.3' if defined?(JRUBY_VERSION) gem 'jdbc-sqlite3', '220.127.116.11.056' gem 'activerecord-jdbc-adapter', '1.1.1' gem 'activerecord-jdbcsqlite3-adapter', '1.1.1' gem 'jruby-openssl', '0.7.3' else gem 'sqlite3-ruby', :require => 'sqlite3' end
Step 7 :: Install gems with bundle
Install all of the gems in your Gemfile
$ bundle install
Step 8 :: Startup WEBrick and checkout your app!
Start a rails development server
$ rails server
Load a browser and navigate to http://localhost:3000 to checkout your dummy app.