This TOTD (Tip Of The Day) shows how to install Rails 2.0.x in JRuby
1.0.3 and JRuby 1.1 RC1. Then it describes how a simple Rails
application can be created and deployed using WEBrick.



First, lets deal with installing Rails 2.0.x in JRuby 1.0.3 and JRuby
1.1 RC1.



Step 1: How to install Rails
2.0.x in JRuby 1.0.3 ?

• Download and Unzip JRuby
  1.0.3. This creates "jruby-1.0.3"
  directory.
• Install Rails by giving the following command in the newly
  created directory:
  
  
  
  
  bin/jruby -S gem install rails --include-dependencies
--no-ri --no-rdoc<br>
Bulk updating Gem source index for: http://gems.rubyforge.org<br>
Successfully installed rails-2.0.2<br>
Successfully installed activesupport-2.0.2<br>
Successfully installed activerecord-2.0.2<br>
Successfully installed actionpack-2.0.2<br>
Successfully installed actionmailer-2.0.2<br>
Successfully installed activeresource-2.0.2

Step 2: How to install Rails 2.0.x
in JRuby 1.1RC1?

• Download and Unzip JRuby
  1.1 RC1. This creates "jruby-1.1RC1"
  directory.
• Install Rails by giving the following command in the newly
  created directory:
  
  
  
  
  bin/jruby -S gem install rails --no-ri --no-rdoc<br>
Updating metadata for 632 gems from http://gems.rubyforge.org<br>
............................................. installed activesupport-2.0.2<br>
Successfully installed activerecord-2.0.2<br>
Successfully installed actionpack-2.0.2<br>
Successfully installed actionmailer-2.0.2<br>
Successfully installed activeresource-2.0.2<br>
Successfully installed rails-2.0.2<br>
6 gems installed

Step 3: How to create and deploy a trivial Rails app ?

Once Rails is installed in JRuby 1.x, then the steps to develop and
deploy a simple application are exactly same and given below:

1. Create the application
1. Create a Rails template app by giving the following
   command:
   
   
   
   jruby -S rails --database mysql hello
2. Create Controller and View by giving the following
   command:
   
   
   
   
   cd hello<br>
jruby script/generate controller say hello
3. Edit Controller by giving the following command:
   
   
   
   vi app/controllers/say_controller.rb
   
   
   
   and updating the "hello" helper method to look
   like:
   
   
   
   
   def hello<br>
&nbsp; &nbsp; @hello_string = "Hello from Rail 2.0.2!!"<br>
end
4. Edit View by giving the following command:
   
   
   
   vi app/views/say/hello.html.erb
   
   
   
   and adding the following line at the end:
   
   
   
   <%= @hello_string %>
2. Rails 2.0 default is to configure a database for the
   application. Following Convention-over-Configuration, either the
   defaults can be taken in which case you need to configure the database.
   Or override the convention by specifying "
   config.frameworks
-= [ :active_record, :action_mailer ]
   " in "config/environment.rb".
   Follow the steps below if you prefer configuring the database:
1. Start MySQL server by giving the following command:
   
   
   
   
   sudo /usr/local/mysql/bin/mysqld_safe --user root<br>
Starting mysqld daemon with databases from /usr/local/mysql/data
2. Create development database by giving the following
   command:
   
   
   
   jruby -S rake db:create
3. Test the App
1. Start WEBrick, using JRuby 1.0.3, by giving the following
   command:
   
   
   
   
   jruby script/server<br>
=&gt; Booting WEBrick...<br>
=&gt; Rails application started on http://0.0.0.0:3000<br>
=&gt; Ctrl-C to shutdown server; call with --help for options<br>
[2008-02-05 23:35:02] INFO&nbsp; WEBrick 1.3.1<br>
[2008-02-05 23:35:02] INFO&nbsp; ruby 1.8.5 (2007-12-15) [java]<br>
[2008-02-05 23:35:02] INFO&nbsp; WEBrick::HTTPServer#start:
pid=13446204 port=3000<br>
     
   
   
   The application is now accessible at http://localhost:3000/say/hello.
   Accessing the application shows the following output in console:
   
   
   
   
   127.0.0.1 - - [05/Feb/2008:23:35:31 PST] "GET
/say/hello HTTP/1.1" 200 89<br>
- -&gt; /say/hello<br>
127.0.0.1 - - [05/Feb/2008:23:35:32 PST] "GET /say/hello HTTP/1.1" 200
89<br>
- -&gt; /say/hello<br>
127.0.0.1 - - [05/Feb/2008:23:35:32 PST] "GET /say/hello HTTP/1.1" 200
89<br>
- -&gt; /say/hello
   
   
2. Start WEBrick using JRuby 1.1RC1, then the following
   output is
   shown:
   
   
   
   
   =&gt; Booting WEBrick...<br>
=&gt; Rails application started on http://0.0.0.0:3000<br>
=&gt; Ctrl-C to shutdown server; call with --help for options<br>
[2008-02-05 23:37:43] INFO&nbsp; WEBrick 1.3.1<br>
[2008-02-05 23:37:43] INFO&nbsp; ruby 1.8.6 (2008-01-07) [java]<br>
[2008-02-05 23:37:43] INFO&nbsp; WEBrick::HTTPServer#start:
pid=2533 port=3000<br>
     
   
   
   Note, that even though the application was created using JRuby 1.0.3,
   it can be easily invoked using JRuby 1.1RC1 because they are using the
   same Rails version. Accessing the application in this case shows the
   following output:
   
   
   <br>
127.0.0.1 - - [05/Feb/2008:23:37:51 PST] "GET /say/hello HTTP/1.1" 200
89<br>
- -&gt; /say/hello

So, you built a simple Rails 2.0.2 application and deployed using JRuby
1.0.3 and JRuby 1.1 RC1.

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