Rails 2.0 changes the way Scaffold works. This blog walks you through the steps to create a simple CRUD application using Scaffold in Rails 2.0.

1. Download & Install JRuby 1.1 RC2.
2. Install Rails using the following command:
   
   jruby -S gem install rails
3. Create a new Rails app using the following command:
   
   cd samples; mkdir rails; cd rails
jruby -S rails books -d mysql
4. Start MySQL server in a different shell using the following command:
   
   sudo /usr/local/mysql/bin/mysqld_safe --console
5. Creat the database using the following command:
   
   cd books
jruby -S rake db:create

   This creates the database defined by RAILS_ENV (Development is default). Here are some other new database-related commands:
   
   

   db:create:all	Create all the databases (_Development, _Test, _Production)
   db:drop	Drops your database
   db:reset	Drop and Re-create your database, including migrations

6. Generate a scaffold using the following command:
   
jruby script/generate scaffold book title:string author:string isbn:string description:text
   
   The output of the command looks like:
   
      exists  app/models/
      exists  app/controllers/
      exists  app/helpers/
      create  app/views/books
      exists  app/views/layouts/
      exists  test/functional/
      exists  test/unit/
      create  app/views/books/index.html.erb
      create  app/views/books/show.html.erb
      create  app/views/books/new.html.erb
      create  app/views/books/edit.html.erb
      create  app/views/layouts/books.html.erb
      create  public/stylesheets/scaffold.css
  dependency  model
      exists    app/models/
      exists    test/unit/
      exists    test/fixtures/
      create    app/models/book.rb
      create    test/unit/book_test.rb
      create    test/fixtures/books.yml
      create    db/migrate
      create    db/migrate/001_create_books.rb
      create  app/controllers/books_controller.rb
      create  test/functional/books_controller_test.rb
      create  app/helpers/books_helper.rb
      route  map.resources :books
   
   There is no need to create the model explicitly as was the case in previous version of Rails. This creates the "db/migrate/001_create_books.rb" migration which looks like:
   
   class CreateBooks < ActiveRecord::Migration
  def self.up
    create_table :books do |t|
      t.string :title
      t.string :author
      t.string :isbn
      t.text :description

      t.timestamps
    end
  end

  def self.down
    drop_table :books
  end
end
7. Create the database tables using the following command:
   
   jruby -S rake db:migrate
8. Deploy the application on WEBrick using the following command:
   
jruby script/server
   
   The application is now available at "http://localhost:3000/books" and looks like:
   
   
   
9. Click on "New book" to see a page as shown below (with values entered):
   
   
   Click on Create button. After 2 entries have been entered, it looks like as shown below:
   
   

That's it, you've created  a simple Rails 2.0 CRUD application.

You can also deploy this application easily on GlassFish v3 gem. Just follow the instructions here and enjoy!

I'll post a follow up blog where this is much more simplifed using NetBeans 6.1 builds where JRuby 1.1 and Rails 2.0.2 are already integrated.

Technorati: totd ruby jruby rubyonrails rails2 scaffold crud netbeans glassfish v3 gem