NextLogic Singapore Blog

So the first public training is over now. I've learned a couple of things. I think this was one of the most difficult trainings I've ever been through – and even though it seems better after getting some distance there was definitely a few things we could have done better. What I really learned here is that even though Ruby on Rails is easy, it may be not so easy and really helps if you have a programming experience.

In any case here are the steps we covered in the first session. The whole point was to just get a basic scaffold running. There was a time I thought it was easy. I don't anymore :-).

1. Install everything - here's one way to do it on Windows - it worked on most of the machines but not all. Things to watch out for: in few cases ruby bin dir wasn't added to the path, in others Mysql wouldn't start yet in others Apache wouldn't start. Most of it were XP machines but I guess there were differences. As pretty much all of our development is done on Linux and MacOS I just have more experience with those platforms.
2. What you will need - 2 command prompt windows, text editor, mysql (or any other database) and browser
3. Create a directory for your applications - on Windows type this:

   cd c:\
   mkdir rails
   cd rails
   

   
   
   
   and here it is for MacOS / Linux:

   cd ~
   mkdir rails
   cd rails
   

   
   
   
   
4. Generate the basic application structure:

   rails test
   

   You should see a bunch of lines getting generated:
   
   As a result you should be able to see the following directory structure generated:
   
5. Change to the generated directory and start the server to see if we're good to go:

   ruby script/server
   

   You should see something like this - confirming that the server has been started:
   
   Now open up a browser and navigate to http://localhost:3000. You should see this page coming up:
   
   To stop the server you can press Ctr+C. To start it again just press arrow up which should repeat the last command (i.e. ruby script/server).

6. From now on we will be using the another command line window. Leave the server running in the first window.

7. Set up the database connection. The database connection parameters are set up in config/database.yml file. On most platforms it should be geneated properly, but on some you may have to add the host: localhost line. At the end it should look something like this
   
   
8. Now we can create a new database. Type this in the second command prompt window:

   			mysql -u root 
   			create database test_development;
   			create database test_test;
   			\q
   		

   You should see something like this:
   
   To verify that everything is okay run rake db:migrate and you shouldn't see any error messages. If you see warning about require_gem being obsolete - it's okay.
9. Now we generate some basic model:

   ruby script/generate model product
   

   
   
   
10. Create a Migration
    I will get to the whole migration concept in some future installments - for now just open up db/migrate/001_create_products.rb and add the following lines:
    

    class CreateProducts < ActiveRecord::Migration
      def self.up
        create_table :products do |t|
          t.column :name, :string
          t.column :description, :text
          t.column :price, :numeric
          t.column :image_url, :string
        end
      end
    
      def self.down
        drop_table :products
      end
    end
    
    

11. Now the hard part - run the migration. Running the migration will make the changes in the database. You will HAVE to have your database as well as database.yml properly set-up, otherwise this won't work.

    rake db:migrate
    

    If everything went well you should see something like this:
    
    
12. Create a controller.

    ruby script/generate controller products
    

    Just like always, you should see some lines informing you about the files being generated. Here are the new files that got generated:
    
    
13. Now just add this line to the generated controller so that it looks like this:

    class ProductsController < ApplicationController
      scaffold :product
    end
    		

14. And here we are :-) Navigate the browser to http://localhost:3000/products/list and you should see this:
    
    Go ahead and click on New and add a new product:
    
    
15. Now we've got the rice (or meat and potatos if you're from that culture) - now just make it look better. We'll add a very basic layout and some basic CSS. Both of them are from the Agile Web Development with Ruby on Rails book examples. You need to create a new file under app/views/layouts/application.rhtml and add the following to it:
    
    
    Get the Style Sheet Here
    And here's the end product:
    
    

And that's all. Easy or not - if you can do this you will be able to do anything. If you were not able to follow or the whole darn thing just wouldn't work - let me know where you had troubles.