Ruby on Rails: To get started

[JPC-Masood]

To start a project in Ruby on Rails, you need to login first to your account via ssh. Once you are logged in, let's see where we are located:

[~]# pwd
/home/masood

Ok, we are in our home directory (otherwise cd ~). Let us start a project called guestbook.

[~]# rails guestbook
create
create app/controllers
create app/helpers
create app/models
create app/views/layouts
create config/environments
create components
create db
create doc
create lib
create lib/tasks
create log
create public/images
create public/javascripts
create public/stylesheets
create script/performance
create script/process
create test/fixtures
create test/functional
create test/mocks/development
create test/mocks/test
create test/unit
create vendor
create vendor/plugins
create Rakefile
create README
create app/controllers/application.rb
create app/helpers/application_helper.rb
create test/test_helper.rb
create config/database.yml
create config/routes.rb
create public/.htaccess
create config/boot.rb
create config/environment.rb
create config/environments/production.rb
create config/environments/development.rb
create config/environments/test.rb
create script/about
create script/breakpointer
create script/console
create script/destroy
create script/generate
create script/performance/benchmarker
create script/performance/profiler
create script/process/reaper
create script/process/spawner
create script/process/spinner
create script/runner
create script/server
create script/plugin
create public/dispatch.rb
create public/dispatch.cgi
create public/dispatch.fcgi
create public/404.html
create public/500.html
create public/index.html
create public/favicon.ico
create public/robots.txt
create public/images/rails.png
create public/javascripts/prototype.js
create public/javascripts/effects.js
create public/javascripts/dragdrop.js
create public/javascripts/controls.js
create doc/README_FOR_APP
create log/server.log
create log/production.log
create log/development.log
create log/test.log

Now we create a symbolic link to the public directory of our guestbook application from our web root:

[~]# cd public_html/
[~/public_html]# ln -s ../guestbook/public guestbook

Now let us see what we have on our site by visiting http://www.yourdomain.com/guestbook/

NOTE: Replace "yourdomain.com" with your account domain.You can not access it from server IP/domain or temporary URL. You need to access it using your domain name.

Most of the information on the default index.html is not for you, so you can ignore it. However, if you are an advanced Ruby on Rails programmer, you may probably tweak something on your own.

Let us now generate a controller for our guestbook application. Say MyTest.

[~]# cd ~/guestbook
[~/guestbook]# ruby script/generate controller MyTest
      exists  app/controllers/
      exists  app/helpers/
      create  app/views/my_test
      exists  test/functional/
      create  app/controllers/my_test_controller.rb
      create  test/functional/my_test_controller_test.rb
      create  app/helpers/my_test_helper.rb

Now visit http://www.yourdomain.com/guestbook/MyTest

That would bring result

Unknown action
No action responded to index

Rails tried to find a default action named index in this controller but we have not defined it yet. Let us do that:

[~/guestbook]# vi app/controllers/my_test_controller.rb

The file will have this:

class MyTestController < ApplicationController
end

and we add these bold lines in between:

class MyTestController < ApplicationController
        def index
                render_text "Hello World"
        end
end

Save and quit, and then refresh the browser. Viola! you can see the new index method. You can also access it using http://www.yourdomain.com/guestbook/MyTest/index

Let us define another method called jaguarpc

        def jaguarpc
                render_text "Jaguar Technologies provides high quality, reliable hosting solutions at prices anyone can afford."
        end

and access it using http://www.yourdomain.com/guestbook/MyTest/jaguarpc

Now we get back to our guestbook application. The above was just to get you started on rails. First we need to create a database for the guestbook. Please login to your control panel:

http://www.yourdomain.com:2082/

and create the database, its user/pass and grant privileges to the user over the db. Please note down the db name, db user and its password.

Now to tell the Rails to find this database, we edit the file:

[~/guestbook]# vi config/database.yml

In that file we need to define three db connections for three level of dbs. For now we use same connections for all three:

development:
  adapter: mysql
  database: USER_db
  host: localhost
  username: USER_dbuser
  password: ****
test:
  adapter: mysql
  database: USER_db
  host: localhost
  username: USER_dbuser
  password: ****
production:
  adapter: mysql
  database: USER_db
  host: localhost
  username: USER_dbuser
  password: ****

Rails lets you run in development mode, test mode, or production mode, using different databases. This application uses the same database for each.

Our application will hold guestbook entries, so let us create a table to hold them. Please visit phpMyAdmin from your control panel and create a table called "entries".

CREATE TABLE `entries` (
`id` INT NOT NULL AUTO_INCREMENT ,
`name` VARCHAR( 50 ) NOT NULL ,
`comments` TEXT NOT NULL ,
`date` DATE NOT NULL ,
PRIMARY KEY ( `id` ) 
) TYPE = MYISAM ;

Now we need to create an Entry model class that will hold data from the entries table in the database.

[~/guestbook]# ruby script/generate model Entry
      exists  app/models/
      exists  test/unit/
      exists  test/fixtures/
      create  app/models/entry.rb
      create  test/unit/entry_test.rb
      create  test/fixtures/entries.yml

Now if you see the model, it is an empty class:

[~/guestbook]# cat app/models/entry.rb
class Entry < ActiveRecord::Base
end

This empty class definition is the entry business object that Rails maps to the entries table (Rails is pretty smart in English language to figure that out). Let us add controller for it:

[~/guestbook]# ruby script/generate controller Entry
      exists  app/controllers/
      exists  app/helpers/
      create  app/views/entry
      exists  test/functional/
      create  app/controllers/entry_controller.rb
      create  test/functional/entry_controller_test.rb
      create  app/helpers/entry_helper.rb

Let us add some functionality to it:

[~/guestbook]# vi app/controllers/entry_controller.rb
class EntryController < ApplicationController
        scaffold :entry
end

This single line of code will bring the database table to life. It defines actions for all CRUD operations, immediately allowing us to create, read, update, and delete entries in our database! Now visit http://www.yourdomain.com/guestbook/entry and enjoy!

This small tutorial was based on "Rolling with Ruby on Rails" at onlamp.com: http://www.onlamp.com/pub/a/onlamp/2.../20/rails.html to get you started on JaguarPC hosting servers. The tutorial on onlamp is based on windows and WEBrick web server. You can ignore those and read on further on that tutorial and other tutorials:

Rolling with Ruby on Rails (Part 1)

Rolling with Ruby on Rails (Part 2)

Ajax on Rails

Also check out www.rubyonrails.com for more information.

[kalel]

Using the ln -s technique, how would I run a rails app from the root of my domain. i.e. when they go to http://mydomain.com/ they get to see a typo powered blog?

I have a feeling that simply doing ln -s on www would cause some problems for subdomains and what not.

I guess there is always a redirect with a php script or .htaccess

[JPC-Masood]

You can remove public_html and create a link from it, but obviously you would only be running that particular application from it then (no subdomains etc.).

If you want those, then you can have your application under public_html for better management. I usually do this for redirection:

create index.php in public_html

<?php
Header("Location: myapp/"); 
?>

[derekpont]

http://instiki.org/show/HomePage

Any idea if it is possible to install Instiki here at JaguarPC? I'd like to use this Ruby based wiki, but when I go to install it I get the following...

-jailshell-2.05b$ ruby instiki
/home/mysite/public_html/buswiki/instiki-ar/vendor/rails/activesupport/lib/active_support/clean_logger.rb:13:in `remove_const': constant Logger::Format not defined (NameError)
from /home/mysite/public_html/buswiki/instiki-ar/vendor/rails/activesupport/lib/active_support/clean_logger.rb:13
from /home/mysite/public_html/buswiki/instiki-ar/vendor/rails/activesupport/lib/active_support.rb:31
from ./script/../config/environment.rb:60
from ./script/server:42
from instiki:6

[JPC-Masood]

The error message is coming out of that software you are trying to install. Have you checked with the developer/vendor of instiki to find out about it?

[Weevil]

What's the best way to handle the development/production switch? From what I've seen using the environment variable is not the best way to handle it - Rails is pretty sharp, but it was clearly not designed for a shared server. Seems to me like the only choice on a shared server is to run in development mode since production mode won't reload anything without an apache restart (maybe you can force it from the console, I'm still learning). I fear it's going to require directory copying or something similarly course to keep devlopment and production separate.

[JoeWall]

hey masood, i am curious to know if you guys installed fast cgi support

weevil : it is a very bad idea to let people access the website in development mode. it takes way too much ressources. it is very slow.

[Weevil]

Wow, it's been a while since I posted that question, and admittedly I have not been able to give my Rails stuff much attention lately.

Essentially you're saying that I should plan on copying files from a development area to the production area, but I think that this became moot recently when they disallowed using symlinks in the web folders anyway.

[JPC-Masood]

hey masood, i am curious to know if you guys installed fast cgi support

yes, fastcgi support is installed.

[lobos]

hmmm everyone harps on how fast and easy rails lets you deploy stuff - well from looking at that I will just keep using php thank you very much.

[jason]

hmmm everyone harps on how fast and easy rails lets you deploy stuff - well from looking at that I will just keep using php thank you very much.

Rails lets you do certain things (like basic CRUD operations [create, retrieve, update, delete from databases]) very quickly. If you want to do more advanced things you still have to write code and using Rails means that you need to do it in Ruby, which probably means learning a new language.

I know a lot of people are passionate about ROR, but I fail to find the same feelings. I've spent the past 10 or so years becoming a PHP expert and PHP continues to be better supported than ROR on most hosts, so I see no need to switch gears at this point.

--Jason

[JPC-Masood]

For php developers: symfony open-source PHP web framework

[Thundergaming]

Ok so I have putty running and I have logged in with SSH. I type "PWD" and "home/jthunder" shows up. now if I type "Rails Guestbook" I get "Ruby: Command not found" What is wrong? Sorry I am a Uber n00b to rails...

[lamnk]

That means you haven't installed ruby or rails to create project

[Thundergaming]

Ok ROR was not installed. Now I type "Rails guestbook" and I get...

"-jailshell-3.00$ rails guestbook

Rails requires Ruby version 1.8.2 (2004-12-25) or later.
You're running 1.8.1 (2003-12-25); please upgrade to continue.

-jailshell-3.00$"

How do I upgrade?