Ruby on Rails

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This is valid for Rails 2.2.2, the version i'm using currently. May be valid for other versions.

Contents

Fast commands

  • Help yourself, use BORT for application baseline

Schema

ruby script/generate scaffold Project name:string description:text
ruby script/generate migration AddOwnerToProject
rake db:migrate
rake db:schema:dump

Routes

rake routes

Running

Debugging

  1. Install http://hoptoadapp.com/ or http://getexceptional.com/
  2. Look in log/development.log
  3. Add "debugger" somewhere in the controller
  4. Relaunch the server using "ruby script/server --debugger"
    1. now commands can be typed like "list", "up", "irb" (for an Interactive Ruby session) or "cont"
    2. Remember the name of the top level object is "self" so printing something like "p self" can be useful

script/server

Usually with:

ruby script/server

DB

rake dbconsole

Ruby

rake console

then

irb

Troubleshooting

Gems

gem install <gemname>

if it breaks, try to do:

gem install

if it still breaks, try to do:

irb
require 'rubygems'
gem 'myproblemgem', '1.0.0'

then look at the problem.

Example

for example this session shows that the "echoe" gem is not installed. When running script/server:

/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
script/server:3
Missing these required gems:
  capistrano-ext  = 1.2.1

You're running:
  ruby 1.8.7.22 at /usr/local/bin/ruby
  rubygems 1.2.0 at /usr/local/lib/ruby/gems/1.8

Run `rake gems:install` to install the missing gems.

well... indeed Captistrano-ext IS installed:

$ ls -ald /usr/local/lib/ruby/gems/1.8/gems/cap*
drwxr-xr-x   12 root  wheel  408 Jan 20 12:11 /usr/local/lib/ruby/gems/1.8/gems/capistrano-2.5.3
drwxr-xr-x    9 root  wheel  306 Jan 20 13:00 /usr/local/lib/ruby/gems/1.8/gems/capistrano-ext-1.2.1


but running the code with irb gives more details:

$ irb
>> require 'rubygems'
=> false
>> gem 'capistrano-ext', '1.2.1'
Gem::LoadError: Could not find RubyGem echoe (>= 0)

        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:578:in `report_activate_error'
        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:134:in `activate'
        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:158:in `activate'
        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:157:in `each'
        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:157:in `activate'
        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:158:in `activate'
        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:157:in `each'
        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:157:in `activate'
        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:158:in `activate'
        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:157:in `each'
        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:157:in `activate'
        from /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:49:in `gem'
        from (irb):2

So a simple:

# gem install echoe
Successfully installed echoe-3.0.2
1 gem installed
Installing ri documentation for echoe-3.0.2...
Installing RDoc documentation for echoe-3.0.2...

fixed the problem... well... you get the idea: there's a broken dependency in captistrano-ext for echoe....

Developping

CRUD

Image:Rails-cycle.png

BORT

Initialize a new BORT instance

  • Edit
./config/database.yml
./config/deploy.rb
./config/environment.rb
./config/environments/development.rb
./config/environments/production.rb
./config/environments/staging.rb
./config/environments/test.rb
./config/settings.yml
  • Type
Rake db:migrate

Modifying the Homepage

Edit file:

app/views/sessions/new.html.erb

Modifying the Database

ruby script/generate migration AddProjectTable

or directly one of these:

ruby script/generate scaffold Project name:string description:text url:string
ruby script/generate scaffold Uploadbin hashid:string orig_filename:string stored_filename:string description:text url:string has_report:boolean owner_id:integer

Deploy with Capistrano

On the server host run:

ln -s myapp.mydomain.com penguins.dreamhost.com
mkdir -p ~/myapp.mydomain.com/releases


On local host, run

cap deploy:setup
cap deploy:migrations
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