root/agitator/README

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db setup

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1 agitator - stir the pot of your delicious links and surface interesting things
2
3 set up database:
4
5   % mysql -uroot mysql
6   mysql% GRANT ALL PRIVILEGES ON *.* TO 'jm3_spoon'@'localhost' IDENTIFIED BY 'stirthatshit' WITH GRANT OPTION;
7   mysql% create database jm3_agitator;
8
9 == Welcome to Rails
10
11 Rails is a web-application and persistence framework that includes everything
12 needed to create database-backed web-applications according to the
13 Model-View-Control pattern of separation. This pattern splits the view (also
14 called the presentation) into "dumb" templates that are primarily responsible
15 for inserting pre-built data in between HTML tags. The model contains the
16 "smart" domain objects (such as Account, Product, Person, Post) that holds all
17 the business logic and knows how to persist themselves to a database. The
18 controller handles the incoming requests (such as Save New Account, Update
19 Product, Show Post) by manipulating the model and directing data to the view.
20
21 In Rails, the model is handled by what's called an object-relational mapping
22 layer entitled Active Record. This layer allows you to present the data from
23 database rows as objects and embellish these data objects with business logic
24 methods. You can read more about Active Record in
25 link:files/vendor/rails/activerecord/README.html.
26
27 The controller and view are handled by the Action Pack, which handles both
28 layers by its two parts: Action View and Action Controller. These two layers
29 are bundled in a single package due to their heavy interdependence. This is
30 unlike the relationship between the Active Record and Action Pack that is much
31 more separate. Each of these packages can be used independently outside of
32 Rails.  You can read more about Action Pack in
33 link:files/vendor/rails/actionpack/README.html.
34
35
36 == Getting Started
37
38 1. At the command prompt, start a new Rails application using the <tt>rails</tt> command
39    and your application name. Ex: rails myapp
40    (If you've downloaded Rails in a complete tgz or zip, this step is already done)
41 2. Change directory into myapp and start the web server: <tt>script/server</tt> (run with --help for options)
42 3. Go to http://localhost:3000/ and get "Welcome aboard: You’re riding the Rails!"
43 4. Follow the guidelines to start developing your application
44
45
46 == Web Servers
47
48 By default, Rails will try to use Mongrel and lighttpd if they are installed, otherwise
49 Rails will use WEBrick, the webserver that ships with Ruby. When you run script/server,
50 Rails will check if Mongrel exists, then lighttpd and finally fall back to WEBrick. This ensures
51 that you can always get up and running quickly.
52
53 Mongrel is a Ruby-based webserver with a C component (which requires compilation) that is
54 suitable for development and deployment of Rails applications. If you have Ruby Gems installed,
55 getting up and running with mongrel is as easy as: <tt>gem install mongrel</tt>.
56 More info at: http://mongrel.rubyforge.org
57
58 If Mongrel is not installed, Rails will look for lighttpd. It's considerably faster than
59 Mongrel and WEBrick and also suited for production use, but requires additional
60 installation and currently only works well on OS X/Unix (Windows users are encouraged
61 to start with Mongrel). We recommend version 1.4.11 and higher. You can download it from
62 http://www.lighttpd.net.
63
64 And finally, if neither Mongrel or lighttpd are installed, Rails will use the built-in Ruby
65 web server, WEBrick. WEBrick is a small Ruby web server suitable for development, but not
66 for production.
67
68 But of course its also possible to run Rails on any platform that supports FCGI.
69 Apache, LiteSpeed, IIS are just a few. For more information on FCGI,
70 please visit: http://wiki.rubyonrails.com/rails/pages/FastCGI
71
72
73 == Debugging Rails
74
75 Sometimes your application goes wrong.  Fortunately there are a lot of tools that
76 will help you debug it and get it back on the rails.
77
78 First area to check is the application log files.  Have "tail -f" commands running
79 on the server.log and development.log. Rails will automatically display debugging
80 and runtime information to these files. Debugging info will also be shown in the
81 browser on requests from 127.0.0.1.
82
83 You can also log your own messages directly into the log file from your code using
84 the Ruby logger class from inside your controllers. Example:
85
86   class WeblogController < ActionController::Base
87     def destroy
88       @weblog = Weblog.find(params[:id])
89       @weblog.destroy
90       logger.info("#{Time.now} Destroyed Weblog ID ##{@weblog.id}!")
91     end
92   end
93
94 The result will be a message in your log file along the lines of:
95
96   Mon Oct 08 14:22:29 +1000 2007 Destroyed Weblog ID #1
97
98 More information on how to use the logger is at http://www.ruby-doc.org/core/
99
100 Also, Ruby documentation can be found at http://www.ruby-lang.org/ including:
101
102 * The Learning Ruby (Pickaxe) Book: http://www.ruby-doc.org/docs/ProgrammingRuby/
103 * Learn to Program: http://pine.fm/LearnToProgram/  (a beginners guide)
104
105 These two online (and free) books will bring you up to speed on the Ruby language
106 and also on programming in general.
107
108
109 == Debugger
110
111 Debugger support is available through the debugger command when you start your Mongrel or
112 Webrick server with --debugger. This means that you can break out of execution at any point
113 in the code, investigate and change the model, AND then resume execution! Example:
114
115   class WeblogController < ActionController::Base
116     def index
117       @posts = Post.find(:all)
118       debugger
119     end
120   end
121
122 So the controller will accept the action, run the first line, then present you
123 with a IRB prompt in the server window. Here you can do things like:
124
125   >> @posts.inspect
126   => "[#<Post:0x14a6be8 @attributes={\"title\"=>nil, \"body\"=>nil, \"id\"=>\"1\"}>,
127        #<Post:0x14a6620 @attributes={\"title\"=>\"Rails you know!\", \"body\"=>\"Only ten..\", \"id\"=>\"2\"}>]"
128   >> @posts.first.title = "hello from a debugger"
129   => "hello from a debugger"
130
131 ...and even better is that you can examine how your runtime objects actually work:
132
133   >> f = @posts.first
134   => #<Post:0x13630c4 @attributes={"title"=>nil, "body"=>nil, "id"=>"1"}>
135   >> f.
136   Display all 152 possibilities? (y or n)
137
138 Finally, when you're ready to resume execution, you enter "cont"
139
140
141 == Console
142
143 You can interact with the domain model by starting the console through <tt>script/console</tt>.
144 Here you'll have all parts of the application configured, just like it is when the
145 application is running. You can inspect domain models, change values, and save to the
146 database. Starting the script without arguments will launch it in the development environment.
147 Passing an argument will specify a different environment, like <tt>script/console production</tt>.
148
149 To reload your controllers and models after launching the console run <tt>reload!</tt>
150
151
152 == Description of Contents
153
154 app
155   Holds all the code that's specific to this particular application.
156
157 app/controllers
158   Holds controllers that should be named like weblogs_controller.rb for
159   automated URL mapping. All controllers should descend from ApplicationController
160   which itself descends from ActionController::Base.
161
162 app/models
163   Holds models that should be named like post.rb.
164   Most models will descend from ActiveRecord::Base.
165
166 app/views
167   Holds the template files for the view that should be named like
168   weblogs/index.erb for the WeblogsController#index action. All views use eRuby
169   syntax.
170
171 app/views/layouts
172   Holds the template files for layouts to be used with views. This models the common
173   header/footer method of wrapping views. In your views, define a layout using the
174   <tt>layout :default</tt> and create a file named default.erb. Inside default.erb,
175   call <% yield %> to render the view using this layout.
176
177 app/helpers
178   Holds view helpers that should be named like weblogs_helper.rb. These are generated
179   for you automatically when using script/generate for controllers. Helpers can be used to
180   wrap functionality for your views into methods.
181
182 config
183   Configuration files for the Rails environment, the routing map, the database, and other dependencies.
184
185 db
186   Contains the database schema in schema.rb.  db/migrate contains all
187   the sequence of Migrations for your schema.
188
189 doc
190   This directory is where your application documentation will be stored when generated
191   using <tt>rake doc:app</tt>
192
193 lib
194   Application specific libraries. Basically, any kind of custom code that doesn't
195   belong under controllers, models, or helpers. This directory is in the load path.
196
197 public
198   The directory available for the web server. Contains subdirectories for images, stylesheets,
199   and javascripts. Also contains the dispatchers and the default HTML files. This should be
200   set as the DOCUMENT_ROOT of your web server.
201
202 script
203   Helper scripts for automation and generation.
204
205 test
206   Unit and functional tests along with fixtures. When using the script/generate scripts, template
207   test files will be generated for you and placed in this directory.
208
209 vendor
210   External libraries that the application depends on. Also includes the plugins subdirectory.
211   This directory is in the load path.
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