source: subversion/sites/stateofthemap/feedback/README @ 17445

Last change on this file since 17445 was 3608, checked in by nickb, 12 years ago

feedback for stateofthemap

File size: 7.8 KB
Line 
1== Welcome to Rails
2
3Rails is a web-application and persistence framework that includes everything
4needed to create database-backed web-applications according to the
5Model-View-Control pattern of separation. This pattern splits the view (also
6called the presentation) into "dumb" templates that are primarily responsible
7for inserting pre-built data in between HTML tags. The model contains the
8"smart" domain objects (such as Account, Product, Person, Post) that holds all
9the business logic and knows how to persist themselves to a database. The
10controller handles the incoming requests (such as Save New Account, Update
11Product, Show Post) by manipulating the model and directing data to the view.
12
13In Rails, the model is handled by what's called an object-relational mapping
14layer entitled Active Record. This layer allows you to present the data from
15database rows as objects and embellish these data objects with business logic
16methods. You can read more about Active Record in
17link:files/vendor/rails/activerecord/README.html.
18
19The controller and view are handled by the Action Pack, which handles both
20layers by its two parts: Action View and Action Controller. These two layers
21are bundled in a single package due to their heavy interdependence. This is
22unlike the relationship between the Active Record and Action Pack that is much
23more separate. Each of these packages can be used independently outside of
24Rails.  You can read more about Action Pack in
25link:files/vendor/rails/actionpack/README.html.
26
27
28== Getting started
29
301. At the command prompt, start a new rails application using the rails command
31   and your application name. Ex: rails myapp
32   (If you've downloaded rails in a complete tgz or zip, this step is already done)
332. Change directory into myapp and start the web server: <tt>script/server</tt> (run with --help for options)
343. Go to http://localhost:3000/ and get "Welcome aboard: You’re riding the Rails!"
354. Follow the guidelines to start developing your application
36
37
38== Web Servers
39
40By default, Rails will try to use Mongrel and lighttpd if they are installed, otherwise
41Rails will use the WEBrick, the webserver that ships with Ruby. When you run script/server,
42Rails will check if Mongrel exists, then lighttpd and finally fall back to WEBrick. This ensures
43that you can always get up and running quickly.
44
45Mongrel is a Ruby-based webserver with a C-component (which requires compilation) that is
46suitable for development and deployment of Rails applications. If you have Ruby Gems installed,
47getting up and running with mongrel is as easy as: <tt>gem install mongrel</tt>.
48More info at: http://mongrel.rubyforge.org
49
50If Mongrel is not installed, Rails will look for lighttpd. It's considerably faster than
51Mongrel and WEBrick and also suited for production use, but requires additional
52installation and currently only works well on OS X/Unix (Windows users are encouraged
53to start with Mongrel). We recommend version 1.4.11 and higher. You can download it from
54http://www.lighttpd.net.
55
56And finally, if neither Mongrel or lighttpd are installed, Rails will use the built-in Ruby
57web server, WEBrick. WEBrick is a small Ruby web server suitable for development, but not
58for production.
59
60But of course its also possible to run Rails on any platform that supports FCGI.
61Apache, LiteSpeed, IIS are just a few. For more information on FCGI,
62please visit: http://wiki.rubyonrails.com/rails/pages/FastCGI
63
64
65== Debugging Rails
66
67Have "tail -f" commands running on the server.log and development.log. Rails will
68automatically display debugging and runtime information to these files. Debugging
69info will also be shown in the browser on requests from 127.0.0.1.
70
71
72== Breakpoints
73
74Breakpoint support is available through the script/breakpointer client. This
75means that you can break out of execution at any point in the code, investigate
76and change the model, AND then resume execution! Example:
77
78  class WeblogController < ActionController::Base
79    def index
80      @posts = Post.find(:all)
81      breakpoint "Breaking out from the list"
82    end
83  end
84
85So the controller will accept the action, run the first line, then present you
86with a IRB prompt in the breakpointer window. Here you can do things like:
87
88Executing breakpoint "Breaking out from the list" at .../webrick_server.rb:16 in 'breakpoint'
89
90  >> @posts.inspect
91  => "[#<Post:0x14a6be8 @attributes={\"title\"=>nil, \"body\"=>nil, \"id\"=>\"1\"}>,
92       #<Post:0x14a6620 @attributes={\"title\"=>\"Rails you know!\", \"body\"=>\"Only ten..\", \"id\"=>\"2\"}>]"
93  >> @posts.first.title = "hello from a breakpoint"
94  => "hello from a breakpoint"
95
96...and even better is that you can examine how your runtime objects actually work:
97
98  >> f = @posts.first
99  => #<Post:0x13630c4 @attributes={"title"=>nil, "body"=>nil, "id"=>"1"}>
100  >> f.
101  Display all 152 possibilities? (y or n)
102
103Finally, when you're ready to resume execution, you press CTRL-D
104
105
106== Console
107
108You can interact with the domain model by starting the console through <tt>script/console</tt>.
109Here you'll have all parts of the application configured, just like it is when the
110application is running. You can inspect domain models, change values, and save to the
111database. Starting the script without arguments will launch it in the development environment.
112Passing an argument will specify a different environment, like <tt>script/console production</tt>.
113
114To reload your controllers and models after launching the console run <tt>reload!</tt>
115
116To reload your controllers and models after launching the console run <tt>reload!</tt>
117
118
119
120== Description of contents
121
122app
123  Holds all the code that's specific to this particular application.
124
125app/controllers
126  Holds controllers that should be named like weblogs_controller.rb for
127  automated URL mapping. All controllers should descend from ApplicationController
128  which itself descends from ActionController::Base.
129
130app/models
131  Holds models that should be named like post.rb.
132  Most models will descend from ActiveRecord::Base.
133
134app/views
135  Holds the template files for the view that should be named like
136  weblogs/index.rhtml for the WeblogsController#index action. All views use eRuby
137  syntax.
138
139app/views/layouts
140  Holds the template files for layouts to be used with views. This models the common
141  header/footer method of wrapping views. In your views, define a layout using the
142  <tt>layout :default</tt> and create a file named default.rhtml. Inside default.rhtml,
143  call <% yield %> to render the view using this layout.
144
145app/helpers
146  Holds view helpers that should be named like weblogs_helper.rb. These are generated
147  for you automatically when using script/generate for controllers. Helpers can be used to
148  wrap functionality for your views into methods.
149
150config
151  Configuration files for the Rails environment, the routing map, the database, and other dependencies.
152
153components
154  Self-contained mini-applications that can bundle together controllers, models, and views.
155
156db
157  Contains the database schema in schema.rb.  db/migrate contains all
158  the sequence of Migrations for your schema.
159
160doc
161  This directory is where your application documentation will be stored when generated
162  using <tt>rake doc:app</tt>
163
164lib
165  Application specific libraries. Basically, any kind of custom code that doesn't
166  belong under controllers, models, or helpers. This directory is in the load path.
167
168public
169  The directory available for the web server. Contains subdirectories for images, stylesheets,
170  and javascripts. Also contains the dispatchers and the default HTML files. This should be
171  set as the DOCUMENT_ROOT of your web server.
172
173script
174  Helper scripts for automation and generation.
175
176test
177  Unit and functional tests along with fixtures. When using the script/generate scripts, template
178  test files will be generated for you and placed in this directory.
179
180vendor
181  External libraries that the application depends on. Also includes the plugins subdirectory.
182  This directory is in the load path.
Note: See TracBrowser for help on using the repository browser.