HighSierraProblems: README

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1== Welcome to Rails
2
3Rails is a web-application framework that includes everything needed to create
4database-backed web applications according to the Model-View-Control pattern.
5
6This pattern splits the view (also called the presentation) into "dumb" templates
7that are primarily responsible for inserting pre-built data in between HTML tags.
8The model contains the "smart" domain objects (such as Account, Product, Person,
9Post) that holds all the business logic and knows how to persist themselves to
10a database. The controller handles the incoming requests (such as Save New Account,
11Update Product, 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 <tt>rails</tt> command
31   and your application name. Ex: rails myapp
322. Change directory into myapp and start the web server: <tt>script/server</tt> (run with --help for options)
333. Go to http://localhost:3000/ and get "Welcome aboard: You're riding the Rails!"
344. Follow the guidelines to start developing your application
35
36
37== Web Servers
38
39By default, Rails will try to use Mongrel if it's are installed when started with script/server, otherwise Rails will use WEBrick, the webserver that ships with Ruby. But you can also use Rails
40with a variety of other web servers.
41
42Mongrel is a Ruby-based webserver with a C component (which requires compilation) that is
43suitable for development and deployment of Rails applications. If you have Ruby Gems installed,
44getting up and running with mongrel is as easy as: <tt>gem install mongrel</tt>.
45More info at: http://mongrel.rubyforge.org
46
47Say other Ruby web servers like Thin and Ebb or regular web servers like Apache or LiteSpeed or
48Lighttpd or IIS. The Ruby web servers are run through Rack and the latter can either be setup to use
49FCGI or proxy to a pack of Mongrels/Thin/Ebb servers.
50
51== Apache .htaccess example for FCGI/CGI
52
53# General Apache options
54AddHandler fastcgi-script .fcgi
55AddHandler cgi-script .cgi
56Options +FollowSymLinks +ExecCGI
57
58# If you don't want Rails to look in certain directories,
59# use the following rewrite rules so that Apache won't rewrite certain requests
60#
61# Example:
62#   RewriteCond %{REQUEST_URI} ^/notrails.*
63#   RewriteRule .* - [L]
64
65# Redirect all requests not available on the filesystem to Rails
66# By default the cgi dispatcher is used which is very slow
67#
68# For better performance replace the dispatcher with the fastcgi one
69#
70# Example:
71#   RewriteRule ^(.*)$ dispatch.fcgi [QSA,L]
72RewriteEngine On
73
74# If your Rails application is accessed via an Alias directive,
75# then you MUST also set the RewriteBase in this htaccess file.
76#
77# Example:
78#   Alias /myrailsapp /path/to/myrailsapp/public
79#   RewriteBase /myrailsapp
80
81RewriteRule ^$ index.html [QSA]
82RewriteRule ^([^.]+)$ $1.html [QSA]
83RewriteCond %{REQUEST_FILENAME} !-f
84RewriteRule ^(.*)$ dispatch.cgi [QSA,L]
85
86# In case Rails experiences terminal errors
87# Instead of displaying this message you can supply a file here which will be rendered instead
88#
89# Example:
90#   ErrorDocument 500 /500.html
91
92ErrorDocument 500 "<h2>Application error</h2>Rails application failed to start properly"
93
94
95== Debugging Rails
96
97Sometimes your application goes wrong.  Fortunately there are a lot of tools that
98will help you debug it and get it back on the rails.
99
100First area to check is the application log files.  Have "tail -f" commands running
101on the server.log and development.log. Rails will automatically display debugging
102and runtime information to these files. Debugging info will also be shown in the
103browser on requests from 127.0.0.1.
104
105You can also log your own messages directly into the log file from your code using
106the Ruby logger class from inside your controllers. Example:
107
108  class WeblogController < ActionController::Base
109    def destroy
110      @weblog = Weblog.find(params[:id])
111      @weblog.destroy
112      logger.info("#{Time.now} Destroyed Weblog ID ##{@weblog.id}!")
113    end
114  end
115
116The result will be a message in your log file along the lines of:
117
118  Mon Oct 08 14:22:29 +1000 2007 Destroyed Weblog ID #1
119
120More information on how to use the logger is at http://www.ruby-doc.org/core/
121
122Also, Ruby documentation can be found at http://www.ruby-lang.org/ including:
123
124* The Learning Ruby (Pickaxe) Book: http://www.ruby-doc.org/docs/ProgrammingRuby/
125* Learn to Program: http://pine.fm/LearnToProgram/  (a beginners guide)
126
127These two online (and free) books will bring you up to speed on the Ruby language
128and also on programming in general.
129
130
131== Debugger
132
133Debugger support is available through the debugger command when you start your Mongrel or
134Webrick server with --debugger. This means that you can break out of execution at any point
135in the code, investigate and change the model, AND then resume execution!
136You need to install ruby-debug to run the server in debugging mode. With gems, use 'gem install ruby-debug'
137Example:
138
139  class WeblogController < ActionController::Base
140    def index
141      @posts = Post.find(:all)
142      debugger
143    end
144  end
145
146So the controller will accept the action, run the first line, then present you
147with a IRB prompt in the server window. Here you can do things like:
148
149  >> @posts.inspect
150  => "[#<Post:0x14a6be8 @attributes={\"title\"=>nil, \"body\"=>nil, \"id\"=>\"1\"}>,
151       #<Post:0x14a6620 @attributes={\"title\"=>\"Rails you know!\", \"body\"=>\"Only ten..\", \"id\"=>\"2\"}>]"
152  >> @posts.first.title = "hello from a debugger"
153  => "hello from a debugger"
154
155...and even better is that you can examine how your runtime objects actually work:
156
157  >> f = @posts.first
158  => #<Post:0x13630c4 @attributes={"title"=>nil, "body"=>nil, "id"=>"1"}>
159  >> f.
160  Display all 152 possibilities? (y or n)
161
162Finally, when you're ready to resume execution, you enter "cont"
163
164
165== Console
166
167You can interact with the domain model by starting the console through <tt>script/console</tt>.
168Here you'll have all parts of the application configured, just like it is when the
169application is running. You can inspect domain models, change values, and save to the
170database. Starting the script without arguments will launch it in the development environment.
171Passing an argument will specify a different environment, like <tt>script/console production</tt>.
172
173To reload your controllers and models after launching the console run <tt>reload!</tt>
174
175== dbconsole
176
177You can go to the command line of your database directly through <tt>script/dbconsole</tt>.
178You would be connected to the database with the credentials defined in database.yml.
179Starting the script without arguments will connect you to the development database. Passing an
180argument will connect you to a different database, like <tt>script/dbconsole production</tt>.
181Currently works for mysql, postgresql and sqlite.
182
183== Description of Contents
184
185app
186  Holds all the code that's specific to this particular application.
187
188app/controllers
189  Holds controllers that should be named like weblogs_controller.rb for
190  automated URL mapping. All controllers should descend from ApplicationController
191  which itself descends from ActionController::Base.
192
193app/models
194  Holds models that should be named like post.rb.
195  Most models will descend from ActiveRecord::Base.
196
197app/views
198  Holds the template files for the view that should be named like
199  weblogs/index.html.erb for the WeblogsController#index action. All views use eRuby
200  syntax.
201
202app/views/layouts
203  Holds the template files for layouts to be used with views. This models the common
204  header/footer method of wrapping views. In your views, define a layout using the
205  <tt>layout :default</tt> and create a file named default.html.erb. Inside default.html.erb,
206  call <% yield %> to render the view using this layout.
207
208app/helpers
209  Holds view helpers that should be named like weblogs_helper.rb. These are generated
210  for you automatically when using script/generate for controllers. Helpers can be used to
211  wrap functionality for your views into methods.
212
213config
214  Configuration files for the Rails environment, the routing map, the database, and other dependencies.
215
216db
217  Contains the database schema in schema.rb.  db/migrate contains all
218  the sequence of Migrations for your schema.
219
220doc
221  This directory is where your application documentation will be stored when generated
222  using <tt>rake doc:app</tt>
223
224lib
225  Application specific libraries. Basically, any kind of custom code that doesn't
226  belong under controllers, models, or helpers. This directory is in the load path.
227
228public
229  The directory available for the web server. Contains subdirectories for images, stylesheets,
230  and javascripts. Also contains the dispatchers and the default HTML files. This should be
231  set as the DOCUMENT_ROOT of your web server.
232
233script
234  Helper scripts for automation and generation.
235
236test
237  Unit and functional tests along with fixtures. When using the script/generate scripts, template
238  test files will be generated for you and placed in this directory.
239
240vendor
241  External libraries that the application depends on. Also includes the plugins subdirectory.
242  If the app has frozen rails, those gems also go here, under vendor/rails/.
243  This directory is in the load path.