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diff --git a/railties/README b/railties/README new file mode 100644 index 0000000000..37ec8ea211 --- /dev/null +++ b/railties/README @@ -0,0 +1,243 @@ +== Welcome to Rails + +Rails is a web-application framework that includes everything needed to create +database-backed web applications according to the Model-View-Control pattern. + +This pattern splits the view (also called the presentation) into "dumb" templates +that are primarily responsible for inserting pre-built data in between HTML tags. +The model contains the "smart" domain objects (such as Account, Product, Person, +Post) that holds all the business logic and knows how to persist themselves to +a database. The controller handles the incoming requests (such as Save New Account, +Update Product, Show Post) by manipulating the model and directing data to the view. + +In Rails, the model is handled by what's called an object-relational mapping +layer entitled Active Record. This layer allows you to present the data from +database rows as objects and embellish these data objects with business logic +methods. You can read more about Active Record in +link:files/vendor/rails/activerecord/README.html. + +The controller and view are handled by the Action Pack, which handles both +layers by its two parts: Action View and Action Controller. These two layers +are bundled in a single package due to their heavy interdependence. This is +unlike the relationship between the Active Record and Action Pack that is much +more separate. Each of these packages can be used independently outside of +Rails. You can read more about Action Pack in +link:files/vendor/rails/actionpack/README.html. + + +== Getting Started + +1. At the command prompt, start a new Rails application using the <tt>rails</tt> command + and your application name. Ex: rails myapp +2. Change directory into myapp and start the web server: <tt>script/server</tt> (run with --help for options) +3. Go to http://localhost:3000/ and get "Welcome aboard: You're riding the Rails!" +4. Follow the guidelines to start developing your application + + +== Web Servers + +By 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 +with a variety of other web servers. + +Mongrel is a Ruby-based webserver with a C component (which requires compilation) that is +suitable for development and deployment of Rails applications. If you have Ruby Gems installed, +getting up and running with mongrel is as easy as: <tt>gem install mongrel</tt>. +More info at: http://mongrel.rubyforge.org + +Say other Ruby web servers like Thin and Ebb or regular web servers like Apache or LiteSpeed or +Lighttpd or IIS. The Ruby web servers are run through Rack and the latter can either be setup to use +FCGI or proxy to a pack of Mongrels/Thin/Ebb servers. + +== Apache .htaccess example for FCGI/CGI + +# General Apache options +AddHandler fastcgi-script .fcgi +AddHandler cgi-script .cgi +Options +FollowSymLinks +ExecCGI + +# If you don't want Rails to look in certain directories, +# use the following rewrite rules so that Apache won't rewrite certain requests +# +# Example: +# RewriteCond %{REQUEST_URI} ^/notrails.* +# RewriteRule .* - [L] + +# Redirect all requests not available on the filesystem to Rails +# By default the cgi dispatcher is used which is very slow +# +# For better performance replace the dispatcher with the fastcgi one +# +# Example: +# RewriteRule ^(.*)$ dispatch.fcgi [QSA,L] +RewriteEngine On + +# If your Rails application is accessed via an Alias directive, +# then you MUST also set the RewriteBase in this htaccess file. +# +# Example: +# Alias /myrailsapp /path/to/myrailsapp/public +# RewriteBase /myrailsapp + +RewriteRule ^$ index.html [QSA] +RewriteRule ^([^.]+)$ $1.html [QSA] +RewriteCond %{REQUEST_FILENAME} !-f +RewriteRule ^(.*)$ dispatch.cgi [QSA,L] + +# In case Rails experiences terminal errors +# Instead of displaying this message you can supply a file here which will be rendered instead +# +# Example: +# ErrorDocument 500 /500.html + +ErrorDocument 500 "<h2>Application error</h2>Rails application failed to start properly" + + +== Debugging Rails + +Sometimes your application goes wrong. Fortunately there are a lot of tools that +will help you debug it and get it back on the rails. + +First area to check is the application log files. Have "tail -f" commands running +on the server.log and development.log. Rails will automatically display debugging +and runtime information to these files. Debugging info will also be shown in the +browser on requests from 127.0.0.1. + +You can also log your own messages directly into the log file from your code using +the Ruby logger class from inside your controllers. Example: + + class WeblogController < ActionController::Base + def destroy + @weblog = Weblog.find(params[:id]) + @weblog.destroy + logger.info("#{Time.now} Destroyed Weblog ID ##{@weblog.id}!") + end + end + +The result will be a message in your log file along the lines of: + + Mon Oct 08 14:22:29 +1000 2007 Destroyed Weblog ID #1 + +More information on how to use the logger is at http://www.ruby-doc.org/core/ + +Also, Ruby documentation can be found at http://www.ruby-lang.org/ including: + +* The Learning Ruby (Pickaxe) Book: http://www.ruby-doc.org/docs/ProgrammingRuby/ +* Learn to Program: http://pine.fm/LearnToProgram/ (a beginners guide) + +These two online (and free) books will bring you up to speed on the Ruby language +and also on programming in general. + + +== Debugger + +Debugger support is available through the debugger command when you start your Mongrel or +Webrick server with --debugger. This means that you can break out of execution at any point +in the code, investigate and change the model, AND then resume execution! +You need to install ruby-debug to run the server in debugging mode. With gems, use 'gem install ruby-debug' +Example: + + class WeblogController < ActionController::Base + def index + @posts = Post.find(:all) + debugger + end + end + +So the controller will accept the action, run the first line, then present you +with a IRB prompt in the server window. Here you can do things like: + + >> @posts.inspect + => "[#<Post:0x14a6be8 @attributes={\"title\"=>nil, \"body\"=>nil, \"id\"=>\"1\"}>, + #<Post:0x14a6620 @attributes={\"title\"=>\"Rails you know!\", \"body\"=>\"Only ten..\", \"id\"=>\"2\"}>]" + >> @posts.first.title = "hello from a debugger" + => "hello from a debugger" + +...and even better is that you can examine how your runtime objects actually work: + + >> f = @posts.first + => #<Post:0x13630c4 @attributes={"title"=>nil, "body"=>nil, "id"=>"1"}> + >> f. + Display all 152 possibilities? (y or n) + +Finally, when you're ready to resume execution, you enter "cont" + + +== Console + +You can interact with the domain model by starting the console through <tt>script/console</tt>. +Here you'll have all parts of the application configured, just like it is when the +application is running. You can inspect domain models, change values, and save to the +database. Starting the script without arguments will launch it in the development environment. +Passing an argument will specify a different environment, like <tt>script/console production</tt>. + +To reload your controllers and models after launching the console run <tt>reload!</tt> + +== dbconsole + +You can go to the command line of your database directly through <tt>script/dbconsole</tt>. +You would be connected to the database with the credentials defined in database.yml. +Starting the script without arguments will connect you to the development database. Passing an +argument will connect you to a different database, like <tt>script/dbconsole production</tt>. +Currently works for mysql, postgresql and sqlite. + +== Description of Contents + +app + Holds all the code that's specific to this particular application. + +app/controllers + Holds controllers that should be named like weblogs_controller.rb for + automated URL mapping. All controllers should descend from ApplicationController + which itself descends from ActionController::Base. + +app/models + Holds models that should be named like post.rb. + Most models will descend from ActiveRecord::Base. + +app/views + Holds the template files for the view that should be named like + weblogs/index.html.erb for the WeblogsController#index action. All views use eRuby + syntax. + +app/views/layouts + Holds the template files for layouts to be used with views. This models the common + header/footer method of wrapping views. In your views, define a layout using the + <tt>layout :default</tt> and create a file named default.html.erb. Inside default.html.erb, + call <% yield %> to render the view using this layout. + +app/helpers + Holds view helpers that should be named like weblogs_helper.rb. These are generated + for you automatically when using script/generate for controllers. Helpers can be used to + wrap functionality for your views into methods. + +config + Configuration files for the Rails environment, the routing map, the database, and other dependencies. + +db + Contains the database schema in schema.rb. db/migrate contains all + the sequence of Migrations for your schema. + +doc + This directory is where your application documentation will be stored when generated + using <tt>rake doc:app</tt> + +lib + Application specific libraries. Basically, any kind of custom code that doesn't + belong under controllers, models, or helpers. This directory is in the load path. + +public + The directory available for the web server. Contains subdirectories for images, stylesheets, + and javascripts. Also contains the dispatchers and the default HTML files. This should be + set as the DOCUMENT_ROOT of your web server. + +script + Helper scripts for automation and generation. + +test + Unit and functional tests along with fixtures. When using the script/generate scripts, template + test files will be generated for you and placed in this directory. + +vendor + External libraries that the application depends on. Also includes the plugins subdirectory. + If the app has frozen rails, those gems also go here, under vendor/rails/. + This directory is in the load path. |