diff options
Diffstat (limited to 'railties/lib/rails/engine.rb')
| -rw-r--r-- | railties/lib/rails/engine.rb | 63 |
1 files changed, 35 insertions, 28 deletions
diff --git a/railties/lib/rails/engine.rb b/railties/lib/rails/engine.rb index 83cee28fa3..1dede32dd4 100644 --- a/railties/lib/rails/engine.rb +++ b/railties/lib/rails/engine.rb @@ -6,7 +6,7 @@ require 'pathname' module Rails # <tt>Rails::Engine</tt> allows you to wrap a specific Rails application or subset of # functionality and share it with other applications or within a larger packaged application. - # Since Rails 3.0, every <tt>Rails::Application</tt> is just an engine, which allows for simple + # Every <tt>Rails::Application</tt> is just an engine, which allows for simple # feature and application sharing. # # Any <tt>Rails::Engine</tt> is also a <tt>Rails::Railtie</tt>, so the same @@ -15,10 +15,9 @@ module Rails # # == Creating an Engine # - # In Rails versions prior to 3.0, your gems automatically behaved as engines, however, - # this coupled Rails to Rubygems. Since Rails 3.0, if you want a gem to automatically - # behave as an engine, you have to specify an +Engine+ for it somewhere inside - # your plugin's +lib+ folder (similar to how we specify a +Railtie+): + # If you want a gem to behave as an engine, you have to specify an +Engine+ + # for it somewhere inside your plugin's +lib+ folder (similar to how we + # specify a +Railtie+): # # # lib/my_engine.rb # module MyEngine @@ -69,10 +68,9 @@ module Rails # # == Paths # - # Since Rails 3.0, applications and engines have more flexible path configuration (as - # opposed to the previous hardcoded path configuration). This means that you are not - # required to place your controllers at <tt>app/controllers</tt>, but in any place - # which you find convenient. + # Applications and engines have flexible path configuration, meaning that you + # are not required to place your controllers at <tt>app/controllers</tt>, but + # in any place which you find convenient. # # For example, let's suppose you want to place your controllers in <tt>lib/controllers</tt>. # You can set that as an option: @@ -206,42 +204,51 @@ module Rails # With such an engine, everything that is inside the +MyEngine+ module will be isolated from # the application. # - # Consider such controller: + # Consider this controller: # # module MyEngine # class FooController < ActionController::Base # end # end # - # If an engine is marked as isolated, +FooController+ has access only to helpers from +Engine+ and - # <tt>url_helpers</tt> from <tt>MyEngine::Engine.routes</tt>. + # If the +MyEngine+ engine is marked as isolated, +FooController+ only has + # access to helpers from +MyEngine+, and <tt>url_helpers</tt> from + # <tt>MyEngine::Engine.routes</tt>. # - # The next thing that changes in isolated engines is the behavior of routes. Normally, when you namespace - # your controllers, you also need to namespace all your routes. With an isolated engine, - # the namespace is applied by default, so you can ignore it in routes: + # The next thing that changes in isolated engines is the behavior of routes. + # Normally, when you namespace your controllers, you also need to namespace + # the related routes. With an isolated engine, the engine's namespace is + # automatically applied, so you don't need to specify it explicity in your + # routes: # # MyEngine::Engine.routes.draw do # resources :articles # end # - # The routes above will automatically point to <tt>MyEngine::ArticlesController</tt>. Furthermore, you don't - # need to use longer url helpers like <tt>my_engine_articles_path</tt>. Instead, you should simply use - # <tt>articles_path</tt> as you would do with your application. + # If +MyEngine+ is isolated, The routes above will point to + # <tt>MyEngine::ArticlesController</tt>. You also don't need to use longer + # url helpers like +my_engine_articles_path+. Instead, you should simply use + # +articles_path+, like you would do with your main application. # - # To make that behavior consistent with other parts of the framework, an isolated engine also has influence on - # <tt>ActiveModel::Naming</tt>. When you use a namespaced model, like <tt>MyEngine::Article</tt>, it will normally - # use the prefix "my_engine". In an isolated engine, the prefix will be omitted in url helpers and - # form fields for convenience. + # To make this behavior consistent with other parts of the framework, + # isolated engines also have an effect on <tt>ActiveModel::Naming</tt>. In a + # normal Rails app, when you use a namespaced model such as + # <tt>Namespace::Article</tt>, <tt>ActiveModel::Naming</tt> will generate + # names with the prefix "namespace". In an isolated engine, the prefix will + # be omitted in url helpers and form fields, for convenience. # - # polymorphic_url(MyEngine::Article.new) # => "articles_path" + # polymorphic_url(MyEngine::Article.new) + # # => "articles_path" # not "my_engine_articles_path" # # form_for(MyEngine::Article.new) do # text_field :title # => <input type="text" name="article[title]" id="article_title" /> # end # - # Additionally, an isolated engine will set its name according to namespace, so - # MyEngine::Engine.engine_name will be "my_engine". It will also set MyEngine.table_name_prefix - # to "my_engine_", changing the MyEngine::Article model to use the my_engine_articles table. + # Additionally, an isolated engine will set its own name according to its + # namespace, so <tt>MyEngine::Engine.engine_name</tt> will return + # "my_engine". It will also set +MyEngine.table_name_prefix+ to "my_engine_", + # meaning for example that <tt>MyEngine::Article</tt> will use the + # +my_engine_articles+ database table by default. # # == Using Engine's routes outside Engine # @@ -405,7 +412,7 @@ module Rails end end - # Finds engine with given path + # Finds engine with given path. def find(path) expanded_path = File.expand_path path Rails::Engine.subclasses.each do |klass| @@ -559,7 +566,7 @@ module Rails # and the load_once paths. # # This needs to be an initializer, since it needs to run once - # per engine and get the engine as a block parameter + # per engine and get the engine as a block parameter. initializer :set_autoload_paths, before: :bootstrap_hook do ActiveSupport::Dependencies.autoload_paths.unshift(*_all_autoload_paths) ActiveSupport::Dependencies.autoload_once_paths.unshift(*_all_autoload_once_paths) |