diff options
Diffstat (limited to 'railties/lib/rails/engine.rb')
| -rw-r--r-- | railties/lib/rails/engine.rb | 145 |
1 files changed, 79 insertions, 66 deletions
diff --git a/railties/lib/rails/engine.rb b/railties/lib/rails/engine.rb index aa4f94ef1b..5757d235d2 100644 --- a/railties/lib/rails/engine.rb +++ b/railties/lib/rails/engine.rb @@ -2,11 +2,12 @@ require 'rails/railtie' require 'rails/engine/railties' require 'active_support/core_ext/module/delegation' require 'pathname' +require 'thread' 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 +16,9 @@ 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 +69,9 @@ 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: @@ -110,8 +109,8 @@ module Rails # # == Endpoint # - # An engine can be also a rack application. It can be useful if you have a rack application that - # you would like to wrap with +Engine+ and provide some of the +Engine+'s features. + # An engine can also be a rack application. It can be useful if you have a rack application that + # you would like to wrap with +Engine+ and provide with some of the +Engine+'s features. # # To do that, use the +endpoint+ method: # @@ -206,42 +205,51 @@ 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 do 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 # @@ -296,7 +304,7 @@ module Rails # helper MyEngine::SharedEngineHelper # end # - # If you want to include all of the engine's helpers, you can use #helper method on an engine's + # If you want to include all of the engine's helpers, you can use the #helper method on an engine's # instance: # # class ApplicationController < ActionController::Base @@ -312,7 +320,7 @@ module Rails # Engines can have their own migrations. The default path for migrations is exactly the same # as in application: <tt>db/migrate</tt> # - # To use engine's migrations in application you can use rake task, which copies them to + # To use engine's migrations in application you can use the rake task below, which copies them to # application's dir: # # rake ENGINE_NAME:install:migrations @@ -328,7 +336,7 @@ module Rails # # == Loading priority # - # In order to change engine's priority you can use +config.railties_order+ in main application. + # In order to change engine's priority you can use +config.railties_order+ in the main application. # It will affect the priority of loading views, helpers, assets and all the other files # related to engine or application. # @@ -350,12 +358,7 @@ module Rails Rails::Railtie::Configuration.eager_load_namespaces << base base.called_from = begin - call_stack = if Kernel.respond_to?(:caller_locations) - caller_locations.map(&:path) - else - # Remove the line number from backtraces making sure we don't leave anything behind - caller.map { |p| p.sub(/:\d+.*/, '') } - end + call_stack = caller_locations.map { |l| l.absolute_path || l.path } File.dirname(call_stack.detect { |p| p !~ %r[railties[\w.-]*/lib/rails|rack[\w.-]*/lib/rack] }) end @@ -364,6 +367,10 @@ module Rails super end + def find_root(from) + find_root_with_flag "lib", from + end + def endpoint(endpoint = nil) @endpoint ||= nil @endpoint = endpoint if endpoint @@ -401,7 +408,7 @@ 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| @@ -423,6 +430,7 @@ module Rails @env_config = nil @helpers = nil @routes = nil + @app_build_lock = Mutex.new super end @@ -480,7 +488,7 @@ module Rails helpers = Module.new all = ActionController::Base.all_helpers_from_path(helpers_paths) ActionController::Base.modules_for_helpers(all).each do |mod| - helpers.send(:include, mod) + helpers.include(mod) end helpers end @@ -493,10 +501,13 @@ module Rails # Returns the underlying rack application for this engine. def app - @app ||= begin - config.middleware = config.middleware.merge_into(default_middleware_stack) - config.middleware.build(endpoint) - end + @app || @app_build_lock.synchronize { + @app ||= begin + stack = default_middleware_stack + config.middleware = build_middleware.merge_into(stack) + config.middleware.build(endpoint) + end + } end # Returns the endpoint for this engine. If none is registered, @@ -507,31 +518,26 @@ module Rails # Define the Rack API for this engine. def call(env) - env.merge!(env_config) - if env['SCRIPT_NAME'] - env.merge! "ROUTES_#{routes.object_id}_SCRIPT_NAME" => env['SCRIPT_NAME'].dup - end - app.call(env) + req = build_request env + app.call req.env end # Defines additional Rack env configuration that is added on each call. def env_config - @env_config ||= { - 'action_dispatch.routes' => routes - } + @env_config ||= {} end # Defines the routes for this engine. If a block is given to # routes, it is appended to the engine. def routes - @routes ||= ActionDispatch::Routing::RouteSet.new + @routes ||= ActionDispatch::Routing::RouteSet.new_with_config(config) @routes.append(&Proc.new) if block_given? @routes end # Define the configuration object for the engine. def config - @config ||= Engine::Configuration.new(find_root_with_flag("lib")) + @config ||= Engine::Configuration.new(self.class.find_root(self.class.called_from)) end # Load data from db/seeds.rb file. It can be used in to load engines' @@ -555,7 +561,7 @@ 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) @@ -567,10 +573,10 @@ module Rails end initializer :add_routing_paths do |app| - paths = self.paths["config/routes.rb"].existent + routing_paths = self.paths["config/routes.rb"].existent - if routes? || paths.any? - app.routes_reloader.paths.unshift(*paths) + if routes? || routing_paths.any? + app.routes_reloader.paths.unshift(*routing_paths) app.routes_reloader.route_sets << routes end end @@ -578,7 +584,7 @@ module Rails # I18n load paths are a special case since the ones added # later have higher priority. initializer :add_locales do - config.i18n.railties_load_path.concat(paths["config/locales"].existent) + config.i18n.railties_load_path << paths["config/locales"] end initializer :add_view_paths do @@ -595,12 +601,6 @@ module Rails end end - initializer :append_assets_path, group: :all do |app| - app.config.assets.paths.unshift(*paths["vendor/assets"].existent_directories) - app.config.assets.paths.unshift(*paths["lib/assets"].existent_directories) - app.config.assets.paths.unshift(*paths["app/assets"].existent_directories) - end - initializer :prepend_helpers_path do |app| if !isolated? || (app == self) app.config.helpers_paths.unshift(*paths["app/helpers"].existent) @@ -658,8 +658,7 @@ module Rails paths["db/migrate"].existent.any? end - def find_root_with_flag(flag, default=nil) #:nodoc: - root_path = self.class.called_from + def self.find_root_with_flag(flag, root_path, default=nil) #:nodoc: while root_path && File.directory?(root_path) && !File.exist?("#{root_path}/#{flag}") parent = File.dirname(root_path) @@ -687,5 +686,19 @@ module Rails def _all_load_paths #:nodoc: @_all_load_paths ||= (config.paths.load_paths + _all_autoload_paths).uniq end + + private + + def build_request(env) + env.merge!(env_config) + req = ActionDispatch::Request.new env + req.routes = routes + req.engine_script_name = req.script_name + req + end + + def build_middleware + config.middleware + end end end |