Added authentication framework to protect actions behind a condition and redirect on failure. See ActionController::Authentication for more.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@351 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

3 files changed, 101 insertions, 2 deletions

diff --git a/actionpack/lib/action_controller/authentication.rb b/actionpack/lib/action_controller/authentication.rb
new file mode 100644
index 0000000000..3ba193c1b2
--- /dev/null
+++ b/actionpack/lib/action_controller/authentication.rb
@@ -0,0 +1,99 @@
+module ActionController #:nodoc:
+  module Authentication #:nodoc:
+    def self.append_features(base)
+      super
+      base.extend(ClassMethods)
+    end
+
+    # Authentication standardizes the need to protect certain actions unless a given condition is fulfilled. It doesn't address
+    # _how_ someone becomes authorized, but only that if the condition isn't fulfilled a redirect to a given place will happen.
+    #
+    # The authentication model is setup up in two stages. One to configure the authentication, which is often done in the super-most
+    # class (such as ApplicationController in Rails), and then the protection of actions in the individual controller subclasses:
+    #
+    #   class ApplicationController < ActionController::Base
+    #     authentication :by => '@session[:authenticated]', :failure => { :controller => "login" }
+    #   end
+    #   
+    #   class WeblogController < ApplicationController
+    #     authenticates :edit, :update
+    #
+    #     def show()   render_text "I showed something"  end
+    #     def index()  render_text "I indexed something" end
+    #     def edit()   render_text "I edited something"  end
+    #     def update() render_text "I updated something" end
+    #     def login()  @session[:authenticated] = true; render_nothing end
+    #   end
+    # 
+    # In the example above, the edit and update methods are protected by an authentication condition that requires 
+    # <tt>@session[:authenticated]</tt> to be true. If that is not the case, the request is redirected to LoginController#index.
+    # Note that the :by condition is enclosed in single quotes. This is because we want to defer evaluation of the condition until
+    # we're at run time. Also note, that the :failure option uses the same format as Base#url_for and friends do to perform the redirect.
+    module ClassMethods
+      # Enables authentication for this class and all its subclasses.
+      #
+      # Options are:
+      # * <tt>:by</tt> - the code fragment that will be evaluated on each request to determine whether the request is authenticated.
+      # * <tt>:failure</tt> - redirection options following the format of Base#url_for.
+      def authentication(options)
+        options.assert_valid_keys([:by, :failure])
+        class_eval <<-EOV
+          protected          
+            def actions_excepted_from_authentication
+              self.class.read_inheritable_attribute("actions_excepted_from_authentication") || []
+            end
+          
+            def actions_included_in_authentication
+              actions = self.class.read_inheritable_attribute("actions_included_in_authentication")
+
+              if actions == :all
+                action_methods.collect { |action| action.intern }
+              elsif actions.is_a?(Array)
+                actions
+              else
+                []
+              end
+            end
+          
+            def action_needs_authentication?
+              if actions_excepted_from_authentication.include?(action_name.intern)
+                false
+              elsif actions_included_in_authentication.include?(action_name.intern)
+                true
+              elsif actions_excepted_from_authentication.length > 0
+                true
+              else
+                false
+              end
+            end
+          
+            def authenticate
+              if !action_needs_authentication? || #{options[:by]}
+                return true
+              else
+                redirect_to(#{options[:failure].inspect})
+                return false
+              end
+            end
+        EOV
+
+        before_filter :authenticate
+      end
+      
+      # Protects the actions specified behind the authentication condition.
+      def authenticates(*actions)
+        write_inheritable_array("actions_included_in_authentication", actions)
+      end
+
+      # Protects all the actions of this controller behind the authentication condition.
+      def authenticates_all
+        write_inheritable_attribute("actions_included_in_authentication", :all)
+      end
+      
+      # Protects all the actions of this controller _except_ the listed behind the authentication condition.
+      def authenticates_all_except(*actions)
+        write_inheritable_array("actions_excepted_from_authentication", actions)
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/actionpack/lib/action_controller/base.rb b/actionpack/lib/action_controller/base.rb
index 851a382682..dbdce1bbfd 100755
--- a/actionpack/lib/action_controller/base.rb
+++ b/actionpack/lib/action_controller/base.rb
@@ -602,7 +602,7 @@ module ActionController #:nodoc:
 
       def action_methods
         action_controller_classes = self.class.ancestors.reject{ |a| [Object, Kernel].include?(a) }
-        action_controller_classes.inject([]) { |action_methods, klass| action_methods + klass.instance_methods(false) }
+        action_controller_classes.inject([]) { |action_methods, klass| action_methods + klass.public_instance_methods(false) }
       end
 
       def add_variables_to_assigns
diff --git a/actionpack/lib/action_controller/filters.rb b/actionpack/lib/action_controller/filters.rb
index 1691f031f8..1ae2ea2251 100644
--- a/actionpack/lib/action_controller/filters.rb
+++ b/actionpack/lib/action_controller/filters.rb
@@ -3,7 +3,7 @@ module ActionController #:nodoc:
     def self.append_features(base)
       super
       base.extend(ClassMethods)
-      base.class_eval { include ActionController::Filters::InstanceMethods }
+      base.send(:include, ActionController::Filters::InstanceMethods)
     end
 
     # Filters enable controllers to run shared pre and post processing code for its actions. These filters can be used to do