Added Request#format to return the format used for the request as a mime type. If no format is specified, the first Request#accepts type is used. This means you can stop using respond_to for anything else than responses [DHH]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@5664 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

4 files changed, 32 insertions, 0 deletions

diff --git a/actionpack/CHANGELOG b/actionpack/CHANGELOG
index e2ef473fdd..072ca4a865 100644
--- a/actionpack/CHANGELOG
+++ b/actionpack/CHANGELOG
@@ -1,5 +1,11 @@
 *SVN*
 
+* Added Request#format to return the format used for the request as a mime type. If no format is specified, the first Request#accepts type is used. This means you can stop using respond_to for anything else than responses [DHH]. Examples:
+
+    GET /posts/5.xml   | request.format => Mime::XML
+    GET /posts/5.xhtml | request.format => Mime::HTML
+    GET /posts/5       | request.format => request.accepts.first (usually Mime::HTML for browsers)
+
 * Added the option for extension aliases to mime type registration [DHH]. Example (already in the default routes):
 
     Mime::Type.register "text/html", :html, %w( application/xhtml+xml ), %w( xhtml )
diff --git a/actionpack/lib/action_controller/mime_type.rb b/actionpack/lib/action_controller/mime_type.rb
index e57339b3aa..9c4fe63ab0 100644
--- a/actionpack/lib/action_controller/mime_type.rb
+++ b/actionpack/lib/action_controller/mime_type.rb
@@ -48,6 +48,10 @@ module Mime
         LOOKUP[string]
       end
 
+      def lookup_by_extension(extension)
+        EXTENSION_LOOKUP[extension]
+      end
+
       def register(string, symbol, mime_type_synonyms = [], extension_synonyms = [])
         Mime.send :const_set, symbol.to_s.upcase, Type.new(string, symbol, mime_type_synonyms)
 
diff --git a/actionpack/lib/action_controller/request.rb b/actionpack/lib/action_controller/request.rb
index 98d28d24b8..8c21adb8df 100755
--- a/actionpack/lib/action_controller/request.rb
+++ b/actionpack/lib/action_controller/request.rb
@@ -83,6 +83,16 @@ module ActionController
         end
     end
 
+    # Returns the Mime type for the format used in the request. If there is no format available, the first of the 
+    # accept types will be used. Examples:
+    #
+    #   GET /posts/5.xml   | request.format => Mime::XML
+    #   GET /posts/5.xhtml | request.format => Mime::HTML
+    #   GET /posts/5       | request.format => request.accepts.first (usually Mime::HTML for browsers)
+    def format
+      parameters[:format] ? Mime::Type.lookup_by_extension(parameters[:format]) : accepts.first
+    end
+
     # Returns true if the request's "X-Requested-With" header contains
     # "XMLHttpRequest". (The Prototype Javascript library sends this header with
     # every Ajax request.)
diff --git a/actionpack/test/controller/request_test.rb b/actionpack/test/controller/request_test.rb
index 65e88b74d8..db81eb3097 100644
--- a/actionpack/test/controller/request_test.rb
+++ b/actionpack/test/controller/request_test.rb
@@ -303,6 +303,18 @@ class RequestTest < Test::Unit::TestCase
     assert @request.head?
   end
 
+  def test_format
+    @request.instance_eval { @parameters = { :format => 'xml' } }
+    assert_equal Mime::XML, @request.format
+
+    @request.instance_eval { @parameters = { :format => 'xhtml' } }
+    assert_equal Mime::HTML, @request.format
+
+    @request.instance_eval { @parameters = { :format => nil } }
+    @request.env["HTTP_ACCEPT"] = "text/javascript"
+    assert_equal Mime::JS, @request.format
+  end
+
   protected
     def set_request_method_to(method)
       @request.env['REQUEST_METHOD'] = method.to_s.upcase