Allow custom default extention.

lib/rack/contrib/accept_format.rb

@@ -24,18 +24,17 @@ module Rack
   # MIT-License - Cyril Rohr
   #
   class AcceptFormat
-    # Constants
-    DEFAULT_EXTENSION = ".html"
 
-    def initialize(app)
+    def initialize(app, default_extention = '.html')
+      @ext = default_extention
       @app = app
     end
 
     def call(env)
       req = Rack::Request.new(env)
       unless req.path_info =~ /(.*)\.(.+)/
         accept = env['HTTP_ACCEPT'].to_s.scan(/[^;,\s]*\/[^;,\s]*/)[0].to_s
-        extension =  Rack::Mime::MIME_TYPES.invert[accept] || DEFAULT_EXTENSION
+        extension =  Rack::Mime::MIME_TYPES.invert[accept] || @ext
         req.path_info = req.path_info+"#{extension}"
       end
       @app.call(env)

test/spec_rack_accept_format.rb

@@ -22,13 +22,19 @@ def mime(ext, type)
     specify "should add the default extension if no Accept header" do
       request = Rack::MockRequest.env_for("/resource")
       body = Rack::AcceptFormat.new(app).call(request).last
-      body.should == "/resource#{Rack::AcceptFormat::DEFAULT_EXTENSION}"
+      body.should == "/resource.html"
+    end
+
+    specify "should use custom default extension" do
+      request = Rack::MockRequest.env_for("/resource")
+      body = Rack::AcceptFormat.new(app, '.xml').call(request).last
+      body.should == "/resource.xml"
     end
 
     specify "should add the default extension if the Accept header is not registered in the Mime::Types" do
       request = Rack::MockRequest.env_for("/resource", 'HTTP_ACCEPT' => 'application/json;q=1.0, text/html;q=0.8, */*;q=0.1')
       body = Rack::AcceptFormat.new(app).call(request).last
-      body.should == "/resource#{Rack::AcceptFormat::DEFAULT_EXTENSION}"
+      body.should == "/resource.html"
     end
 
     specify "should add the correct extension if the Accept header is registered in the Mime::Types" do