define #content_type instead of ambiguous #content_types

Author: joeyAghion

README.markdown

@@ -215,7 +215,7 @@ By default, Grape supports _XML_, _JSON_, _Atom_, _RSS_, and _text_ content-type
 
 ```ruby
 class Twitter::API < Grape::API
-  content_types :xls => "application/vnd.ms-excel"
+  content_type :xls, "application/vnd.ms-excel"
 end
 ```
 

lib/grape/api.rb

@@ -123,9 +123,9 @@ def error_format(new_format = nil)
       end
 
       # Specify additional content-types, e.g.:
-      #   content_types :xls => 'application/vnd.ms-excel'
-      def content_types(map = {})
-        map.any? ? set(:content_types, map) : settings[:content_types]
+      #   content_type :xls, 'application/vnd.ms-excel'
+      def content_type(key, val)
+        settings.imbue(:content_types, key.to_sym => val)
       end
 
       # Specify the default status code for errors.

spec/grape/api_spec.rb

@@ -679,9 +679,9 @@ def hello
     end
   end
 
-  describe ".content_types" do
+  describe ".content_type" do
     it "sets additional content-type" do
-      subject.content_types :xls => "application/vnd.ms-excel"
+      subject.content_type :xls, "application/vnd.ms-excel"
       subject.get(:hello) do
         "some binary content"
       end