Added documentation to entities

Author: Philip Champon

lib/grape/entity.rb

@@ -93,6 +93,24 @@ def self.exposures
       @exposures
     end
 
+    # Returns a hash of documentation hashes that have been declared for this Entity or ancestors. The keys
+    # are symbolized references to methods on the containing object, the values are
+    # the options that were passed into expose.
+    def self.documentation
+      @documentation ||= exposures.inject({}) do |memo, value|
+                           unless value[1][:documentation].nil? || value[1][:documentation].empty?
+                             memo[value[0]] = value[1][:documentation] 
+                           end
+                           memo
+                         end
+
+      if superclass.respond_to? :documentation
+        @documentation = superclass.documentation.merge(@documentation)
+      end
+
+      @documentation
+    end
+
     # This allows you to declare a Proc in which exposures can be formatted with.
     # It take a block with an arity of 1 which is passed as the value of the exposed attribute.
     # 
@@ -217,6 +235,10 @@ def exposures
       self.class.exposures
     end
 
+    def documentation
+      self.class.documentation
+    end
+
     def formatters
       self.class.formatters
     end

spec/grape/entity_spec.rb

@@ -317,6 +317,23 @@ class FriendEntity < Grape::Entity
       end
     end
 
+    describe '#documentation' do
+      it 'should return an empty hash is no documentation is provided' do
+        fresh_class.expose :name
+
+        subject.documentation.should == {}
+      end
+
+      it 'should return each defined documentation hash' do
+        doc = {:type => "foo", :desc => "bar"}
+        fresh_class.expose :name, :documentation => doc
+        fresh_class.expose :email, :documentation => doc
+        fresh_class.expose :birthday
+
+        subject.documentation.should == {:name  => doc, :email => doc}
+      end
+    end
+
     describe '#key_for' do
       it 'should return the attribute if no :as is set' do
         fresh_class.expose :name