hal.rb in yaks-0.5.0

- old
+ new

@@ -1,22 +1,39 @@
 # -*- coding: utf-8 -*-
 
 module Yaks
   class Format
+    # Hypertext Application Language (http://stateless.co/hal_specification.html)
+    #
+    # A lightweight JSON Hypermedia message format.
+    #
+    # Options: +:plural_links+ In HAL, a single rel can correspond to
+    # a single link, or to a list of links. Which rels are singular
+    # and which are plural is application-dependant. Yaks assumes all
+    # links are singular. If your resource might contain multiple
+    # links for the same rel, then configure that rel to be plural. In
+    # that case it will always be rendered as a collection, even when
+    # the resource only contains a single link.
+    #
+    # @example
+    #
+    #   yaks = Yaks.new do
+    #     format_options :hal, {plural_links: [:related_content]}
+    #   end
+    #
     class Hal < self
-      Format.register self, :hal, 'application/hal+json'
+      register :hal, :json, 'application/hal+json'
 
       protected
 
       # @param [Yaks::Resource] resource
       # @return [Hash]
       def serialize_resource(resource)
         # The HAL spec doesn't say explicitly how to deal missing values,
         # looking at client behavior (Hyperagent) it seems safer to return an empty
         # resource.
         #
-        # return nil if resource.is_a? NullResource
         result = resource.attributes
         result = result.merge(:_links => serialize_links(resource.links)) unless resource.links.empty?
         result = result.merge(:_embedded => serialize_embedded(resource.subresources)) unless resource.subresources.empty?
         result
       end
@@ -35,10 +52,10 @@
         hal_link.merge!(link.options)
 
         memo[link.rel] = if singular?(link.rel)
                            hal_link
                          else
-                           Array(memo[link.rel]) + [hal_link]
+                           (memo[link.rel] || []) + [hal_link]
                          end
         memo
       end
 
       # @param [String] rel