Add support for errors in JSON format.

[#1956 state:committed]

Signed-off-by: Jeremy Kemper <jeremy@bitsweat.net>

2 files changed, 25 insertions, 5 deletions

diff --git a/activeresource/lib/active_resource/base.rb b/activeresource/lib/active_resource/base.rb
index 41ffb5413b..88de8b1c66 100644
--- a/activeresource/lib/active_resource/base.rb
+++ b/activeresource/lib/active_resource/base.rb
@@ -185,7 +185,7 @@ module ActiveResource
   #
   # Active Resource supports validations on resources and will return errors if any of these validations fail
   # (e.g., "First name can not be blank" and so on).  These types of errors are denoted in the response by
-  # a response code of <tt>422</tt> and an XML representation of the validation errors.  The save operation will
+  # a response code of <tt>422</tt> and an XML or JSON representation of the validation errors.  The save operation will
   # then fail (with a <tt>false</tt> return value) and the validation errors can be accessed on the resource in question.
   #
   #   ryan = Person.find(1)
@@ -194,10 +194,14 @@ module ActiveResource
   #
   #   # When
   #   # PUT http://api.people.com:3000/people/1.xml
+  #   # or
+  #   # PUT http://api.people.com:3000/people/1.json
   #   # is requested with invalid values, the response is:
   #   #
   #   # Response (422):
   #   # <errors type="array"><error>First cannot be empty</error></errors>
+  #   # or
+  #   # {"errors":["First cannot be empty"]}
   #   #
   #
   #   ryan.errors.invalid?(:first)  # => true
diff --git a/activeresource/lib/active_resource/validations.rb b/activeresource/lib/active_resource/validations.rb
index a2ba224998..4ff7be6a9e 100644
--- a/activeresource/lib/active_resource/validations.rb
+++ b/activeresource/lib/active_resource/validations.rb
@@ -7,11 +7,10 @@ module ActiveResource
   # Active Resource validation is reported to and from this object, which is used by Base#save
   # to determine whether the object in a valid state to be saved. See usage example in Validations.  
   class Errors < ActiveModel::Errors
-    # Grabs errors from the XML response.
-    def from_xml(xml)
+    # Grabs errors from an array of messages (like ActiveRecord::Validations)
+    def from_array(messages)
       clear
       humanized_attributes = @base.attributes.keys.inject({}) { |h, attr_name| h.update(attr_name.humanize => attr_name) }
-      messages = Array.wrap(Hash.from_xml(xml)['errors']['error']) rescue []
       messages.each do |message|
         attr_message = humanized_attributes.keys.detect do |attr_name|
           if message[0, attr_name.size + 1] == "#{attr_name} "
@@ -22,6 +21,18 @@ module ActiveResource
         self[:base] << message if attr_message.nil?
       end
     end
+
+    # Grabs errors from the json response.
+    def from_json(json)
+      array = ActiveSupport::JSON.decode(json)['errors'] rescue []
+      from_array array
+    end
+
+    # Grabs errors from the XML response.
+    def from_xml(xml)
+      array = Array.wrap(Hash.from_xml(xml)['errors']['error']) rescue []
+      from_array array
+    end
   end
   
   # Module to support validation and errors with Active Resource objects. The module overrides
@@ -56,7 +67,12 @@ module ActiveResource
       save_without_validation
       true
     rescue ResourceInvalid => error
-      errors.from_xml(error.response.body)
+      case error.response['Content-Type']
+      when 'application/xml'
+        errors.from_xml(error.response.body)
+      when 'application/json'
+        errors.from_json(error.response.body)
+      end
       false
     end