[rackspace|dns] error state callbacks now return an error

lib/fog/rackspace/dns.rb

@@ -5,6 +5,15 @@ module Fog
   module DNS
     class Rackspace < Fog::Service
 
+      class CallbackError < Fog::Errors::Error
+        attr_reader :response, :message, :details
+        def initialize(response)
+          @response = response
+          @message = response.body['error']['message']
+          @details = response.body['error']['details']
+        end
+      end
+
       US_ENDPOINT = 'https://dns.api.rackspacecloud.com/v1.0'
       UK_ENDPOINT = 'https://lon.dns.api.rackspacecloud.com/v1.0'
 

lib/fog/rackspace/models/dns/callback.rb

@@ -11,8 +11,10 @@ module Fog
           response = nil
           Fog.wait_for(timeout, interval) do
             response = connection.callback job_id
-            if response.body['status'] != 'RUNNING'
+            if response.body['status'] == 'COMPLETED'
               true
+            elsif response.body['status'] == 'ERROR'
+              raise Fog::DNS::Rackspace::CallbackError.new(response)
             elsif retries == 0
               raise Fog::Errors::Error.new("Wait on job #{job_id} took too long")
             else

tests/rackspace/models/dns/zone_tests.rb

@@ -0,0 +1,13 @@
+Shindo.tests('Fog::Rackspace::DNS | zone', ['rackspace']) do
+
+  provider = Fog::DNS[:rackspace]
+  domain_name = uniq_id + '.com'
+
+  zone = provider.zones.create({:domain => domain_name, :email => 'hostmaster@' + domain_name})
+
+  tests('adding same domain twice throws error').raises(Fog::DNS::Rackspace::CallbackError) do
+    provider.zones.create({:domain => domain_name, :email => 'hostmaster@' + domain_name})
+  end
+
+  zone.destroy
+end