Customized response sent in case of fault condition.

When duplicate workbook or workflow is created,
html respose is sent because content type
of result is 'plain/text'.

Code has been change to send 'application/json'
content type in case of exception is araise.

Change-Id: Icef1f8c5c615e21bb9da5a3d3bef9dacd308d242
Closes-Bug: #1501172

mistral/api/controllers/v2/workflow.py

@@ -180,7 +180,7 @@ class WorkflowsController(rest.RestController, hooks.HookController):
 
         return Workflows(workflows=workflow_list).to_string()
 
-    @rest_utils.wrap_pecan_controller_exception
+    @rest_utils.wrap_wsme_controller_exception
     @wsme_pecan.wsexpose(None, wtypes.text, status_code=204)
     def delete(self, name):
         """Delete the named workflow."""
@@ -195,7 +195,7 @@ class WorkflowsController(rest.RestController, hooks.HookController):
 
             db_api.delete_workflow_definition(name)
 
-    @rest_utils.wrap_pecan_controller_exception
+    @rest_utils.wrap_wsme_controller_exception
     @wsme_pecan.wsexpose(Workflows, types.uuid, int, types.uniquelist,
                          types.list, types.uniquelist)
     def get_all(self, marker=None, limit=None, sort_keys='created_at',

mistral/utils/rest_utils.py

@@ -15,9 +15,11 @@
 #    limitations under the License.
 
 import functools
+import json
 
 import pecan
 import six
+from webob import Response
 from wsme import exc
 
 from mistral import exceptions as ex
@@ -47,8 +49,12 @@ def wrap_pecan_controller_exception(func):
         try:
             return func(*args, **kwargs)
         except ex.MistralException as excp:
-            pecan.response.translatable_error = excp
-            pecan.abort(excp.http_code, six.text_type(excp))
+            return Response(
+                status=excp.http_code,
+                content_type='application/json',
+                body=json.dumps(dict(
+                    faultstring=six.text_type(excp))))
+
     return wrapped