Suggested patch for restless

gistfile1.diff

diff --git a/restless/dj.py b/restless/dj.py
index 9af449d..d963699 100644
--- a/restless/dj.py
+++ b/restless/dj.py
@@ -6,7 +6,7 @@ from django.core.exceptions import ObjectDoesNotExist
 from django.http import HttpResponse
 from django.views.decorators.csrf import csrf_exempt

-from .exceptions import NotFound
+from .exceptions import NotFound, Unauthorized
 from .resources import Resource


@@ -36,12 +36,15 @@ class DjangoResource(Resource):
         resp.status_code = status
         return resp

-    def build_error(self, err):
-        # A bit nicer behavior surrounding things that don't exist.
+    def build_error(self, err, traceback=None):
         if isinstance(err, ObjectDoesNotExist):
+            # A bit nicer behavior surrounding things that don't exist.
             err = NotFound(msg=six.text_type(err))
-
-        return super(DjangoResource, self).build_error(err)
+        elif isinstance(err, Unauthorized):
+            pass
+        elif self.is_debug():
+            raise
+        return super(DjangoResource, self).build_error(err, traceback)

     @classmethod
     def build_url_name(cls, name, name_prefix=None):
diff --git a/restless/fl.py b/restless/fl.py
index 80dad3e..75106ca 100644
--- a/restless/fl.py
+++ b/restless/fl.py
@@ -44,6 +44,11 @@ class FlaskResource(Resource):
         from flask import current_app
         return current_app.debug

+    def build_error(self, err, traceback=None):
+        if self.is_debug():
+            raise
+        return super(FlaskResource, self).build_error(err, traceback)
+
     def build_response(self, data, status=200):
         return make_response(data, status, {
             'Content-Type': 'application/json'
diff --git a/restless/it.py b/restless/it.py
index 277c17b..ade5b5b 100644
--- a/restless/it.py
+++ b/restless/it.py
@@ -16,6 +16,11 @@ class IttyResource(Resource):
     def is_debug(self):
         return self.debug

+    def build_error(self, err, traceback=None):
+        if self.is_debug():
+            raise
+        return super(IttyResource, self).build_error(err, traceback)
+
     def build_response(self, data, status=200):
         return itty.Response(data, status=status, content_type='application/json')

diff --git a/restless/pyr.py b/restless/pyr.py
index 2d6d162..abde721 100644
--- a/restless/pyr.py
+++ b/restless/pyr.py
@@ -26,6 +26,11 @@ class PyramidResource(Resource):

         return _wrapper

+    def build_error(self, err, traceback=None):
+        if self.is_debug():
+            raise
+        return super(PyramidResource, self).build_error(err, traceback)
+
     def build_response(self, data, status=200):
         resp = Response(data, status_code=status, content_type="application/json")
         return resp
diff --git a/restless/resources.py b/restless/resources.py
index b097f6e..60d688a 100644
--- a/restless/resources.py
+++ b/restless/resources.py
@@ -1,8 +1,9 @@
 import six
+import sys

 from .constants import OK, CREATED, ACCEPTED, NO_CONTENT
 from .exceptions import MethodNotImplemented, Unauthorized
-from .utils import json, lookup_data, MoreTypesJSONEncoder
+from .utils import json, lookup_data, MoreTypesJSONEncoder, format_traceback


 class Resource(object):
@@ -181,7 +182,7 @@ class Resource(object):
         resp.status_code = status
         return resp

-    def build_error(self, err):
+    def build_error(self, err, traceback=None):
         """
         When an exception is encountered, this generates a JSON error message
         for display to the user.
@@ -190,11 +191,17 @@ class Resource(object):
             beware of sensitive data leaking.
         :type err: Exception

+        :param traceback: Traceback to be returned in debug mode.
+        :type traceback: string
+
         :returns: A response object
         """
-        data = json.dumps({
+        data = {
             'error': six.text_type(err),
-        })
+        }
+        if traceback and self.is_debug():
+            data['traceback'] = traceback
+        data = json.dumps(data)
         status = getattr(err, 'status', 500)
         return self.build_response(data, status=status)

@@ -257,10 +264,8 @@ class Resource(object):
             data = view_method(*args, **kwargs)
             serialized = self.serialize(method, endpoint, data)
         except Exception as err:
-            if self.is_debug():
-                raise
-
-            return self.build_error(err)
+            traceback = format_traceback(sys.exc_info())
+            return self.build_error(err, traceback)

         status = self.status_map.get(self.http_methods[endpoint][method], OK)
         return self.build_response(serialized, status=status)
diff --git a/restless/utils.py b/restless/utils.py
index 1e023d3..44ba0d6 100644
--- a/restless/utils.py
+++ b/restless/utils.py
@@ -1,5 +1,6 @@
 import datetime
 import decimal
+import traceback

 try:
     import json
@@ -82,3 +83,14 @@ class MoreTypesJSONEncoder(json.JSONEncoder):
             return str(data)
         else:
             return super(MoreTypesJSONEncoder, self).default(data)
+
+
+def format_traceback(exc_info):
+    stack = traceback.format_stack()
+    stack = stack[:-2]
+    stack.extend(traceback.format_tb(exc_info[2]))
+    stack.extend(traceback.format_exception_only(exc_info[0], exc_info[1]))
+    stack_str = "Traceback (most recent call last):\n"
+    stack_str += "".join(stack)
+    stack_str = stack_str[:-1]   # Remove the last \n
+    return stack_str
diff --git a/tests/test_dj.py b/tests/test_dj.py
index e59dcfd..843f341 100644
--- a/tests/test_dj.py
+++ b/tests/test_dj.py
@@ -185,8 +185,13 @@ class DjangoResourceTestCase(unittest.TestCase):
         # Special-cased above for testing.
         self.res.request = FakeHttpRequest('DELETE')

-        with self.assertRaises(Unauthorized):
-            self.res.handle('list')
+        # First with DEBUG on
+        resp = self.res.handle('list')
+        self.assertEqual(resp['Content-Type'], 'application/json')
+        self.assertEqual(resp.status_code, 401)
+        resp_json = json.loads(resp.content.decode('utf-8'))
+        self.assertEqual(resp_json['error'], 'Unauthorized.')
+        self.assertTrue('traceback' in resp_json)

         # Now with DEBUG off.
         settings.DEBUG = False