Drop ImmediateResponse

djangorestframework/exceptions.py

+"""
+Handled exceptions raised by REST framework.
+
+In addition Django's built in 403 and 404 exceptions are handled.
+(`django.http.Http404` and `django.core.exceptions.PermissionDenied`)
+"""
 from djangorestframework import status
 
 
 class ParseError(Exception):
     status_code = status.HTTP_400_BAD_REQUEST
-    default_detail = 'Malformed request'
+    default_detail = 'Malformed request.'
 
     def __init__(self, detail=None):
         self.detail = detail or self.default_detail
@@ -11,7 +17,7 @@ class ParseError(Exception):
 
 class PermissionDenied(Exception):
     status_code = status.HTTP_403_FORBIDDEN
-    default_detail = 'You do not have permission to access this resource'
+    default_detail = 'You do not have permission to access this resource.'
 
     def __init__(self, detail=None):
         self.detail = detail or self.default_detail
@@ -19,19 +25,30 @@ class PermissionDenied(Exception):
 
 class MethodNotAllowed(Exception):
     status_code = status.HTTP_405_METHOD_NOT_ALLOWED
-    default_detail = "Method '%s' not allowed"
+    default_detail = "Method '%s' not allowed."
 
-    def __init__(self, method, detail):
+    def __init__(self, method, detail=None):
         self.detail = (detail or self.default_detail) % method
 
 
 class UnsupportedMediaType(Exception):
     status_code = status.HTTP_415_UNSUPPORTED_MEDIA_TYPE
-    default_detail = "Unsupported media type '%s' in request"
+    default_detail = "Unsupported media type '%s' in request."
 
     def __init__(self, media_type, detail=None):
         self.detail = (detail or self.default_detail) % media_type
 
-# class Throttled(Exception):
-#     def __init__(self, detail):
-#         self.detail = detail
+
+class Throttled(Exception):
+    status_code = status.HTTP_429_TOO_MANY_REQUESTS
+    default_detail = "Request was throttled. Expected available in %d seconds."
+
+    def __init__(self, wait, detail=None):
+        import math
+        self.detail = (detail or self.default_detail) % int(math.ceil(wait))
+
+
+REST_FRAMEWORK_EXCEPTIONS = (
+    ParseError, PermissionDenied, MethodNotAllowed,
+    UnsupportedMediaType, Throttled
+)

djangorestframework/permissions.py

@@ -6,9 +6,7 @@ Permission behavior is provided by mixing the :class:`mixins.PermissionsMixin` c
 """
 
 from django.core.cache import cache
-from djangorestframework import status
-from djangorestframework.exceptions import PermissionDenied
-from djangorestframework.response import ImmediateResponse
+from djangorestframework.exceptions import PermissionDenied, Throttled
 import time
 
 __all__ = (
@@ -24,11 +22,6 @@ __all__ = (
 SAFE_METHODS = ['GET', 'HEAD', 'OPTIONS']
 
 
-_503_SERVICE_UNAVAILABLE = ImmediateResponse(
-    {'detail': 'request was throttled'},
-    status=status.HTTP_503_SERVICE_UNAVAILABLE)
-
-
 class BasePermission(object):
     """
     A base class from which all permission classes should inherit.
@@ -192,7 +185,7 @@ class BaseThrottle(BasePermission):
         """
         self.history.insert(0, self.now)
         cache.set(self.key, self.history, self.duration)
-        header = 'status=SUCCESS; next=%s sec' % self.next()
+        header = 'status=SUCCESS; next=%.2f sec' % self.next()
         self.view.headers['X-Throttle'] = header
 
     def throttle_failure(self):
@@ -200,9 +193,10 @@ class BaseThrottle(BasePermission):
         Called when a request to the API has failed due to throttling.
         Raises a '503 service unavailable' response.
         """
-        header = 'status=FAILURE; next=%s sec' % self.next()
+        wait = self.next()
+        header = 'status=FAILURE; next=%.2f sec' % wait
         self.view.headers['X-Throttle'] = header
-        raise _503_SERVICE_UNAVAILABLE
+        raise Throttled(wait)
 
     def next(self):
         """
@@ -215,7 +209,7 @@ class BaseThrottle(BasePermission):
 
         available_requests = self.num_requests - len(self.history) + 1
 
-        return '%.2f' % (remaining_duration / float(available_requests))
+        return remaining_duration / float(available_requests)
 
 
 class PerUserThrottling(BaseThrottle):

djangorestframework/response.py

@@ -161,25 +161,3 @@ class Response(SimpleTemplateResponse):
             },
             status=status.HTTP_406_NOT_ACCEPTABLE,
             view=self.view, request=self.request, renderers=[renderer])
-
-
-class ImmediateResponse(Response, Exception):
-    """
-    An exception representing an Response that should be returned immediately.
-    Any content should be serialized as-is, without being filtered.
-    """
-    #TODO: this is just a temporary fix, the whole rendering/support for ImmediateResponse, should be remade : see issue #163
-
-    def render(self):
-        try:
-            return super(Response, self).render()
-        except ImmediateResponse:
-            renderer, media_type = self._determine_renderer()
-            self.renderers.remove(renderer)
-            if len(self.renderers) == 0:
-                raise RuntimeError('Caught an ImmediateResponse while '\
-                    'trying to render an ImmediateResponse')
-            return self.render()
-
-    def __init__(self, *args, **kwargs):
-        self.response = Response(*args, **kwargs)

djangorestframework/tests/response.py

@@ -4,7 +4,7 @@ import unittest
 from django.conf.urls.defaults import patterns, url, include
 from django.test import TestCase
 
-from djangorestframework.response import Response, NotAcceptable, ImmediateResponse
+from djangorestframework.response import Response, NotAcceptable
 from djangorestframework.views import View
 from djangorestframework.compat import RequestFactory
 from djangorestframework import status

djangorestframework/tests/throttling.py

@@ -45,7 +45,7 @@ class ThrottlingTests(TestCase):
         request = self.factory.get('/')
         for dummy in range(4):
             response = MockView.as_view()(request)
-        self.assertEqual(503, response.status_code)
+        self.assertEqual(429, response.status_code)
 
     def set_throttle_timer(self, view, value):
         """
@@ -62,7 +62,7 @@ class ThrottlingTests(TestCase):
         request = self.factory.get('/')
         for dummy in range(4):
             response = MockView.as_view()(request)
-        self.assertEqual(503, response.status_code)
+        self.assertEqual(429, response.status_code)
 
         # Advance the timer by one second
         self.set_throttle_timer(MockView, 1)
@@ -90,7 +90,7 @@ class ThrottlingTests(TestCase):
         """
         Ensure request rate is limited globally per View for PerViewThrottles
         """
-        self.ensure_is_throttled(MockView_PerViewThrottling, 503)
+        self.ensure_is_throttled(MockView_PerViewThrottling, 429)
 
     def ensure_response_header_contains_proper_throttle_field(self, view, expected_headers):
         """

djangorestframework/views.py

@@ -6,12 +6,14 @@ By setting or modifying class attributes on your view, you change it's predefine
 """
 
 import re
+from django.core.exceptions import PermissionDenied
+from django.http import Http404
 from django.utils.html import escape
 from django.utils.safestring import mark_safe
 from django.views.decorators.csrf import csrf_exempt
 
 from djangorestframework.compat import View as DjangoView, apply_markdown
-from djangorestframework.response import Response, ImmediateResponse
+from djangorestframework.response import Response
 from djangorestframework.request import Request
 from djangorestframework import renderers, parsers, authentication, permissions, status, exceptions
 
@@ -219,13 +221,27 @@ class View(DjangoView):
             response[key] = value
         return response
 
+    def handle_exception(self, exc):
+        """
+        Handle any exception that occurs, by returning an appropriate response,
+        or re-raising the error.
+        """
+        if isinstance(exc, exceptions.REST_FRAMEWORK_EXCEPTIONS):
+            return Response({'detail': exc.detail}, status=exc.status_code)
+        elif isinstance(exc, Http404):
+            return Response({'detail': 'Not found'},
+                            status=status.HTTP_404_NOT_FOUND)
+        elif isinstance(exc, PermissionDenied):
+            return Response({'detail': 'Permission denied'},
+                            status=status.HTTP_403_FORBIDDEN)
+        raise
+
     # Note: session based authentication is explicitly CSRF validated,
     # all other authentication is CSRF exempt.
     @csrf_exempt
     def dispatch(self, request, *args, **kwargs):
         request = Request(request, parsers=self.parsers, authentication=self.authentication)
         self.request = request
-
         self.args = args
         self.kwargs = kwargs
         self.headers = self.default_response_headers
@@ -244,10 +260,8 @@ class View(DjangoView):
 
             response = handler(request, *args, **kwargs)
 
-        except ImmediateResponse, exc:
-            response = exc.response
-        except (exceptions.ParseError, exceptions.PermissionDenied) as exc:
-            response = Response({'detail': exc.detail}, status=exc.status_code)
+        except Exception as exc:
+            response = self.handle_exception(exc)
 
         self.response = self.final(request, response, *args, **kwargs)
         return self.response
@@ -265,4 +279,4 @@ class View(DjangoView):
             for name, field in form.fields.iteritems():
                 field_name_types[name] = field.__class__.__name__
             content['fields'] = field_name_types
-        raise ImmediateResponse(content, status=status.HTTP_200_OK)
+        raise Response(content, status=status.HTTP_200_OK)