From b5523bcc7ddab97620fd7b49e385b44c664ca899 Mon Sep 17 00:00:00 2001 From: Andy Freeland Date: Fri, 6 Sep 2013 11:40:34 -0500 Subject: [PATCH 1/2] Support customizable view EXCEPTION_HANDLER Add `api_settings.EXCEPTION_HANDLER` to support custom error responses. Fixes #907. --- docs/api-guide/settings.md | 16 +++++++++++- rest_framework/settings.py | 4 +++ rest_framework/tests/test_views.py | 41 ++++++++++++++++++++++++++++++ rest_framework/views.py | 2 +- 4 files changed, 61 insertions(+), 2 deletions(-) diff --git a/docs/api-guide/settings.md b/docs/api-guide/settings.md index 542e8c5fa..13f96f9a3 100644 --- a/docs/api-guide/settings.md +++ b/docs/api-guide/settings.md @@ -25,7 +25,7 @@ If you need to access the values of REST framework's API settings in your projec you should use the `api_settings` object. For example. from rest_framework.settings import api_settings - + print api_settings.DEFAULT_AUTHENTICATION_CLASSES The `api_settings` object will check for any user-defined settings, and otherwise fall back to the default values. Any setting that uses string import paths to refer to a class will automatically import and return the referenced class, instead of the string literal. @@ -339,6 +339,20 @@ Default: `'rest_framework.views.get_view_description'` ## Miscellaneous settings +#### EXCEPTION_HANDLER + +A string representing the function that should be used when returning a response for any given exception. If the function returns `None`, a 500 error will be raised. + +This setting can be changed to support error responses other than the default `{"detail": "Failure..."}` responses. For example, you can use it to provide API responses like `{"errors": [{"message": "Failure...", "code": ""} ...]}`. + +This should be a function with the following signature: + + exception_handler(exc) + +* `exc`: The exception. + +Default: `'rest_framework.views.exception_handler'` + #### FORMAT_SUFFIX_KWARG The name of a parameter in the URL conf that may be used to provide a format suffix. diff --git a/rest_framework/settings.py b/rest_framework/settings.py index 8c0847512..8abaf1409 100644 --- a/rest_framework/settings.py +++ b/rest_framework/settings.py @@ -77,6 +77,9 @@ DEFAULTS = { 'VIEW_NAME_FUNCTION': 'rest_framework.views.get_view_name', 'VIEW_DESCRIPTION_FUNCTION': 'rest_framework.views.get_view_description', + # Exception handling + 'EXCEPTION_HANDLER': 'rest_framework.views.exception_handler', + # Testing 'TEST_REQUEST_RENDERER_CLASSES': ( 'rest_framework.renderers.MultiPartRenderer', @@ -125,6 +128,7 @@ IMPORT_STRINGS = ( 'DEFAULT_MODEL_SERIALIZER_CLASS', 'DEFAULT_PAGINATION_SERIALIZER_CLASS', 'DEFAULT_FILTER_BACKENDS', + 'EXCEPTION_HANDLER', 'FILTER_BACKEND', 'TEST_REQUEST_RENDERER_CLASSES', 'UNAUTHENTICATED_USER', diff --git a/rest_framework/tests/test_views.py b/rest_framework/tests/test_views.py index c0bec5aed..65c7e50ea 100644 --- a/rest_framework/tests/test_views.py +++ b/rest_framework/tests/test_views.py @@ -32,6 +32,16 @@ def basic_view(request): return {'method': 'PATCH', 'data': request.DATA} +class ErrorView(APIView): + def get(self, request, *args, **kwargs): + raise Exception + + +@api_view(['GET']) +def error_view(request): + raise Exception + + def sanitise_json_error(error_dict): """ Exact contents of JSON error messages depend on the installed version @@ -99,3 +109,34 @@ class FunctionBasedViewIntegrationTests(TestCase): } self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST) self.assertEqual(sanitise_json_error(response.data), expected) + + +class TestCustomExceptionHandler(TestCase): + def setUp(self): + self.DEFAULT_HANDLER = api_settings.EXCEPTION_HANDLER + + def exception_handler(exc): + return Response('Error!', status=status.HTTP_400_BAD_REQUEST) + + api_settings.EXCEPTION_HANDLER = exception_handler + + def tearDown(self): + api_settings.EXCEPTION_HANDLER = self.DEFAULT_HANDLER + + def test_class_based_view_exception_handler(self): + view = ErrorView.as_view() + + request = factory.get('/', content_type='application/json') + response = view(request) + expected = 'Error!' + self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST) + self.assertEqual(response.data, expected) + + def test_function_based_view_exception_handler(self): + view = error_view + + request = factory.get('/', content_type='application/json') + response = view(request) + expected = 'Error!' + self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST) + self.assertEqual(response.data, expected) diff --git a/rest_framework/views.py b/rest_framework/views.py index 4cff04224..853e64614 100644 --- a/rest_framework/views.py +++ b/rest_framework/views.py @@ -361,7 +361,7 @@ class APIView(View): else: exc.status_code = status.HTTP_403_FORBIDDEN - response = exception_handler(exc) + response = self.settings.EXCEPTION_HANDLER(exc) if response is None: raise From bae0ef6b5dcb0abf2be865340e5476aeab5ce137 Mon Sep 17 00:00:00 2001 From: Andy Freeland Date: Fri, 6 Sep 2013 13:57:32 -0500 Subject: [PATCH 2/2] Add EXCEPTION_HANDLER docs to exception docs --- docs/api-guide/exceptions.md | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/docs/api-guide/exceptions.md b/docs/api-guide/exceptions.md index 8b3e50f1e..fa5053dfe 100644 --- a/docs/api-guide/exceptions.md +++ b/docs/api-guide/exceptions.md @@ -30,9 +30,27 @@ Might receive an error response indicating that the `DELETE` method is not allow HTTP/1.1 405 Method Not Allowed Content-Type: application/json; charset=utf-8 Content-Length: 42 - + {"detail": "Method 'DELETE' not allowed."} +## Custom exception handling + +To implement custom exception handling (e.g. to handle additional exception classes or to override the error response format), create an exception handler function with the following signature: + + exception_handler(exc) + +* `exc`: The exception. + +If the function returns `None`, a 500 error will be raised. + +The exception handler is set globally, using the `EXCEPTION_HANDLER` setting. For example: + + 'EXCEPTION_HANDLER': 'project.app.module.function' + +If not specified, this setting defaults to the exception handler described above: + + 'EXCEPTION_HANDLER': 'rest_framework.views.exception_handler' + --- # API Reference