middleware to give json responses for exceptions

oxdjango/middleware.py

@@ -0,0 +1,13 @@
+# -*- coding: utf-8 -*-
+# vi:si:et:sw=4:sts=4:ts=4
+
+from shortcuts import Http404Json, render_to_json_response
+
+class ExceptionMiddleware(object):
+
+  def process_exception(self, request, exception):
+    if isinstance(exception, Http404Json):     
+      return render_to_json_response(exception.response)          
+    else:
+      return None
+

oxdjango/shortcuts.py

@@ -1,13 +1,17 @@
 # -*- coding: utf-8 -*-
 # vi:si:et:sw=4:sts=4:ts=4
 
-from django.http import HttpResponse, Http404
+from django.http import HttpResponse, Http404, HttpResponseNotFound
 try:
     import simplejson
 except ImportError:
     from django.utils import simplejson
 from django.conf import settings
 
+class Http404Json(Http404):
+    def __init__(self, response):
+        self.response = response
+
 def render_to_json_response(dictionary, content_type="text/json", status=200):
     indent=None
     if settings.DEBUG:
@@ -27,6 +31,6 @@ def get_object_or_404_json(klass, *args, **kwargs):
         return queryset.get(*args, **kwargs)
     except queryset.model.DoesNotExist:
         #FIXME: how to raise exception that will only output given result
-        results = simplejson.dumps({'status': {'code': 404,
-            'text': '%s not found' % queryset.model._meta.object_name}})
-        raise Http404(results)
+        response = {'status': {'code': 404,
+            'text': '%s not found' % queryset.model._meta.object_name}}
+        raise Http404Json(response)