Modified exception handler to throw django error page in case of 500 error (#4172)

Show Traceback HTML in browsable API

rest_framework/views.py

@@ -3,13 +3,17 @@ Provides an APIView class that is the base of all views in REST framework.
 """
 from __future__ import unicode_literals
 
+import sys
+
+from django.conf import settings
 from django.core.exceptions import PermissionDenied
 from django.db import models
 from django.http import Http404
-from django.http.response import HttpResponseBase
+from django.http.response import HttpResponse, HttpResponseBase
 from django.utils import six
 from django.utils.encoding import smart_text
 from django.utils.translation import ugettext_lazy as _
+from django.views import debug
 from django.views.decorators.csrf import csrf_exempt
 from django.views.generic import View
 
@@ -91,7 +95,11 @@ def exception_handler(exc, context):
         set_rollback()
         return Response(data, status=status.HTTP_403_FORBIDDEN)
 
-    # Note: Unhandled exceptions will raise a 500 error.
+    # throw django's error page if debug is True
+    if settings.DEBUG:
+        exception_reporter = debug.ExceptionReporter(context.get('request'), *sys.exc_info())
+        return HttpResponse(exception_reporter.get_traceback_html(), status=500)
+
     return None