Refactored logging of internal server errors. Can now be customized

flask/app.py

@@ -1216,14 +1216,24 @@ class Flask(_PackageBoundObject):
             else:
                 raise e
 
-        self.logger.exception('Exception on %s [%s]' % (
+        self.log_exception((exc_type, exc_value, tb))
-            request.path,
-            request.method
-        ))
         if handler is None:
             return InternalServerError()
         return handler(e)
 
+    def log_exception(self, exc_info):
+        """Logs an exception.  This is called by :meth:`handle_exception`
+        if debugging is disabled and right before the handler is called.
+        The default implementation logs the exception as error on the
+        :attr:`logger`.
+
+        .. versionadded:: 0.8
+        """
+        self.logger.error('Exception on %s [%s]' % (
+            request.path,
+            request.method
+        ), exc_info=exc_info)
+
     def raise_routing_exception(self, request):
         """Exceptions that are recording during routing are reraised with
         this method.  During debug we are not reraising redirect requests