Defer client loading in Django log handler (fixes GH-701)

raven/contrib/django/handlers.py

@@ -8,13 +8,25 @@ raven.contrib.django.handlers
 
 from __future__ import absolute_import
 
-from raven.contrib.django.models import client
+import logging
+
 from raven.handlers.logging import SentryHandler as BaseSentryHandler
+from raven.utils import memoize
 
 
 class SentryHandler(BaseSentryHandler):
     def __init__(self, *args, **kwargs):
-        super(SentryHandler, self).__init__(client=client, *args, **kwargs)
+        # TODO(dcramer): we'd like to avoid this duplicate code, but we need
+        # to currently defer loading client due to Django loading patterns.
+        self.tags = kwargs.pop('tags', None)
+
+        logging.Handler.__init__(self, level=kwargs.get('level', logging.NOTSET))
+
+    @memoize
+    def client(self):
+        # Import must be lazy for deffered Django loading
+        from raven.contrib.django.models import client
+        return client
 
     def _emit(self, record):
         request = getattr(record, 'request', None)