Ticket #3067: better_servername_caching.patch

django/core/mail.py

@@ -8 +8 @@
 import time
 import random
 
-DNS_NAME = socket.getfqdn() # Cache the hostname
+# Cache the hostname, but do it "lazily". `getfqdn` can take a couple of
+# seconds, which slows down the restart of the server (especially noticable
+# on the development server).
+class CacheDnsName(object):
+    def __repr__(self):
+        return self.get_fqdn()
+    def get_fqdn(self):
+        if not hasattr(self, '_fqdn'):
+            self._fqdn = socket.getfqdn()
+        return self._fqdn
+DNS_NAME = CacheDnsName()
 
 class BadHeaderError(ValueError):
     pass