From: Alina Quereilhac <alina.quereilhac@inria.fr>
Date: Sat, 12 May 2012 11:54:55 +0000 (+0200)
Subject: Added a hostbyname cache to src/nepi/util/server.py, to reduce the number of dns... 
X-Git-Tag: nepi-3.0.0~163^2~3
X-Git-Url: http://git.onelab.eu/?a=commitdiff_plain;h=b6c84446274af5fd3509b6c63c6c54fec0a263f2;p=nepi.git

Added a hostbyname cache to src/nepi/util/server.py, to reduce the number of dns requests emitted.
---

diff --git a/src/nepi/util/server.py b/src/nepi/util/server.py
index 6ce11768..c53cc4e3 100644
--- a/src/nepi/util/server.py
+++ b/src/nepi/util/server.py
@@ -41,6 +41,8 @@ else:
 
 SHELL_SAFE = re.compile('^[-a-zA-Z0-9_=+:.,/]*$')
 
+hostbyname_cache = dict()
+
 def openssh_has_persist():
     global OPENSSH_HAS_PERSIST
     if OPENSSH_HAS_PERSIST is None:
@@ -569,9 +571,14 @@ def _make_server_key_args(server_key, host, port, args):
         host = '%s:%s' % (host,port)
     # Create a temporary server key file
     tmp_known_hosts = tempfile.NamedTemporaryFile()
-    
+   
+    hostbyname = hostbyname_cache.get(host)
+    if not hostbyname:
+        hostbyname = socket.gethostbyname(host)
+        hostbyname_cache[host] = hostbyname
+
     # Add the intended host key
-    tmp_known_hosts.write('%s,%s %s\n' % (host, socket.gethostbyname(host), server_key))
+    tmp_known_hosts.write('%s,%s %s\n' % (host, hostbyname, server_key))
     
     # If we're not in strict mode, add user-configured keys
     if os.environ.get('NEPI_STRICT_AUTH_MODE',"").lower() not in ('1','true','on'):