Clarify setting socket_options

There was a lot of code that would have no effect if kwargs already
had socket_options set. To make the code clearer, only execute the
code if it's going to have an effect.

Change-Id: Ic42f5a0bac07113aff59d36d19293dc6d65cd58a

1 files changed, 24 insertions, 22 deletions

diff --git a/keystoneclient/session.py b/keystoneclient/session.py
index a3c7a6f..cace4f7 100644
--- a/keystoneclient/session.py
+++ b/keystoneclient/session.py
@@ -906,28 +906,30 @@ class TCPKeepAliveAdapter(requests.adapters.HTTPAdapter):
     http://blogs.msdn.com/b/windowsazurestorage/archive/2010/06/25/nagle-s-algorithm-is-not-friendly-towards-small-requests.aspx
     """
     def init_poolmanager(self, *args, **kwargs):
-        socket_options = [
-            # Keep Nagle's algorithm off
-            (socket.IPPROTO_TCP, socket.TCP_NODELAY, 1),
-            # Turn on TCP Keep-Alive
-            (socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1),
-            # Set the maximum number of keep-alive probes
-            (socket.IPPROTO_TCP, socket.TCP_KEEPCNT, 4),
-            # Send keep-alive probes every 15 seconds
-            (socket.IPPROTO_TCP, socket.TCP_KEEPINTVL, 15),
-        ]
-
-        # Some operating systems (e.g., OSX) do not support setting
-        # keepidle
-        if hasattr(socket, 'TCP_KEEPIDLE'):
-            socket_options += [
-                # Wait 60 seconds before sending keep-alive probes
-                (socket.IPPROTO_TCP, socket.TCP_KEEPIDLE, 60)
+        if 'socket_options' not in kwargs:
+            socket_options = [
+                # Keep Nagle's algorithm off
+                (socket.IPPROTO_TCP, socket.TCP_NODELAY, 1),
+                # Turn on TCP Keep-Alive
+                (socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1),
+                # Set the maximum number of keep-alive probes
+                (socket.IPPROTO_TCP, socket.TCP_KEEPCNT, 4),
+                # Send keep-alive probes every 15 seconds
+                (socket.IPPROTO_TCP, socket.TCP_KEEPINTVL, 15),
             ]
 
-        # After waiting 60 seconds, and then sending a probe once every 15
-        # seconds 4 times, these options should ensure that a connection
-        # hands for no longer than 2 minutes before a ConnectionError is
-        # raised.
-        kwargs.setdefault('socket_options', socket_options)
+            # Some operating systems (e.g., OSX) do not support setting
+            # keepidle
+            if hasattr(socket, 'TCP_KEEPIDLE'):
+                socket_options += [
+                    # Wait 60 seconds before sending keep-alive probes
+                    (socket.IPPROTO_TCP, socket.TCP_KEEPIDLE, 60)
+                ]
+
+            # After waiting 60 seconds, and then sending a probe once every 15
+            # seconds 4 times, these options should ensure that a connection
+            # hands for no longer than 2 minutes before a ConnectionError is
+            # raised.
+
+            kwargs['socket_options'] = socket_options
         super(TCPKeepAliveAdapter, self).init_poolmanager(*args, **kwargs)