[zmq] ZMQ_LINGER default value

Set default socket close linger value to -1,
which means wait until all messages being
sent.

Change-Id: I52cabc268a777a6c2505098d0520669389a44766

oslo_messaging/_drivers/impl_zmq.py

@@ -58,9 +58,12 @@ zmq_opts = [
                help='Name of this node. Must be a valid hostname, FQDN, or '
                     'IP address. Must match "host" option, if running Nova.'),
 
-    cfg.IntOpt('rpc_cast_timeout', default=30,
+    cfg.IntOpt('rpc_cast_timeout', default=-1,
                help='Seconds to wait before a cast expires (TTL). '
-                    'Only supported by impl_zmq.'),
+                    'The default value of -1 specifies an infinite linger '
+                    'period. The value of 0 specifies no linger period. '
+                    'Pending messages shall be discarded immediately '
+                    'when the socket is closed. Only supported by impl_zmq.'),
 
     cfg.IntOpt('rpc_poll_timeout', default=1,
                help='The default number of seconds that poll should wait. '

oslo_messaging/_drivers/zmq_driver/zmq_socket.py

@@ -36,6 +36,12 @@ class ZmqSocket(object):
         self.context = context
         self.socket_type = socket_type
         self.handle = context.socket(socket_type)
+
+        self.close_linger = -1
+        if self.conf.rpc_cast_timeout > 0:
+            self.close_linger = self.conf.rpc_cast_timeout * 1000
+        self.handle.setsockopt(zmq.LINGER, self.close_linger)
+
         self.connections = set()
 
     def type_name(self):
@@ -86,7 +92,6 @@ class ZmqSocket(object):
         return self.handle.recv_multipart(*args, **kwargs)
 
     def close(self, *args, **kwargs):
-        self.handle.setsockopt(zmq.LINGER, self.conf.rpc_cast_timeout * 1000)
         self.handle.close(*args, **kwargs)
 
     def connect_to_address(self, address):