Swift MemcacheConnPool does not support IPv6

[Timur Alperovich]

In the MemcacheConnPool there is an implicit assumption that the configured IPs are all v4. Specifically, the create() method is buggy for v6:

def create(self):
    if ':' in self.server:
        host, port = self.server.split(':')
    else:
        host = self.server
        port = DEFAULT_MEMCACHED_PORT
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
    with Timeout(self._connect_timeout):
        sock.connect((host, int(port)))
    return (sock.makefile(), sock)

The method should be rewritten to reason correctly about IPv6 addresses.

[Timur Alperovich (timur-alperovich)]

Proposed a patch to fix this: https://review.openstack.org/#/c/258704/

[Timur Alperovich (timur-alperovich)]

Patch was merged and this is resolved.