haproxy get_stats method is not python3 compatible

[Thomas Herve]

As seen in Heat python3 jobs:

Traceback (most recent call last):
  File "/opt/stack/new/neutron-lbaas/neutron_lbaas/agent/agent_manager.py", line 142, in collect_stats
    stats = driver.loadbalancer.get_stats(loadbalancer_id)
  File "/opt/stack/new/neutron-lbaas/neutron_lbaas/drivers/haproxy/namespace_driver.py", line 460, in get_stats
    return self.driver.get_stats(loadbalancer_id)
  File "/opt/stack/new/neutron-lbaas/neutron_lbaas/drivers/haproxy/namespace_driver.py", line 182, in get_stats
    STATS_TYPE_SERVER_REQUEST))
  File "/opt/stack/new/neutron-lbaas/neutron_lbaas/drivers/haproxy/namespace_driver.py", line 258, in _get_stats_from_socket
    s.send('show stat -1 %s -1\n' % entity_type)
  File "/usr/local/lib/python3.5/dist-packages/eventlet/greenio/base.py", line 384, in send
    return self._send_loop(self.fd.send, data, flags)
  File "/usr/local/lib/python3.5/dist-packages/eventlet/greenio/base.py", line 371, in _send_loop
    return send_method(data, *args)
TypeError: a bytes-like object is required, not 'str'

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/474868

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/474868
Committed: https://git.openstack.org/cgit/openstack/neutron-lbaas/commit/?id=c5a8ed2447ca16729f13b2c9902baa1ac4916280
Submitter: Jenkins
Branch: master

commit c5a8ed2447ca16729f13b2c9902baa1ac4916280
Author: Thomas Herve <email address hidden>
Date: Fri Jun 16 08:59:59 2017 +0200

    Send haproxy stat command as bytes

    The get_stats method on the haproxy driver fails with a byte error,
    let's encode the command before sending it, and decode the result.

    Change-Id: I3ea1ca4ca3216e9411ac761f54f458eea5d736fb
    Closes-Bug: #1698301

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron-lbaas 11.0.0.0rc1 release candidate.