Comment 0 for bug 1496415

Statistics API has changed slightly from it's pre-release state resulting in errors when reading backend capabilities:

2015-09-16 12:08:08.316 4382 DEBUG manila.share.drivers.quobyte.jsonrpc [req-8928dd45-fd90-4fe9-b06a-ca99feb109de ] Retrieved data from Quobyte backend: {u'jsonrpc': u'2.0', u'result': {u'task_counts': [], u'volume_count': 1, u'total_logical_capacity': 0, u'total_physical_capacity': 0, u'decommissioned_device': 0, u'total_physical_usage': 0, u'registered_device_count': 1, u'unavailable_device_count': 0, u'unassociated_device_count': 0, u'total_logical_usage': 0}, u'id': u'2'} call /opt/stack/manila/manila/share/drivers/quobyte/jsonrpc.py:137
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/eventlet/hubs/poll.py", line 115, in wait
    listener.cb(fileno)
  File "/usr/local/lib/python2.7/dist-packages/eventlet/greenthread.py", line 214, in main
    result = function(*args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/oslo_service/service.py", line 645, in run_service
    service.start()
  File "/opt/stack/manila/manila/service.py", line 120, in start
    self.manager.init_host()
  File "/opt/stack/manila/manila/share/manager.py", line 110, in wrapped
    return f(self, *args, **kwargs)
  File "/opt/stack/manila/manila/share/manager.py", line 269, in init_host
    self.publish_service_capabilities(ctxt)
  File "/opt/stack/manila/manila/share/manager.py", line 110, in wrapped
    return f(self, *args, **kwargs)
  File "/opt/stack/manila/manila/share/manager.py", line 1126, in publish_service_capabilities
    self._report_driver_status(context)
  File "/opt/stack/manila/manila/share/manager.py", line 1092, in _report_driver_status
    share_stats = self.driver.get_share_stats(refresh=True)
  File "/opt/stack/manila/manila/share/driver.py", line 614, in get_share_stats
    self._update_share_stats()
  File "/opt/stack/manila/manila/share/drivers/quobyte/quobyte.py", line 99, in _update_share_stats
    total_gb, free_gb = self._get_capacities()
  File "/opt/stack/manila/manila/share/drivers/quobyte/quobyte.py", line 114, in _get_capacities
    total = float(result['statistics']['total_logical_capacity'])
KeyError: 'statistics'