Tempest rest clients does not send the accept header for GET and DELETE

[Andrea Frittoli]

Tempest rest client and all clients which rely on it do not send the accept header for GET and DELETE.

The header is aggregated to the content-type one, so it is sent only when the content-type one is needed, which is in case of POST and PUT only.

In case of rate limiting for instance, the returned content-type will be the wrong one for XML (assuming that JSON is the default returned when the header is not specified).

[Mauro S M Rodrigues (maurorodrigues)]

tempest.services.compute.xml.servers_client.ServersClientXML does use Accept header, debuging list_servers I can see:

> /opt/stack/tempest/tempest/services/compute/xml/servers_client.py(239)list_servers()
    238
--> 239 resp, body = self.get(url, self.headers)
    240 servers = self._parse_array(etree.fromstring(body))

pdb> self.headers
{'Content-Type': 'application/xml', 'Accept': 'application/xml', 'X-Auth-Token': <ommiting>}

and the response:

> /opt/stack/tempest/tempest/services/compute/xml/servers_client.py(240)list_servers()
    239 resp, body = self.get(url, self.headers)
--> 240 servers = self._parse_array(etree.fromstring(body))
    241 return resp, {"servers": servers}
ipdb> resp
{'status': '200', 'content-length': '515', 'content-location': u'http://9.114.111.27:8774/v2/5ec615f57dcb4419ad5a0f3ff570a6cc/servers', 'x-compute-request-id': 'req-01e2c636-a791-4036-ba58-46be4f34b9ed', 'connection': 'close', 'date': 'Thu, 12 Dec 2013 14:04:53 GMT', 'content-type': 'application/xml'}
ipdb> body
'<?xml version=\'1.0\' encoding=\'UTF-8\'?>\n<servers xmlns:atom="http://www.w3.org/2005/Atom" xmlns="http://docs.openstack.org/compute/api/v1.1"><server name="server-tempest-1339459178" id="9f72e9c3-2547-42e3-8504-5c76d7ba7c4e"><atom:link href="http://9.114.111.27:8774/v2/5ec615f57dcb4419ad5a0f3ff570a6cc/servers/9f72e9c3-2547-42e3-8504-5c76d7ba7c4e" rel="self"/><atom:link href="http://9.114.111.27:8774/5ec615f57dcb4419ad5a0f3ff570a6cc/servers/9f72e9c3-2547-42e3-8504-5c76d7ba7c4e" rel="bookmark"/></server></servers>'

came in xml as expected.