Add a new command to get facts for XenAPI

This commit is to add a new command - get_xenapi_facts
which will gather facts for XenAPI. When deploy OpenStack
on XenServer, the facts can be used by deploy approach(e.g.
kolla-ansible).

Change-Id: Ia606d6ddc651cfa0b75fa34d8f14bc156d9dbe27

os_xenapi/utils/xenapi_facts.py

@@ -0,0 +1,52 @@
+#!/usr/bin/env python
+# Copyright 2017 Citrix Systems
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""Utilies for XenAPI facts gathering
+
+It contains utilies to gather XenAPI relative facts."""
+
+import json
+import sys
+
+from os_xenapi.utils import common_function
+from os_xenapi.utils import himn
+from os_xenapi.utils import sshclient
+
+
+def get_hostname(host_client):
+    out, _ = host_client.ssh('hostname')
+    hostname = out.strip()
+    return hostname
+
+
+def get_facts(dom0_himn_ip, user_name, passwd):
+    facts = {}
+
+    dom0_client = sshclient.SSHClient(dom0_himn_ip, user_name, passwd)
+
+    facts['hostname'] = get_hostname(dom0_client)
+
+    # get local HIMN info
+    eth = himn.get_local_himn_eth(dom0_himn_ip)
+    ip_addr = common_function.get_eth_ipaddr(eth)
+    facts['local_himn_eth'] = eth
+    facts['local_himn_ip'] = ip_addr
+
+    return json.dumps(facts)
+
+if __name__ == '__main__':
+    dom0_himn_ip, user_name, passwd = sys.argv[1:]
+    facts_json = get_facts(dom0_himn_ip, user_name, passwd)
+    print('get_facts returns:\n %s' % facts_json)