XenAPI: centralize the facts files

When bootstrap compute hosts for XenAPI, it will generate a facts
file for each compute node. It contains some XenAPI specific variables
for both the compute host and the XenServer where the compute host
run on. This commit is to fetch the facts file into deployment host
and put it under a centralized directory - each compute host will
have a separate sub-dir which is named with its *inventory_hostname*.

In this way, the following tasks can use proper variable from the
proper facts file which exactly belongs to the host they running on.

Change-Id: I68d1a2d098d38c8e6bf4db76cdaf1f0465831822
blueprint: xenserver-support

ansible/group_vars/all.yml

@@ -736,7 +736,8 @@ xenserver_himn_ip: "169.254.0.1"
 xenserver_username: "root"
 xenserver_connect_protocol: "https"
 # File used to save XenAPI's facts variables formatted as json.
-xenapi_facts_file: "/etc/kolla/xenapi.json"
+xenapi_facts_root: "/etc/kolla/xenapi/"
+xenapi_facts_file: "facts.json"
 
 #############################################
 # MariaDB component-specific database details

ansible/roles/neutron/tasks/config.yml

@@ -149,7 +149,7 @@
     service_name: "{{ item.key }}"
     services_need_ml2_conf_ini:
       - "neutron-openvswitch-agent-xenapi"
-    os_xenapi_variables: "{{ lookup('file', xenapi_facts_file) | from_json }}"
+    os_xenapi_variables: "{{ lookup('file', xenapi_facts_root + '/' + inventory_hostname + '/' + xenapi_facts_file) | from_json }}"
   merge_configs:
     sources:
       - "{{ role_path }}/templates/ml2_conf.ini.j2"

ansible/roles/nova/tasks/bootstrap_xenapi.yml

@@ -4,6 +4,22 @@
     state: present
   become: True
 
-- name: Bootstrap XenAPI compute node
-  command: xenapi_bootstrap -i {{ xenserver_himn_ip }} -u {{ xenserver_username }} -p {{ xenserver_password }} -f {{ xenapi_facts_file }}
+- name: Ensure XenAPI root path
+  file:
+    path: "{{ xenapi_facts_root }}"
+    state: directory
+    mode: "0770"
+  become: True
+
+- name: Bootstrap XenAPI compute node
+  vars:
+    xenapi_facts_path: "{{ xenapi_facts_root + '/' + xenapi_facts_file }}"
+  command: xenapi_bootstrap -i {{ xenserver_himn_ip }} -u {{ xenserver_username }} -p {{ xenserver_password }} -f {{ xenapi_facts_path }}
+  become: True
+
+- name: Fetching XenAPI facts file
+  fetch:
+    src: "{{ xenapi_facts_root + '/' + xenapi_facts_file }}"
+    dest: "{{ xenapi_facts_root + '/' + inventory_hostname + '/' }}"
+    flat: yes
   become: True