Wait for nova-compute service registration

A race condition is caused when nova-compute is started for the
first time because it takes a period of time for nova-compute
to spin up, register itself with nova API, and become available for
cell enrollment.

Prior to this there was no wait condition when nova-compute
restarts occurred, so the first time nova-compute started, often
the compute service was not registered in the database and available
for cell enrollment when the enrollment tasks ran.

Change-Id: I510f0a957f53d15affa1fc23f809abff52208438

defaults/main.yml

@@ -457,6 +457,7 @@ nova_requires_pip_packages:
   - virtualenv-tools
   - python-keystoneclient # Keystoneclient needed to OSA keystone lib
   - httplib2
+  - python-openstackclient
 
 nova_compute_pip_packages:
   - libvirt-python

handlers/main.yml

@@ -23,6 +23,7 @@
     name: "{{ item.value.service_name }}"
     state: "restarted"
   with_dict: "{{ nova_services }}"
+  register: nova_service_restart
   when:
     - inventory_hostname in groups[item.value.group]
     - "{{ item.value.condition | default(true) }}"

tasks/main.yml

@@ -85,6 +85,13 @@
 - name: Flush handlers
   meta: flush_handlers
 
+- include: nova_compute_wait.yml
+  when:
+    - "{{ 'nova_compute' in group_names }}"
+    - "{{ nova_service_restart | default(dict(changed=False)) | changed }}"
+  tags:
+    - nova-config
+
 - include: nova_db_post_setup.yml
   when: inventory_hostname == groups['nova_api_os_compute'][0]
   tags:

tasks/nova_compute_wait.yml

@@ -0,0 +1,25 @@
+---
+# Copyright 2017, Logan Vig <logan2211@gmail.com>
+#
+# 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.
+
+- name: Wait for the nova-compute service to initialize
+  command: openstack --os-cloud default compute service list -f json
+  changed_when: false
+  register: nova_service_list
+  retries: 10
+  delay: 5
+  until: "{{ ansible_hostname in (nova_service_list.stdout
+                                  | from_json
+                                  | selectattr('Binary', 'equalto', 'nova-compute')
+                                  | map(attribute='Host') | list) }}"