adds the config_template to nova

The change modifies the nova template tasks such that it's now
using the config_template action plugin. This change will make so that
config files can be dynamically updated, by a deployer, at run time,
without requiring the need to modify the in tree templates or defaults.

Partially implements: blueprint tunable-openstack-configuration

Change-Id: I9842ed3fcb2cc4aa379a582359b1ca5d0747f714

playbooks/roles/os_nova/defaults/main.yml

@@ -335,3 +335,10 @@ nova_pip_packages:
   - python-novaclient
   - keystonemiddleware
   - nova
+
+
+## Tunable overrides
+nova_nova_conf_overrides: {}
+nova_rootwrap_conf_overrides: {}
+nova_api_paste_ini_overrides: {}
+nova_policy_overrides: {}

playbooks/roles/os_nova/tasks/nova_post_install.yml

@@ -13,6 +13,37 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+- name: Copy nova config
+  config_template:
+    src: "{{ item.src }}"
+    dest: "{{ item.dest }}"
+    owner: "{{ nova_system_user_name }}"
+    group: "{{ nova_system_group_name }}"
+    mode: "0644"
+    config_overrides: "{{ item.config_overrides }}"
+    config_type: "{{ item.config_type }}"
+  with_items:
+    - src: "nova.conf.j2"
+      dest: "/etc/nova/nova.conf"
+      config_overrides: "{{ nova_nova_conf_overrides }}"
+      config_type: "ini"
+    - src: "rootwrap.conf.j2"
+      dest: "/etc/nova/rootwrap.conf"
+      config_overrides: "{{ nova_rootwrap_conf_overrides }}"
+      config_type: "ini"
+    - src: "api-paste.ini.j2"
+      dest: "/etc/nova/api-paste.ini"
+      config_overrides: "{{ nova_api_paste_ini_overrides }}"
+      config_type: "ini"
+    - src: "policy.json.j2"
+      dest: "/etc/nova/policy.json"
+      config_overrides: "{{ nova_policy_overrides }}"
+      config_type: "json"
+  notify: Restart nova services
+  tags:
+    - nova-config
+    - nova-post-install
+
 - name: Generate nova config
   copy:
     src: "{{ item.src }}"
@@ -20,42 +51,12 @@
     owner: "{{ nova_system_user_name }}"
     group: "{{ nova_system_group_name }}"
   with_items:
-    - { src: "rootwrap.conf", dest: "/etc/nova/rootwrap.conf" }
     - { src: "rootwrap.d/api-metadata.filters", dest: "/etc/nova/rootwrap.d/api-metadata.filters" }
     - { src: "rootwrap.d/baremetal-compute-ipmi.filters", dest: "/etc/nova/rootwrap.d/baremetal-compute-ipmi.filters" }
     - { src: "rootwrap.d/baremetal-deploy-helper.filters", dest: "/etc/nova/rootwrap.d/baremetal-deploy-helper.filters" }
     - { src: "rootwrap.d/compute.filters", dest: "/etc/nova/rootwrap.d/compute.filters" }
     - { src: "rootwrap.d/network.filters", dest: "/etc/nova/rootwrap.d/network.filters" }
-    - { src: "api-paste.ini", dest: "/etc/nova/api-paste.ini" }
   notify: Restart nova services
   tags:
     - nova-config
     - nova-post-install
-
-- name: Copy nova config
-  template:
-    src: "{{ item.src }}"
-    dest: "{{ item.dest }}"
-    owner: "{{ nova_system_user_name }}"
-    group: "{{ nova_system_group_name }}"
-  with_items:
-    - { src: "nova.conf.j2", dest: "/etc/nova/nova.conf" }
-  notify: Restart nova services
-  tags:
-    - nova-config
-    - nova-post-install
-
-- name: Apply updates to Policy file
-  config_template:
-    src: "policy.json"
-    dest: "/etc/nova/policy.json"
-    owner: "{{ nova_system_user_name }}"
-    group: "{{ nova_system_group_name }}"
-    mode: "0644"
-    config_overrides: "{{ nova_policy_overrides|default({}) }}"
-    config_type: "json"
-  notify:
-    - Restart nova services
-  tags:
-    - nova-config
-    - nova-post-install