Move database creation into role

There is no record for why we implement the database creation outside
of the role in the playbook, when we could do it inside the role.

Implementing it inside the role allows us to reduce the quantity of
group_vars duplicated from the role, and allows us to better document
the required variables in the role. The delegation can still be done
as it is done in the playbook too.

In this patch we implement a new variable called 'gnocchi_db_setup_host'
which is used in the role to allow delegation of the database setup
task to any host, but defaults to the first member of the galera_all
host group. We also document the variable gnocchi_galera_address which
has been used for a long time, but never documented.

Change-Id: Idff20080d825e5afd071cbc03055f96c920aff9d

defaults/main.yml

@@ -67,6 +67,8 @@ gnocchi_venv_download: "{{ not gnocchi_developer_mode | bool and not gnocchi_ide
 gnocchi_venv_download_url: http://127.0.0.1/venvs/untagged/ubuntu/gnocchi.tgz
 
 #: Index Database info
+gnocchi_db_setup_host: "{{ ('galera_all' in groups) | ternary(groups['galera_all'][0], 'localhost') }}"
+gnocchi_galera_address: "{{ galera_address | default('127.0.0.1') }}"
 gnocchi_galera_database: gnocchi
 gnocchi_galera_user: gnocchi
 gnocchi_galera_address: "{{ galera_address }}"

examples/playbook.yml

@@ -3,3 +3,7 @@
   user: root
   roles:
     - { role: "os_gnocchi", tags: [ "os-gnocchi" ] }
+    galera_root_user: root
+  vars_prompt:
+    - name: "galera_root_password"
+      prompt: "What is galera_root_password?"

tasks/gnocchi_db_setup.yml

@@ -13,6 +13,32 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+- name: Create DB for service
+  mysql_db:
+    login_user: "{{ galera_root_user }}"
+    login_password: "{{ galera_root_password }}"
+    login_host: "{{ gnocchi_galera_address }}"
+    name: "{{ gnocchi_galera_database }}"
+    state: "present"
+  delegate_to: "{{ gnocchi_db_setup_host }}"
+  no_log: True
+
+- name: Grant access to the DB for the service
+  mysql_user:
+    login_user: "{{ galera_root_user }}"
+    login_password: "{{ galera_root_password }}"
+    login_host: "{{ gnocchi_galera_address }}"
+    name: "{{ gnocchi_galera_user }}"
+    password: "{{ gnocchi_container_mysql_password }}"
+    host: "{{ item }}"
+    state: "present"
+    priv: "{{ gnocchi_galera_database }}.*:ALL"
+  delegate_to: "{{ gnocchi_db_setup_host }}"
+  with_items:
+    - "localhost"
+    - "%"
+  no_log: True
+
 - name: Perform a Gnocchi DB sync
   command: "{{ gnocchi_bin }}/gnocchi-upgrade {{ gnocchi_db_sync_options }}"
   become: yes