Bring db setup vars in line with other roles

Allows for galera_db_setup_host to be overridden if necessary for delegation.
Brings the format in line with the db_setup vars in other roles.

Change-Id: Ie2a802ebb8297bed03d74b3cf54907322b858896

defaults/main.yml

@@ -206,6 +206,10 @@ galera_client_my_cnf_overrides: {}
 # "galera_server" group and fall back to localhost.
 galera_ssl_server: "{{ (galera_cluster_members | default(['localhost']))[0] }}"
 
+## Database info
+galera_db_setup_host: "{{ openstack_db_setup_host | default(galera_cluster_members[0] | default('localhost')) }}"
+galera_db_setup_python_interpreter: "{{ openstack_db_setup_python_interpreter | default((galera_db_setup_host == 'localhost') | ternary(ansible_playbook_python, ansible_python['executable'])) }}"
+
 # Configure backups of database
 # copies is the number of full backups to be kept, the corresponding
 # incremental backups will also be kept. Uses systemd timer instead of cron.

tasks/galera_server_backups.yml

@@ -79,12 +79,9 @@
   when: galera_mariadb_backups_increment_on_calendar is defined
 
 - name: Grant access to the database for the backup service
-  delegate_to: "{{ openstack_db_setup_host | default('localhost') }}"
+  delegate_to: "{{ galera_db_setup_host }}"
   vars:
-    galera_db_setup_host: "{{ openstack_db_setup_host | default('localhost') }}"
-    ansible_python_interpreter: "{{ openstack_db_setup_python_interpreter |
-                                 default((galera_db_setup_host == 'localhost') |
-                                 ternary(ansible_playbook_python, ansible_python['executable'])) }}"
+    ansible_python_interpreter: "{{ galera_db_setup_python_interpreter }}"
   community.mysql.mysql_user:
     name: "{{ galera_mariadb_backups_user }}"
     password: "{{ galera_mariadb_backups_password }}"