Fix MySQL access denied error during upgrade

This change makes it so that if preconfigured database users are used,
the attempt to change the log_bin_trust_function_creators mysql
variable isn't made anymore.

Also updated the upgrade docs

Change-Id: I356313952d435de6d3b5444c0dd8a71f45aee452
Closes-Bug: 1748269

ansible/roles/glance/tasks/bootstrap_service.yml

@@ -13,6 +13,8 @@
       value: 1
   run_once: True
   delegate_to: "{{ groups[glance_api.group][0] }}"
+  when:
+    - not use_preconfigured_databases | bool
 
 - name: Running Glance bootstrap container
   vars:
@@ -47,3 +49,5 @@
       value: 0
   run_once: True
   delegate_to: "{{ groups[glance_api.group][0] }}"
+  when:
+    - not use_preconfigured_databases | bool

ansible/roles/keystone/tasks/upgrade.yml

@@ -12,7 +12,9 @@
       variable: log_bin_trust_function_creators
       value: 1
   run_once: True
-  when: inventory_hostname == groups['keystone'][0]
+  when:
+    - inventory_hostname == groups['keystone'][0]
+    - not use_preconfigured_databases | bool
 
 - name: Init keystone database upgrade
   command: /bin/true
@@ -38,5 +40,6 @@
       variable: log_bin_trust_function_creators
       value: 0
   run_once: True
-  when: inventory_hostname == groups['keystone'][-1]
-
+  when:
+    - inventory_hostname == groups['keystone'][-1]
+    - not use_preconfigured_databases | bool

doc/source/reference/external-mariadb-guide.rst

@@ -156,6 +156,11 @@ Within ``/etc/kolla/globals.yml``, set the following:
 
 .. end
 
+.. note:: Please note that when the ``use_preconfigured_databases`` flag
+  is set to ``"yes"``, you need to have the ``log_bin_trust_function_creators``
+  mysql variable set to ``1`` by your database administrator before running the
+  ``upgrade`` command.
+
 Using External MariaDB with separated, preconfigured users and databases
 ------------------------------------------------------------------------
 

doc/source/user/operating-kolla.rst

@@ -63,6 +63,10 @@ Then run the command to upgrade::
   does not work at all. This is acceptable because KVM is the recommended
   virtualization driver to use with Nova.
 
+.. note:: Please note that when the ``use_preconfigured_databases`` flag is
+  set to ``"yes"``, you need to have the ``log_bin_trust_function_creators``
+  set to ``1`` by your database administrator before performing the upgrade.
+
 
 Tips and Tricks
 ===============