Occasional mariadb connection issues

[jmcarson]

OperationalError at /accounts/drupal_oauth_provider/login/
(2006, '')

This is typically caused by the mariadb connection in django no longer being active when used.

Possibly caused by our recent upgrade. Look into connection time mismatch between mariadb and django and consider implementing health checks:

https://docs.djangoproject.com/en/4.2/ref/databases/#persistent-database-connections

[jmcarson]

Investigation. We have the following in production.py and no override in .env
DATABASES["default"]["CONN_MAX_AGE"] = env.int("CONN_MAX_AGE", default=60)
The wait timeout for our mariadb is much higher:
SHOW VARIABLES LIKE 'wait_timeout';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| wait_timeout | 28800 |

This setting may have an impact:
| thread_pool_idle_timeout | 60 |

This may have changed during our recent mariadb upgrade. Options are to:

• decrease CONN_MAX_AGE to less than 60
• implement CONN_HEALTH_CHECKS - added in django 4.1