Reconnect to database when encountering PDOExceptions with error code in predefined list

[ZachWatkins]

Howdy! I've solved this problem for a project using a serverless database and wanted to get feedback on whether the framework maintainers would welcome a pull request to provide this as a feature in the DB facade, a helper function, or in some other way.

I can't share the exact code, but I would need to rewrite it in any case to fit better with the implementation requirements.

The code I wrote implemented the process described here: https://learn.microsoft.com/en-us/azure/azure-sql/database/troubleshoot-common-connectivity-issues?view=azuresql-db#retry-logic-for-transient-errors

The way we implemented it allows me to add a list of error codes to ./config/database.php. Whenever a database command is run that I need to only retry when it encounters one of these codes, I wrap it in a helper function I designed to execute the retry logic. It also resets the PDO timeout configuration before the first reattempt of the DB query that failed, and uses exponential backoff for subsequent attempts.

I welcome your feedback!