Add unit tests for utils

**Feature request**
It would be great to have logging for handlers.

**Use case**
Many users need this functionality for production deployments.

**Implementation idea**
Add a new config option `enable_logging` with default `false`.

Start by locating the utils and handler code referenced by the issue, then trace how configuration options are defined and read. Confirm the expected logging behavior and add coverage for the new enable_logging option, including its default false value; the unit tests should demonstrate that handler logging follows the option.

Written by the indexing model from the issue text.