Add unit tests for utils

**Feature request**
It would be great to have compression for controllers.

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

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

Start by reconciling the title, which asks for unit tests for utils, with the body, which requests controller compression and an enable_compression configuration option. Locate the controller, configuration, and utility entry points, then review existing tests. Done means the requested behavior and default setting are covered by tests, with the intended scope confirmed in the issue thread.

Written by the indexing model from the issue text.