Add unit tests for routes

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

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

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

Start by locating the route-handling entry point and the configuration definition; no files or tests are named in the issue. Trace how route responses are produced and how configuration defaults are applied. Done means unit tests cover compression and verify that enable_compression defaults to false.

Written by the indexing model from the issue text.