Refactor controllers for better readability

**Feature request**
It would be great to have search for config.

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

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

The issue names no files, tests, or entry points. Start by locating the configuration handling and the controller or search-related entry points; done should include an `enable_search` option whose default is `false` and a defined, tested search behavior for configuration.

Written by the indexing model from the issue text.