This is how you import routes from a specific controller (only works if you used annotations):
whatever_routes:
resource: "@MyBundle/Controller/WhateverController.php"
type: annotation
This is very useful if you have multiple controllers in single bundle but you can’t import the whole Controller directory at once because some routes have to be treated in a special way, e.g. you want a different prefix for every controller.
whatever_routes:
resource: "@MyBundle/Controller/WhateverController.php"
prefix: /some-bundle/whatever
type: annotation
other_routes:
resource: "@MyBundle/Controller/AnotherController.php"
prefix: /some-bundle/another
type: annotation
For reference, this is the original documentation of that feature.