How to run a code before route execution - Laravel 5

Is it a way to run a code before route execution in Laravel 5?

Actually, when I put some code in my api.php file exactly before a route definition, It works, but I want to do this with something like a middleware and assign it to a group of routes for example.

I mean blow code result is exactly what I want but I don't want to put my codes in api.php or web.php.

Needs to say, the middlewares execute after routes initialization.

via Chebli Mohamed