How to intercept a request by a microservice?

Question

symfony

Perhaps there is a name for this. I want to transfer part of the functionality responsible for security checks to a separate microservice (guard). Put it in front of the main service that will do the rest of the work. In guard, I receive a request with data, check the data but do not change it in any way, but simply pass it on or give an error if the data is not correct.

What is this approach called and how to implement it in Symphony? HttpClient Symfony cannot simply take and pass the received request, there you need to manually form a request, receive a response and send it to the client. How about sooner?)