How to design a server to server notification handler

For a gaming project I have to write PHP scripts that handle notifications from a third party service. Notifications are sent to a specific endpoint via an HTTP request. I receive among other informations codes (ex: 23, 12,10, - more than 20 statuses exists). Each code should trigger very different operations (database query, HTTP request ...) in my system.

Is there a way to write a clean code that handles it respects SOLID principles ?

Here is my reflexion now :

• A class that receive the notifications
• One class per code implementing a common interface