Added some small notes.

src/Service/Router.php

@@ -6,6 +6,11 @@ namespace App\Service;
 use App\Entity\Route;
 use Closure;
 
+/*
+ * A small router implementation for the address book demo.
+ * Currently it doesn't handle GET requests, as not needed.
+ * But if I reuse the code in my bind Api I'll enable GET as well.
+ */
 class Router
 {
     private array $routes;
@@ -31,6 +36,10 @@ class Router
         $this->routes[] = $route;
     }
 
+    /*
+     * Check is there is a known route and executed the callback.
+     * Currently no 404 handling.
+     */
     public function handleRouting(): void
     {
         $requestUri = $_SERVER['REQUEST_URI'];
@@ -48,6 +57,7 @@ class Router
                 return;
             }
         }
+        // Throw a 404 result later …
         die("Invalid route: $requestUri");
     }
 }