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backend/app/middleware/api_host_guard.go

@@ -2,10 +2,13 @@ package middleware
 
 import "github.com/gofiber/fiber/v3"
 
-func APIHostGuard(allowedHost string) fiber.Handler {
+func APIHostGuard(allowedHost string, alternativeHandler fiber.Handler) fiber.Handler {
 	return func(c fiber.Ctx) error {
 		if c.Hostname() != allowedHost {
-			return c.Status(fiber.StatusNotFound).SendString("Not Found")
+			if alternativeHandler != nil {
+				return alternativeHandler(c)
+			}
+			return c.Status(fiber.StatusForbidden).SendString("Forbidden: Invalid API host")
 		}
 		return c.Next()
 	}