add rate limiter

metrics/wrapper/listener.go

@@ -0,0 +1,32 @@
+package wrapper
+
+import (
+	"net"
+
+	"github.com/go-gost/core/metrics"
+)
+
+type listener struct {
+	service string
+	net.Listener
+}
+
+func WrapListener(service string, ln net.Listener) net.Listener {
+	if !metrics.IsEnabled() {
+		return ln
+	}
+
+	return &listener{
+		service:  service,
+		Listener: ln,
+	}
+}
+
+func (ln *listener) Accept() (net.Conn, error) {
+	c, err := ln.Listener.Accept()
+	if err != nil {
+		return nil, err
+	}
+
+	return WrapConn(ln.service, c), nil
+}