Add support of proxy protocol

internal/proxyprotocol/adapter.go

@@ -0,0 +1,20 @@
+package proxyprotocol
+
+import (
+	"net"
+
+	"github.com/pires/go-proxyproto"
+)
+
+type ListenerAdapter struct {
+	proxyproto.Listener
+}
+
+func (l *ListenerAdapter) Accept() (net.Conn, error) {
+	conn, err := l.Listener.Accept()
+	if err != nil {
+		return nil, err
+	}
+
+	return connWrapper{conn.(*proxyproto.Conn)}, nil
+}

internal/proxyprotocol/conn.go

@@ -0,0 +1,25 @@
+package proxyprotocol
+
+import "github.com/pires/go-proxyproto"
+
+type connWrapper struct {
+	*proxyproto.Conn
+}
+
+func (c connWrapper) CloseRead() error {
+	tcpConn, ok := c.TCPConn()
+	if !ok {
+		panic("we support only tcp connections")
+	}
+
+	return tcpConn.CloseRead()
+}
+
+func (c connWrapper) CloseWrite() error {
+	tcpConn, ok := c.TCPConn()
+	if !ok {
+		panic("we support only tcp connections")
+	}
+
+	return tcpConn.CloseWrite()
+}