代理数据包时如何使请求与响应匹配？

I'm working on MySQL proxy with browser based GUI. Core of an app looks like:

//Trying to connect to server
rightConn, err := net.Dial("tcp", l.rightAddr)
if err != nil {
    return
}
defer rightConn.Close()

wg.Add(2)
//Start passing packets from client to server
go func() {
    defer wg.Done()
    l.Pipe(leftConn, rightConn)
}()

//Start passing packets from server to client
go func() {
    defer wg.Done()
    l.Pipe(rightConn, leftConn)
}()
wg.Wait()

And here's definition of Pipe:

func (l *Lottip) Pipe(right, left net.Conn) {
for {
    pkt, err := mysql.ReadPacket(right)
    if err != nil {
        break
    }

    if _, err = mysql.WritePacket(pkt, left); err != nil {
        break
    }
}

}

The reason i'm using my custom proxy function instead of

go io.Copy(left, right)
go io.Copy(right, left)

is i have to parse each MySQL's Request/Response packet and prepare it for further processing.

As we all know MySQL client can send a lot of queries and get responses in random order.

The problem is i cannot get how to match request to it's response. While i'm piping using 2 goroutines(1 per direction) i can easily read server response but i don't know to what request it responding.

I've examined request/response between MySQL client and server via Wireshark and found no mention for packet_id or query_id or similar