Problem with nbconn.NetConn

[mhkarimi1383]

I know that this problem is not fully related to this project, but I need help with my problem

func GetRawConnection() (net.Conn, error) {
	conn, err := writePools[rand.Intn(len(writePools))].Acquire(context.Background())
	if err != nil {
		return nil, err
	}
	return conn.Conn().PgConn().Conn(), nil
}

and use it as a normal TCPConn but I'm getting following error

panic: interface conversion: net.Conn is *nbconn.NetConn, not *net.TCPConn

Also I cannot use nbconn.NetConn since it's in internal module also conn property is not public

here is my code that is code that uses GetRawConnection

func handleClient(cliConn *net.TCPConn) {
	defer cliConn.Close()

	serverConn, err := connection.GetRawConnection()
	if err != nil {
		log.Printf("Failed to connect to server: %s", err)
		return
	}
	defer serverConn.Close()
	fmt.Printf("Type of cliConn: %T\n", cliConn)
	fmt.Printf("Type of serverConn: %T\n", serverConn)
	// Proxy(serverConn.(*net.TCPConn), cliConn)
	Proxy(serverConn.(*net.TCPConn), cliConn)
}

func Proxy(srvConn, cliConn *net.TCPConn) {
	serverClosed := make(chan struct{}, 1)
	clientClosed := make(chan struct{}, 1)
	// backend := pgproto3.NewBackend(cliConn, cliConn)

	// startupMsg, err := backend.ReceiveStartupMessage()
	// if err != nil {
	// 	log.Fatal(err)
	// }
	// backend.SetAuthType(pgproto3.AuthTypeMD5Password)

	// switch startupMsg.(type) {
	// case *pgproto3.StartupMessage:
	//	_, err := cliConn.Write((&pgproto3.AuthenticationMD5Password{
	//		Salt: types.MD5AuthSalt,
	//	}).Encode(nil))
	//	if err != nil {
	//		log.Fatal(err)
	//	}
	//}

	go broker(srvConn, cliConn, clientClosed)
	go broker(cliConn, srvConn, serverClosed)

	var waitFor chan struct{}
	select {
	case <-clientClosed:
		srvConn.SetLinger(0)
		srvConn.CloseRead()
		waitFor = serverClosed
	case <-serverClosed:
		cliConn.CloseRead()
		waitFor = clientClosed
	}

	<-waitFor
}

func broker(dst, src net.Conn, srcClosed chan struct{}) {
	_, err := copyBuffer(dst, src, nil)
	if err != nil {
		log.Printf("Copy error: %s", err)
	}
	if err := src.Close(); err != nil {
		log.Printf("Close error: %s", err)
	}
	srcClosed <- struct{}{}
}

Thanks

[jackc]

I'm not sure exactly what you're trying to but at the very least directly using the underlying net.TCPConn is going to be tricky. For one thing it might be net.UnixConn, and if it is a net.TCPConn then it might have a tls.Conn wrapping it.

But regardless, I think what you can do is to set a custom DialFunc on https://pkg.go.dev/github.com/jackc/pgx/[email protected]/pgconn#Config. You'd need to save the reference somewhere and map it back to the pgx.Conn that was ultimately created. A little messy, but it should be possible.

[mhkarimi1383]

Thanks I will check it out
but that copyBuffer is the same as io.Copy
I want to use that just like io.Copy

[mhkarimi1383]

I need this for my https://github.com/mhkarimi1383/pg_pro project

[hothanhloc68]

I know that this problem is not fully related to this project, but I need help with my problem

func GetRawConnection() (net.Conn, error) {
	conn, err := writePools[rand.Intn(len(writePools))].Acquire(context.Background())
	if err != nil {
		return nil, err
	}
	return conn.Conn().PgConn().Conn(), nil
}

and use it as a normal TCPConn but I'm getting following error

panic: interface conversion: net.Conn is *nbconn.NetConn, not *net.TCPConn

Also I cannot use nbconn.NetConn since it's in internal module also conn property is not public

here is my code that is code that uses GetRawConnection

func handleClient(cliConn *net.TCPConn) {
	defer cliConn.Close()

	serverConn, err := connection.GetRawConnection()
	if err != nil {
		log.Printf("Failed to connect to server: %s", err)
		return
	}
	defer serverConn.Close()
	fmt.Printf("Type of cliConn: %T\n", cliConn)
	fmt.Printf("Type of serverConn: %T\n", serverConn)
	// Proxy(serverConn.(*net.TCPConn), cliConn)
	Proxy(serverConn.(*net.TCPConn), cliConn)
}

func Proxy(srvConn, cliConn *net.TCPConn) {
	serverClosed := make(chan struct{}, 1)
	clientClosed := make(chan struct{}, 1)
	// backend := pgproto3.NewBackend(cliConn, cliConn)

	// startupMsg, err := backend.ReceiveStartupMessage()
	// if err != nil {
	// 	log.Fatal(err)
	// }
	// backend.SetAuthType(pgproto3.AuthTypeMD5Password)

	// switch startupMsg.(type) {
	// case *pgproto3.StartupMessage:
	//	_, err := cliConn.Write((&pgproto3.AuthenticationMD5Password{
	//		Salt: types.MD5AuthSalt,
	//	}).Encode(nil))
	//	if err != nil {
	//		log.Fatal(err)
	//	}
	//}

	go broker(srvConn, cliConn, clientClosed)
	go broker(cliConn, srvConn, serverClosed)

	var waitFor chan struct{}
	select {
	case <-clientClosed:
		srvConn.SetLinger(0)
		srvConn.CloseRead()
		waitFor = serverClosed
	case <-serverClosed:
		cliConn.CloseRead()
		waitFor = clientClosed
	}

	<-waitFor
}

func broker(dst, src net.Conn, srcClosed chan struct{}) {
	_, err := copyBuffer(dst, src, nil)
	if err != nil {
		log.Printf("Copy error: %s", err)
	}
	if err := src.Close(); err != nil {
		log.Printf("Close error: %s", err)
	}
	srcClosed <- struct{}{}
}

Thanks

[jackc]

nbconn.NetConn has been removed from pgx so this should no longer be relevant.