tcp.go

package main

import (
	"github.com/bitly/nsq/nsq"
	"github.com/bitly/nsq/util"
	"io"
	"log"
	"net"
)

type TcpProtocol struct {
	util.TcpHandler
	protocols map[string]nsq.Protocol
}

func (p *TcpProtocol) Handle(clientConn net.Conn) {
	log.Printf("TCP: new client(%s)", clientConn.RemoteAddr())

	// The client should initialize itself by sending a 4 byte sequence indicating
	// the version of the protocol that it intends to communicate, this will allow us
	// to gracefully upgrade the protocol away from text/line oriented to whatever...
	buf := make([]byte, 4)
	_, err := io.ReadFull(clientConn, buf)
	if err != nil {
		log.Printf("ERROR: failed to read protocol version - %s", err.Error())
		return
	}
	protocolMagic := string(buf)

	log.Printf("CLIENT(%s): desired protocol magic '%s'", clientConn.RemoteAddr(), protocolMagic)

	prot, ok := p.protocols[protocolMagic]
	if !ok {
		nsq.SendFramedResponse(clientConn, nsq.FrameTypeError, []byte("E_BAD_PROTOCOL"))
		clientConn.Close()
		log.Printf("ERROR: client(%s) bad protocol magic '%s'", clientConn.RemoteAddr(), protocolMagic)
		return
	}

	err = prot.IOLoop(clientConn)
	if err != nil {
		log.Printf("ERROR: client(%s) - %s", clientConn.RemoteAddr(), err.Error())
		return
	}
}