目录

客户端代码

// socket_stick/client2/main.gofunc main() {conn, err := net.Dial("tcp", "127.0.0.1:30000")if err != nil {fmt.Println("dial failed, err", err)return}defer conn.Close()for i := 0; i < 20; i++ {msg := `Hello, Hello. How are you?`data, err := proto.Encode(msg)if err != nil {fmt.Println("encode msg failed, err:", err)return}conn.Write(data)}}

服务端代码

func process(conn net.Conn) {defer conn.Close()reader := bufio.NewReader(conn)for {msg, err := proto.Decode(reader)if err == io.EOF {return}if err != nil {fmt.Println("decode msg failed, err:", err)return}fmt.Println("收到client发来的数据：", msg)}}func main() {listen, err := net.Listen("tcp", "127.0.0.1:30000")if err != nil {fmt.Println("listen failed, err:", err)return}defer listen.Close()for {conn, err := listen.Accept()if err != nil {fmt.Println("accept failed, err:", err)continue}go process(conn)}}

封包协议

封包：封包就是给一段数据加上包头，这样一来数据包就分为包头和包体两部分内容了(过滤非法包时封包会加入”包尾”内容)。包头部分的长度是固定的，并且它存储了包体的长度，根据包头长度固定以及包头中含有包体长度的变量就能正确的拆分出一个完整的数据包。

数据包的前4个字节为包头，里面存储的是发送的数据的长度。

package protoimport ("bufio""bytes""encoding/binary")// Encode 将消息编码func Encode(message string) ([]byte, error) {// 读取消息的长度，转换成int32类型（占4个字节）var length = int32(len(message))var pkg = new(bytes.Buffer)// 写入消息头err := binary.Write(pkg, binary.LittleEndian, length)if err != nil {return nil, err}// 写入消息实体err = binary.Write(pkg, binary.LittleEndian, []byte(message))if err != nil {return nil, err}return pkg.Bytes(), nil}// Decode 解码消息func Decode(reader *bufio.Reader) (string, error) {// 读取消息的长度lengthByte, _ := reader.Peek(4) // 读取前4个字节的数据lengthBuff := bytes.NewBuffer(lengthByte)var length int32err := binary.Read(lengthBuff, binary.LittleEndian, &length)if err != nil {return "", err}// Buffered返回缓冲中现有的可读取的字节数。if int32(reader.Buffered()) < length+4 {return "", err}// 读取真正的消息数据pack := make([]byte, int(4+length))_, err = reader.Read(pack)if err != nil {return "", err}return string(pack[4:]), nil}