1. package main
    3. import (
    4.     "flag"
    5.     "github.com/rs/zerolog"
    6.     "net"
    7.     "os"
    8. )
    10. var logger = zerolog.New(os.Stdout).With().Timestamp().Logger()
    12. func main() {
    13.     help := flag.Bool("help", false, "print usage")
    14.     bind := flag.String("bind", "127.0.0.1:6000", "The address to bind to")
    15.     backend := flag.String("backend", "", "The backend server address")
    16.     flag.Parse()
    18.     logger.Level(zerolog.DebugLevel)
    20.     if *help {
    21.         flag.Usage()
    22.         return
    23.     }
    25.     if *backend == "" {
    26.         flag.Usage()
    27.         return
    28.     }
    30.     if *bind == "" {
    31.         //use default bind
    32.         logger.Info().Str("bind", *bind).Msg("use default bind")
    33.     }
    35.     success, err := RunProxy(*bind, *backend)
    36.     if !success {
    37.         logger.Error().Err(err).Send()
    38.         os.Exit(1)
    39.     }
    40. }
    42. func RunProxy(bind, backend string) (bool, error) {
    43.     listener, err := net.Listen("tcp", bind)
    44.     if err != nil {
    45.         return false, err
    46.     }
    47.     defer listener.Close()
    48.     logger.Info().Str("bind", bind).Str("backend", backend).Msg("tcp-proxy started.")
    49.     for {
    50.         conn, err := listener.Accept()
    51.         if err != nil {
    52.             logger.Error().Err(err).Send()
    53.         } else {
    54.             go ConnectionHandler(conn, backend)
    55.         }
    56.     }
    57. }
    59. func ConnectionHandler(conn net.Conn, backend string) {
    60.     logger.Info().Str("conn", conn.RemoteAddr().String()).Msg("client connected.")
    61.     target, err := net.Dial("tcp", backend)
    62.     defer conn.Close()
    63.     if err != nil {
    64.         logger.Error().Err(err).Send()
    65.     } else {
    66.         defer target.Close()
    67.         logger.Info().Str("conn", conn.RemoteAddr().String()).Str("backend", target.LocalAddr().String()).Msg("backend connected.")
    68.         closed := make(chan bool, 2)
    69.         go Proxy(conn, target, closed)
    70.         go Proxy(target, conn, closed)
    71.         <-closed
    72.         logger.Info().Str("conn", conn.RemoteAddr().String()).Msg("Connection closed.")
    73.     }
    74. }
    76. func Proxy(from net.Conn, to net.Conn, closed chan bool) {
    77.     buffer := make([]byte, 4096)
    78.     for {
    79.         n1, err := from.Read(buffer)
    80.         if err != nil {
    81.             closed <- true
    82.             return
    83.         }
    84.         n2, err := to.Write(buffer[:n1])
    85.         logger.Debug().Str("from", from.RemoteAddr().String()).Int("recv", n1).Str("to", to.RemoteAddr().String()).Int("send", n2).Send()
    86.         if err != nil {
    87.             closed <- true
    88.             return
    89.         }
    90.     }
    91. }

    使用方法 ./proxy —bind 0.0.0.0:6379 —backend 10.0.1.15:6379