How to read multiple lines in Go without breaking connections?

Question

go

There is this code:

func main() {
  ln,  _ := net.Listen("tcp", ":6556")
  defer ln.Close()
  for {
    con, _ := ln.Accept()
    go handleServer(conn)
  }
}

func handleServer(conn net.Conn) {
  buf := make([]byte, 0, 4096)
  n, _ := conn.Read(buf)
  log.Printf("Received line length: %d\n", n)
  conn.Write([]byte("Message received.\n"))
  conn.Close()
}

Now, if conn.Close() is removed in the handleServer () function , then the connection does not break, but it does not read anything more than the first line, however, as I thought it should have read each line.
How can I read all the lines one by one?

Answer 1

Here is an example code. Here we read incoming data line by line and send "Message received" after each line is read. Reading continues until the client closes the connection.

package main

import (
  "bufio"
  "log"
  "net"
)

func main() {
  ln, _ := net.Listen("tcp", ":6556")
  defer ln.Close()
  for {
    conn, _ := ln.Accept()
    go handleServer(conn)
  }
}

func handleServer(conn net.Conn) {
  reader := bufio.NewReader(conn)
  defer conn.Close()

  for {
    line, err := reader.ReadString('\n')
    if err != nil {
      return
    }
    conn.Write([]byte("Message received.\n"))
    log.Printf("Received line length: %d\n", len(line))
  }
}