以下是从golang并发编程实战2中摘抄过来的代码片段,主要是实现一个简单的tcp socket通讯(客户端发送一个数字,服务端计算该数字的立方根然后返回),写的不错,用到了go的并发以及看下郝林大神是如何处理socket通讯的。具体代码记录如下,多看多学习多共勉:
package main
import (
"net"
"strings"
"fmt"
"time"
"io"
"bytes"
"strconv"
"math"
"math/rand"
"sync"
)
const (
SERVER_NETWORK = "tcp"
SERVER_ADDRESS = "127.0.0.1:8085"
DELIMITER = '\t'
)
var wg sync.WaitGroup
func main() {
wg.Add(2)
go serverGo()
time.Sleep(500 * time.Millisecond)
go clientGo(1)
wg.Wait()
}
func serverGo() {
defer wg.Done()
listener, err := net.Listen(SERVER_NETWORK, SERVER_ADDRESS)
if err != nil {
printServerLog("Listen Error: %s", err)
return
}
defer listener.Close()
printServerLog("Got listener for the server.(local address: %s)", listener.Addr())
for {
conn, err := listener.Accept()
if err != nil {
printServerLog("Accept Error: %s", err)
}
printServerLog("Established a connection with a client application,(remote address: %s)", conn.RemoteAddr())
go handleConn(conn)
}
}
func printLog(role string, sn int, format string, args ...interface{}) {
if !strings.HasSuffix(format, "\n") {
format += "\n"
}
fmt.Printf("%s[%d]: %s", role, sn, fmt.Sprintf(format, args...))
}
func printServerLog(format string, args ...interface{}) {
printLog("Server", 0, format, args...)
}
func printClientLog(sn int, format string, args ...interface{}) {
printLog("Cient", sn, format, args...)
}
func handleConn(conn net.Conn) {
defer conn.Close()
for {
conn.SetDeadline(time.Now().Add(10 * time.Second)) // set read timeline 10s
strReq, err := read(conn)
if err != nil {
if err == io.EOF {
printServerLog("The connection is closed by another side.")
} else {
printServerLog("Read Error: %s", err)
}
break
}
printServerLog("Received request: %s", strReq)
intReq, err := strToInt32(strReq)
if err != nil {
n, err := write(conn, err.Error())
printServerLog("Sent error message (written %d bytes): %s", n, err)
continue
}
floatResp := cbrt(intReq)
respMsg := fmt.Sprintf("The cube root of %d is %f.", intReq, floatResp)
n, err := write(conn, respMsg)
if err != nil {
printServerLog("Sent response message (written %d bytes: %s).", n, respMsg)
}
}
}
func read(conn net.Conn) (string, error){
readBytes := make([]byte, 1)
var buffer bytes.Buffer
for {
_, err := conn.Read(readBytes)
if err != nil {
return "", err
}
readByte := readBytes[0]
if readByte == DELIMITER {
break
}
buffer.WriteByte(readByte)
}
return buffer.String(), nil
}
func strToInt32(str string) (int32, error){
i32, err := strconv.ParseInt(str, 10 ,32)
return int32(i32), err
}
func write(conn net.Conn, content string) (int, error) {
var buffer bytes.Buffer
buffer.WriteString(content)
buffer.WriteByte(DELIMITER)
return conn.Write(buffer.Bytes())
}
func cbrt(intReq int32) float64 {
return math.Cbrt(float64(intReq))
}
func clientGo(id int) {
defer wg.Done()
conn, err := net.DialTimeout(SERVER_NETWORK, SERVER_ADDRESS, 2 * time.Second)
if err != nil {
printClientLog(id, "Dial Error: %s", err)
return
}
defer conn.Close()
printClientLog(id, "Connected to server.(remote address: %s,local address: %s)", conn.RemoteAddr(), conn.LocalAddr())
time.Sleep(200 * time.Millisecond)
requestNumber := 5
conn.SetDeadline(time.Now().Add(5 * time.Millisecond))
for i := 0; i< requestNumber; i++ {
req := rand.Int31()
n, err := write(conn, fmt.Sprintf("%d", req))
if err != nil {
printClientLog(id, "Write Error: %s", err)
continue
}
printClientLog(id, "Sent request (written %d bytes)", n)
}
for j := 0; j< requestNumber; j++ {
strResp, err := read(conn)
if err != nil {
if err == io.EOF {
printClientLog(id, "The connection is closed by another side.")
}else{
printClientLog(id, "Read Error: %s", err)
}
break
}
printClientLog(id, "Received response: %s", strResp)
}
}
执行效果: