A proxy server support Http And Https

HttpProxy.go

package main

import (
	"fmt"
	"io"
	"log"
	"net"
	"net/url"
	"strings"
)

/**
* 代理服务，启动一个代理服务，支持https和http服务.
* @author fukun 2019-02-19
**/
func main() {
	fmt.Println("hello, proxy")

	ln, err := net.Listen("tcp4", ":8080")
	if err != nil {
		log.Fatalln(err)
	}
	for {
		conn, err := ln.Accept()
		if err != nil {
			log.Fatalln(err)
		}
		go handle(conn)
	}

}

func handle(pconn net.Conn) {
	var b [2048]byte
	n, err := pconn.Read(b[:])
	defer pconn.Close()
	fmt.Println(n, string(b[:]))
	// getRemoteAddr
	headerstrs := strings.Split(string(b[:]), "\r\n")
	var method string
	var turl string
	var version string
	n, err = fmt.Sscanf(headerstrs[0], "%s %s %s", &method, &turl, &version)
	// fmt.Println(method, turl, version)
	parseURL, err := url.Parse(turl)
	fmt.Println(parseURL.Host, parseURL.Scheme, err)
	var targetHost string
	if method == "CONNECT" {
		targetHost = turl
	} else {
		targetPort := ""
		if parseURL.Port() == "" {
			targetPort = "80"
		}
		targetHost = fmt.Sprintf("%s:%s", parseURL.Host, targetPort)
	}
	fmt.Println("dial remote addr: ", targetHost)
	conn, err := net.Dial("tcp4", targetHost)
	if method == "CONNECT" {
		pconn.Write([]byte("HTTP/1.1 200 Connection established\r\n\r\n"))
	} else {
		conn.Write(b[:])
	}
	if err != nil {
		log.Fatalln(err)
	}
	stop := make(chan struct{}, 1)
	go func() {
		_, err := io.Copy(pconn, conn)
		if err != nil {
			log.Fatalln("copy pconn to conn", err)
		}
		stop <- struct{}{}
	}()
	go func() {
		_, err := io.Copy(conn, pconn)
		if err != nil {
			log.Fatalln(err)
		}
		stop <- struct{}{}
	}()
	<-stop
	<-stop
	conn.Close()
}