100行你就可以做到类似nginx带自动更新的端口转发功能
总共就2个文件，一个main（总行数128行），一个配置文件
main：
里面的json解析和log可以忽略
package main
import (
"github.com/weimingjue/json"
utils2 "goProxy/utils"
"goService/utils"
"io/ioutil"
"net"
"net/http"
"net/http/httputil"
"net/url"
"os"
"strings"
"sync"
"time"
)
var (
projectDir, _ = os.Getwd()
fileName = projectDir + "/domain.config"
readFileTime int64 = 0 //读取文件的时间
fileChangedTime int64 = 0 //文件修改时间
domainData [][]string //[{***.gq,8080,http://127.0.0.1:8080/}]
duPeiZhiSuo sync.Mutex //读配置锁
)
// 获取反向代理域名
func getProxyUrl(reqDomain string) string {
checkFile()
for _, dms := range domainData {
if strings.Index(reqDomain, dms[0]) >= 0 {
return dms[2]
}
}
return domainData[0][2]
}
//读取配置文件
//域名:端口号，未知域名默认用第一个
func checkFile() {
nowTime := time.Now().Unix()
if nowTime-readFileTime < 300 {
return
}
//每5分钟判断文件是否修改
domainFile, _ := os.OpenFile(fileName, os.O_WRONLY|os.O_APPEND, 0)
info, _ := domainFile.Stat()
if info.ModTime().Unix() == fileChangedTime {
return
}
duPeiZhiSuo.Lock()
defer duPeiZhiSuo.Unlock()
domainFile, _ = os.OpenFile(fileName, os.O_WRONLY|os.O_APPEND, 0) //加锁再来一遍，防止重入
info, _ = domainFile.Stat()
changedTime := info.ModTime().Unix()
if changedTime == fileChangedTime {
return
}
//文件改变
//重置数据
readFileTime = nowTime
fileChangedTime = changedTime
domainData = [][]string{}
bytes, _ := ioutil.ReadFile(fileName)
split := strings.Split(string(bytes), "\n")
for _, domainInfo := range split {
dLen := len(domainInfo)
if dLen < 8 || dLen > 20 { //忽略错误信息
continue
}
domainItems := strings.Split(domainInfo, ":")
if len(domainItems) != 2 || len(domainItems[0]) < 3 || len(domainItems[1]) < 2 {
continue
}
if utils.EndWidth(domainItems[1], "/") {
domainItems = append(domainItems, "http://127.0.0.1:"+domainItems[1])
} else {
domainItems = append(domainItems, "http://127.0.0.1:"+domainItems[1]+"/")
}
domainData = append(domainData, domainItems)
}
domainSt, _ := json.Marshal(domainData)
utils2.MyLogProxyI("配置已修改：" + string(domainSt))
}
//获取主机名
func getHost(req *http.Request) string {
if req.Host != "" {
if hostPart, _, err := net.SplitHostPort(req.Host); err == nil {
return hostPart
}
return req.Host
}
return "localhost"
}
func handleRequestAndRedirect(res http.ResponseWriter, req *http.Request) {
host := getHost(req)
proxyUrl := getProxyUrl(host)
url2, _ := url.Parse(proxyUrl)
utils2.MyLogProxyI("请求域名：" + host + "，转到：" + proxyUrl)
// create the reverse proxy
proxy := httputil.NewSingleHostReverseProxy(url2)
// Update the headers to allow for SSL redirection
req.URL.Host = url2.Host
req.URL.Scheme = url2.Scheme
req.Header.Set("X-Forwarded-Host", req.Header.Get("Host"))
req.Host = url2.Host
// Note that ServeHttp is non blocking and uses a go routine under the hood
proxy.ServeHTTP(res, req)
}
func main() {
http.HandleFunc("/", handleRequestAndRedirect)
if err := http.ListenAndServe(":80", nil); err != nil {
utils.MyLogE("Proxy监听80端口错误：" + err.Error())
panic(err)
}
}domain.config：
***为自己的域名，":"后面是需要转发的端口，不用写http://，任何地方都不能有空格
wang.gq:8080
***.aa:8081/