如何使用go从端口80无缝地管道传输/转发到端口XXXX？

I have a bunch of websites running on one server (single IP) and they all run on high ports so I don't need root to run them.

When someone visits from one web address, lets say, http://address001.com/, I want to seamlessly pipe the data from port 4444 to the person who made this request, and if someone visits http://address002.com/ I want to pipe the data from port 5555.

How would I do this in Go?

So far I have a handler function that looks like this:

func home(w http.ResponseWriter, r *http.Request) {                      
  if strings.Contains(r.Host, "address001") {                    
    // ???
  }                                                                      
}  

you can use httputil's ReverseProxy

here's an example code

package main

import (
    "log"
    "net/http"
    "net/http/httputil"
)

func main() {
    director := func(req *http.Request) {
        switch req.Host {
        case "address001.com":
            req.URL.Host = "localhost:4444"
            req.URL.Scheme = "http"
        case "address002.com":
            req.URL.Host = "localhost:5555"
            req.URL.Scheme = "http"
        default:
            log.Println("error")
        }
    }
    proxy := &httputil.ReverseProxy{Director: director}
    log.Fatalln(http.ListenAndServe(":8080", proxy))
}