Golang: how to read response body of ReverseProxy?

Question

package main

import (
    \"net/http\"
    \"net/http/httputil\"
    \"net/url\"
)

func main() {
    target := &url.URL{Scheme: \"http\", Host: \"www.google.com\"}         


        

Answer 1

I don't know best solution. But you can do something like this:

package main

import (
    "fmt"
    "net/http"
    "net/http/httputil"
    "net/url"
)

func main() {
    target := &url.URL{Scheme: "http", Host: "www.google.com"}
    proxy := httputil.NewSingleHostReverseProxy(target)

    http.Handle("/google", CustomHandler(proxy))
    http.ListenAndServe(":8099", nil)
}

func CustomHandler(h http.Handler) http.HandlerFunc {
    return func(res http.ResponseWriter, req *http.Request) {
        h.ServeHTTP(NewCustomWriter(res), req)
    }
}

type customWriter struct {
    http.ResponseWriter
}

func NewCustomWriter(w http.ResponseWriter) *customWriter {
    return &customWriter{w}
}

func (c *customWriter) Header() http.Header {
    return c.ResponseWriter.Header()
}

func (c *customWriter) Write(data []byte) (int, error) {
    fmt.Println(string(data)) //get response here
    return c.ResponseWriter.Write(data)
}

func (c *customWriter) WriteHeader(i int) {
    c.ResponseWriter.WriteHeader(i)
}