DNS over HTTP/2

main.go

package main

import (
	"bytes"
	"fmt"
	"io/ioutil"
	"log"
	"net/http"

	"github.com/miekg/dns"
)

func main() {
	client := &http.Client{}
	m := new(dns.Msg)
	m.SetQuestion("miek.nl.", dns.TypeDNSKEY)
	m.SetEdns0(4096, true)
	out, err := m.Pack()
	if err != nil {
		log.Fatal(err)
	}
	req, err := http.NewRequest("POST", "https://dns.cloudflare.com:443", bytes.NewReader(out))
	if err != nil {
		log.Fatal(err)
	}
	req.Header.Set("content-type", "application/dns-udpwireformat")
	req.Header.Set("cache-control", "max-age=128")

	resp, err := client.Do(req)
	if err != nil {
		log.Fatal(err)
	}

	buf, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		log.Fatal(err)
	}

	rm := new(dns.Msg)
	if err := rm.Unpack(buf); err != nil {
		log.Fatal(err)
	}
	fmt.Printf("%s\n", rm)
}