add wireformat question creation from string or stdin

cmd/wireformat/wireformat.go

@@ -1,18 +1,25 @@
 package main
 
 import (
+	"encoding/binary"
 	"errors"
 	"flag"
 	"io/ioutil"
 	"log"
+	"os"
+	"strings"
 
 	"github.com/miekg/dns"
 )
 
 func main() {
 	file := flag.String("f", "", "file path to read hexa decimal wireformat data")
+	domainToResolve := flag.String("s", "-", "Server adress to resolve")
 	flag.Parse()
 
+	// remove timestamp prefix from log out
+	log.SetFlags(0)
+
 	var body []byte
 	var err error
 	if *file != "" {
@@ -31,6 +38,28 @@ func main() {
 		}
 
 		log.Println(msg)
+	} else if *domainToResolve != "" {
+		if *domainToResolve == "-" {
+			readDomainToResolve, err := ioutil.ReadFile("/dev/stdin")
+			if err != nil {
+				log.Fatalln(err)
+			}
+			*domainToResolve = strings.TrimSuffix(string(readDomainToResolve), "\n")
+		}
+		msg := &dns.Msg{
+			Question: []dns.Question{
+				dns.Question{
+					dns.Fqdn(*domainToResolve),
+					dns.TypeANY,
+					dns.ClassINET,
+				},
+			},
+		}
+		b, err := msg.Pack()
+		if err != nil {
+			log.Fatalln(err)
+		}
+		binary.Write(os.Stdout, binary.LittleEndian, b)
 	} else {
 		log.Println(errors.New("Too few argument pass"))
 		flag.Usage()

readme.md

@@ -16,3 +16,8 @@ With post resolution
 
 `curl -s -H accept: application/dns-message https://cloudflare-dns.com/dns-query?dns=q80BAAABAAAAAAAAA3d3dwdleGFtcGxlA2NvbQAAAQAB | ./bin/wireformat -f -`
 
+Wireformat encode and decode
+
+`./bin/wireformat -s 'www.example.com' | ./bin/wireformat -f -`
+
+`echo 'www.example.com' | ./bin/wireformat | ./bin/wireformat -f -`