main.go

package main

import (
  "bufio"
  "fmt"
  "log"
  "net"
  "os"
  "strings"
)

func main() {
  scanner := bufio.NewScanner(os.Stdin)
  fmt.Printf("domain, hasMx, hasSPF, sprRecord, hasDMARC, dmarcRecord\n")

  for scanner.Scan() {
    checkDomain(scanner.Text())
  }

  if err := scanner.Err(); err!= nil {
    fmt.Printf("Error: Not able to read your input: %v\n", err)
  }
}

func checkDomain(domain string) {
  var hasMx, hasSPF, hasDMRK bool
  var spfRecord, dmarcRecord string
  mxRecords, err := net.LookupMX(domain)
  if err != nil {
    log.Printf("Error: %v\n", err)
  }

  if len(mxRecords) > 0 {
    hasMx =true;
  }
  txRecords, err := net.LookupTXT(domain)

  if err != nil {
    log.Printf("Error: %v\n", err)
  }


  for _, record := range txRecords {
    if strings.HasPrefix(record, "v=spf1") {
      hasSPF = true;
      spfRecord = record;
      break;
    }
  }

  dmarcRecords , err := net.LookupTXT("_dmarc."+ domain)
  if err != nil {
    log.Printf("Error: %v\n", err)
  }

  for _, record := range dmarcRecords {
    if strings.HasPrefix(record, "v=DMARC1") {
      hasDMRK = true
      dmarcRecord = record;
      break;
    }
  }

  fmt.Printf("%v %v %v %v %v %v", domain, hasMx, hasSPF, spfRecord, hasDMRK, dmarcRecord);

}