p2p/public_ip.go

   1 package p2p
   2
   3 import (
   4         "io/ioutil"
   5         "net"
   6         "net/http"
   7         "strings"
   8         "time"
   9 )
  10
  11 var ipCheckServices = []string{
  12         "http://members.3322.org/dyndns/getip",
  13         "http://ifconfig.me/",
  14         "http://icanhazip.com/",
  15         "http://ifconfig.io/ip",
  16         "http://ident.me/",
  17         "http://whatismyip.akamai.com/",
  18         "http://myip.dnsomatic.com/",
  19         "http://diagnostic.opendns.com/myip",
  20         "http://myexternalip.com/raw",
  21 }
  22
  23 type IpResult struct {
  24         Success bool
  25         Ip      string
  26 }
  27
  28 var timeout = time.Duration(5)
  29
  30 func GetIP() *IpResult {
  31         resultCh := make(chan *IpResult, 1)
  32         for _, s := range ipCheckServices {
  33                 go ipAddress(s, resultCh)
  34         }
  35
  36         for {
  37                 select {
  38                 case result := <-resultCh:
  39                         return result
  40                 case <-time.After(time.Second * timeout):
  41                         return &IpResult{false, ""}
  42                 }
  43         }
  44 }
  45
  46 func ipAddress(service string, done chan<- *IpResult) {
  47         client := http.Client{Timeout: time.Duration(timeout * time.Second)}
  48         resp, err := client.Get(service)
  49         if err != nil {
  50                 return
  51         }
  52
  53         defer resp.Body.Close()
  54         data, err := ioutil.ReadAll(resp.Body)
  55         if err != nil {
  56                 return
  57         }
  58
  59         address := strings.TrimSpace(string(data))
  60         if net.ParseIP(address) != nil {
  61                 select {
  62                 case done <- &IpResult{true, address}:
  63                         return
  64                 default:
  65                         return
  66                 }
  67         }
  68 }