cmd/torrent-metainfo-pprint/main.go

   1 package main
   2
   3 import (
   4         "bufio"
   5         "encoding/hex"
   6         "encoding/json"
   7         "fmt"
   8         "io"
   9         "log"
  10         "os"
  11
  12         "github.com/anacrolix/envpprof"
  13         "github.com/anacrolix/tagflag"
  14         "github.com/bradfitz/iter"
  15
  16         "github.com/anacrolix/torrent/metainfo"
  17 )
  18
  19 var flags struct {
  20         JustName    bool
  21         PieceHashes bool
  22         Files       bool
  23         tagflag.StartPos
  24 }
  25
  26 func processReader(r io.Reader) error {
  27         metainfo, err := metainfo.Load(r)
  28         if err != nil {
  29                 return err
  30         }
  31         info, err := metainfo.UnmarshalInfo()
  32         if err != nil {
  33                 return fmt.Errorf("error unmarshalling info: %s", err)
  34         }
  35         if flags.JustName {
  36                 fmt.Printf("%s\n", info.Name)
  37                 return nil
  38         }
  39         d := map[string]interface{}{
  40                 "Name":         info.Name,
  41                 "NumPieces":    info.NumPieces(),
  42                 "PieceLength":  info.PieceLength,
  43                 "InfoHash":     metainfo.HashInfoBytes().HexString(),
  44                 "NumFiles":     len(info.UpvertedFiles()),
  45                 "TotalLength":  info.TotalLength(),
  46                 "Announce":     metainfo.Announce,
  47                 "AnnounceList": metainfo.AnnounceList,
  48                 "UrlList":      metainfo.UrlList,
  49         }
  50         if flags.Files {
  51                 d["Files"] = info.UpvertedFiles()
  52         }
  53         if flags.PieceHashes {
  54                 d["PieceHashes"] = func() (ret []string) {
  55                         for i := range iter.N(info.NumPieces()) {
  56                                 ret = append(ret, hex.EncodeToString(info.Pieces[i*20:(i+1)*20]))
  57                         }
  58                         return
  59                 }()
  60         }
  61         b, _ := json.MarshalIndent(d, "", "  ")
  62         _, err = os.Stdout.Write(b)
  63         return err
  64 }
  65
  66 func main() {
  67         defer envpprof.Stop()
  68         tagflag.Parse(&flags)
  69         err := processReader(bufio.NewReader(os.Stdin))
  70         if err != nil {
  71                 log.Fatal(err)
  72         }
  73         if !flags.JustName {
  74                 os.Stdout.WriteString("\n")
  75         }
  76 }