cmd/torrent-metainfo-pprint/main.go

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