torrentfile

Documentation

Overview

Package torrentfile parses torrent files or magnet links.

Index

• type File
• type TorrentFile
  • func New(source string) (TorrentFile, error)
  • func (t *TorrentFile) AppendMetadata(metadata []byte) error

Types

type File

type File struct {
	Length   int    // length in bytes
	FullPath string // download path
	SHA1Hash string // optional for final validation
	MD5Hash  string // optional for final validation
}

File contains metadata about the final downloaded files, namely their path and file length.

type TorrentFile

type TorrentFile struct {
	TrackerURLs []string   // tracker URLs (from announce-list, announce or magnet link tr)
	InfoHash    [20]byte   // SHA-1 hash of the entire info field, uniquely identifies the torrent
	PieceHashes [][20]byte // SHA-1 hashes of each file piece
	PieceLength int        // number of bytes per piece
	Files       []File     // in the 1 file case, this will only have one element
	TotalLength int        // calculated as the sum of all files
	DisplayName string     // human readable display name (.torrent filename or magnet link dn)
}

TorrentFile represents the contents of a .torrent file, reformatted for ease of use in the download process.

The InfoHash is generated via SHA-1 from the entire Info field of the file.

The 20-byte SHA1 hashes are formatted into a slice of 20-byte arrays for easy comparison with pieces downloaded from a peer.

func New

func New(source string) (TorrentFile, error)

New returns a new TorrentFile.

If the source is a .torrent file, it will be ready for use.

If the source is a magnet link, metadata will need to be acquired from peers already in the swarm, then added using TorrentFile.AppendMetadata()

func (*TorrentFile) AppendMetadata

func (t *TorrentFile) AppendMetadata(metadata []byte) error

AppendMetadata adds the metadata (aka the info dictionary of a torrent file). It must be called after torrentfile.New() is invoked with a magnet link source with the metadata acquired from a peer in the swarm.