Just because you can, doesn't mean you should.
This is a toy bittorrent client in C#. I am using this to learn. You shouldn't use it in the wild or really even use it as a reference.
Thanks to Jesse Li's bittorrent-in-go post for convincing me that this was worth a shot. I was fascinated by bittorrent when I was first learning computer science; I feel something of a return to those days to finally attempt to implement it myself.
- Jesse Li's Bittorrent post (broad strokes, glosses over a lot)
- sujanan/tnt for a separate but readable implementation
- The actual bittorrent specification
- Wikipedia:Torrent_file
A very basic tracker is implemented in Perl. I use it to point my torrents to localhost bittorrent clients so I don't embarrass myself fumbling around on a real swarm.
It's read-only, provide your local clients via comma separated ports in env.
All peers are 127.0.0.1.
# install dependencies
$ cpanm Plack Bencode
# provide ports via env, comma separated
$ WESTORRENT_LOCAL_PEERS=33854,51413 plackup -r &
Watching app.psgi for file updates.
HTTP::Server::PSGI: Accepting connections at http://0:5000/
$ curl localhost:5000 | xxd
00000000: 6438 3a69 6e74 6572 7661 6c69 3330 6535 d8:intervali30e5
00000010: 3a70 6565 7273 3132 3a7f 0000 0184 3e7f :peers12:.....>.
00000020: 0000 01c8 d565 .....e
- parse torrent file
- get peers via tracker announce
- connect to peer
- download piece from peer
- save piece in file storage
- connect to peers from tracker
- merge peer list after re-announce
- multiple connections
- handle timeouts from connections and piece dl
- fix terrible performance
- threads??
- recursive bencode parser for better torrent support
- multi-file torrents
- restore progress after restart