pythonTorrentDHT

A Python implementation of the BitTorrent Distributed Hash Table, extending nitmir/btdht with additional BEP support.

Overview

pythonTorrentDHT provides a full Python implementation of the BitTorrent mainline DHT. It is a natural evolution of nitmir/btdht, modernised for Python 3.10+ (pure Python, no Cython) and extended with additional BitTorrent Enhancement Proposals:

BEP	Description
BEP 5	BitTorrent DHT Protocol — core routing table, get_peers, announce_peer
BEP 9	Extension for Peers to Send Metadata Files — fetch .torrent info-dicts without a tracker
BEP 10	Extension Protocol — peer capability negotiation (required by BEP 9)
BEP 51	DHT Infohash Indexing — sample_infohashes for crawling the DHT

Requirements

• Python 3.10+
• datrie
• netaddr

No C compiler required.

Installation

pip install pythontorrentdht

Or from source:

git clone https://github.com/Sprooty/pythonTorrentDHT
cd pythonTorrentDHT
pip install -e .

Usage

Find peers for a torrent

import btpydht
import binascii

dht = btpydht.DHT()
dht.start()  # allow ~15s to bootstrap

peers = dht.get_peers(binascii.a2b_hex("0403fb4728bd788fbcb67e87d6feb241ef38c75a"))
print(peers)
# [('81.171.107.75', 17744), ('94.242.250.86', 3813), ...]

dht.stop()

Fetch torrent metadata (BEP 9/10)

Retrieve the info-dict directly from a peer without a .torrent file:

from btpydht.metadata import get_metadata

info_hash = binascii.a2b_hex("0403fb4728bd788fbcb67e87d6feb241ef38c75a")
peers = dht.get_peers(info_hash)

metadata = get_metadata(info_hash, peers[0])
print(metadata[b"name"])

Sample infohashes from the DHT (BEP 51)

Walk the DHT and collect infohashes being announced:

class CrawlerDHT(btpydht.DHT_BASE):
    def on_sample_infohashes_response(self, response):
        for ih in response.get(b"samples", []):
            print(ih.hex())

dht = CrawlerDHT()
dht.start()

Announce a torrent

info_hash = binascii.a2b_hex("0403fb4728bd788fbcb67e87d6feb241ef38c75a")
dht.announce_peer(info_hash, port=6881)

Extend with custom message handlers

Subclass btpydht.DHT_BASE and override on_<msg>_query / on_<msg>_response:

class MyDHT(btpydht.DHT_BASE):
    def on_get_peers_query(self, query):
        print(f"Peer request for: {query[b'info_hash'].hex()}")

dht = MyDHT()
dht.register_message(b"get_peers")
dht.start()

Save and restore routing table state

dht.save("routing_table.dat")
# later...
dht.load("routing_table.dat")

Development

pip install -r requirements-dev.txt
make test

Or run pytest directly:

python -m pytest tests/ -v

License

GPLv3 — see LICENSE for details.

Credits

Originally created by Valentin Samir.