rqbit - bittorrent client in Rust

rqbit is a bittorrent client written in Rust. Has HTTP API and Web UI, and can be used as a library.

Also has a desktop app built with Tauri.

Usage quick start

Optional - start the server

Assuming you are downloading to ~/Downloads.

rqbit server start ~/Downloads

Download torrents

Assuming you are downloading to ~/Downloads. If the server is already started, -o ~/Downloads can be omitted.

rqbit download -o ~/Downloads 'magnet:?....' [https?://url/to/.torrent] [/path/to/local/file.torrent]

Web UI

Access with http://localhost:3030/web/. It looks similar to Desktop app, see screenshot below.

Desktop app

The desktop app is a thin wrapper on top of the Web UI frontend.

Download it in Releases for OSX and Windows. For Linux, build manually with

cargo tauri build

Performance

Anecdotally from a few reports, rqbit is faster than other clients they've tried, at least with their default settings.

Memory usage for the server is usually within a few tens of megabytes, which makes it great for e.g. RaspberryPI.

CPU is spent mostly on SHA1 checksumming.

Installation

There are pre-built binaries in Releases. If someone wants to put rqbit into e.g. homebrew, PRs welcome :)

If you have rust toolchain installed, this should work:

cargo install rqbit

Build

Just a regular Rust binary build process.

cargo build --release

Useful options

-v

Increase verbosity. Possible values: trace, debug, info, warn, error.

--list

Will print the contents of the torrent file or the magnet link.

--overwrite

If you want to resume downloading a file that already exists, you'll need to add this option.

--peer-connect-timeout=10s

This will increase the default peer connect timeout. The default one is 2 seconds, and it's sometimes not enough.

-r / --filename-re

Use a regex here to select files by their names.

Features and missing features

Some supported features

• Sequential downloading (the default and only option)
• Resume downloading file(s) if they already exist on disk
• Selective downloading using a regular expression for filename
• DHT support. Allows magnet links to work, and makes more peers available.
• HTTP API
• Pausing / unpausing / deleting (with files or not) APIs
• Stateful server
• Web UI

Bugs, missing features and other caveats

PRs are very welcome.

• Only supports BitTorrent V1 over TCP
• As this was created for personal needs, and for educational purposes, documentation, commit message quality etc. leave a lot to be desired.

HTTP API

By default it listens on http://127.0.0.1:3030.

curl -s 'http://127.0.0.1:3030/'

{
    "apis": {
        "GET /": "list all available APIs",
        "GET /dht/stats": "DHT stats",
        "GET /dht/table": "DHT routing table",
        "GET /torrents": "List torrents (default torrent is 0)",
        "GET /torrents/{index}": "Torrent details",
        "GET /torrents/{index}/haves": "The bitfield of have pieces",
        "GET /torrents/{index}/peer_stats": "Per peer stats",
        "GET /torrents/{index}/stats/v1": "Torrent stats",
        "GET /web/": "Web UI",
        "POST /rust_log": "Set RUST_LOG to this post launch (for debugging)",
        "POST /torrents": "Add a torrent here. magnet: or http:// or a local file.",
        "POST /torrents/{index}/delete": "Forget about the torrent, remove the files",
        "POST /torrents/{index}/forget": "Forget about the torrent, keep the files",
        "POST /torrents/{index}/pause": "Pause torrent",
        "POST /torrents/{index}/start": "Resume torrent",
        "POST /torrents/{index}/update_only_files": "Change the selection of files to download. You need to POST json of the following form {"only_files": [0, 1, 2]}"
    },
    "server": "rqbit"
}

Add torrent through HTTP API

curl -d 'magnet:?...' http://127.0.0.1:3030/torrents

OR

curl -d 'http://.../file.torrent' http://127.0.0.1:3030/torrents

OR

curl --data-binary @/tmp/xubuntu-23.04-minimal-amd64.iso.torrent http://127.0.0.1:3030/torrents

Supported query parameters, all optional:

• overwrite=true|false
• only_files_regex - the regular expression string to match filenames
• output_folder - the folder to download to. If not specified, defaults to the one that rqbit server started with
• list_only=true|false - if you want to just list the files in the torrent instead of downloading

Code organization

• crates/rqbit - main binary
• crates/librqbit - main library
• crates/librqbit-core - torrent utils
• crates/bencode - bencode serializing/deserializing
• crates/buffers - wrappers around binary buffers
• crates/clone_to_owned - a trait to make something owned
• crates/sha1w - wrappers around sha1 libraries
• crates/peer_binary_protocol - the protocol to talk to peers
• crates/dht - Distributed Hash Table implementation
• desktop - desktop app built with Tauri

Motivation

First of all, I love Rust. The project was created purely for the fun of the process of writing code in Rust.

I was not satisfied with my regular bittorrent client, and was wondering how much work would it be to create a new one from scratch, and it got where it is, starting from bencode protocol implemenation, then peer protocol, etc, etc.