MIM- A Torrent Client

Overview

MIM is a command line torrent application that lets you download torrent files from the internet. As opposed to the general notion that torrents are used for piracy, a lot of stuff on the internet is downloadable through torrents (peer 2 peer networks). For instance, many popular Linux distros are easily downloadable through torrent clients at very fast speeds due to the peer-2-peer network capabilities. We aim to implement such a client, that can download files from the internet through .torrent files. It involves deep knowledge of networking and an understanding of peer-2-peer communication using the BitTorrent protocol.

How to install

cargo install --path crates/mim

How to run

mim is a command line application. You can run it by typing mim in your terminal. It has two subcommands: server and download. The server subcommand starts a server that can be used to download files. The download subcommand can be used to download files from the server. You can also use the --help flag to get more information about the subcommands.

Usage: mim [OPTIONS] <COMMAND>
Commands:
  server
  download
  help      Print this message or the help of the given subcommand(s)

Options:
  -v <LOG_LEVEL>
          The loglevel [possible values: trace, debug, info, warn, error]
  -i, --tracker-refresh-interval <FORCE_TRACKER_INTERVAL>
          The interval to poll trackers, e.g. 30s. Trackers send the refresh interval when we connect to them. Often this is pretty big, e.g. 30 minutes. This can force a certain value
      --http-api-listen-addr <HTTP_API_LISTEN_ADDR>
          The listen address for HTTP API [default: 127.0.0.1:3030]
  -s, --single-thread-runtime
          Set this flag if you want to use tokio's single threaded runtime. It MAY perform better, but the main purpose is easier debugging, as time profilers work better with this one
      --disable-dht

      --disable-dht-persistence
          Set this to disable DHT reading and storing it's state. For now this is a useful workaround if you want to launch multiple mim instances, otherwise DHT port will conflict
      --peer-connect-timeout <PEER_CONNECT_TIMEOUT>
          The connect timeout, e.g. 1s, 1.5s, 100ms etc
      --peer-read-write-timeout <PEER_READ_WRITE_TIMEOUT>
          The connect timeout, e.g. 1s, 1.5s, 100ms etc
  -t, --worker-threads <WORKER_THREADS>
          How many threads to spawn for the executor
  -h, --help
          Print help
  -V, --version
          Print version

Server

server subcommand starts a server that can be used to download files. It has the following options:

Usage: mim server <COMMAND>

Commands:
start
help Print this message or the help of the given subcommand(s)

Options:
-h, --help Print help

Start

start subcommand starts the server. It has the following options:

Usage: mim server start <OUTPUT_FOLDER>

Download

download subcommand can be used to download files from the server. It has the following options:

Usage: mim download [OPTIONS] [TORRENT_PATH]...

Arguments:
[TORRENT_PATH]... The filename or URL of the torrent. If URL, http/https/magnet are supported

Options:
-o, --output-folder <OUTPUT_FOLDER>
The output folder to write to. If not exists, it will be created. If not specified, would use the server's output folder. If there's no server running, this is required
-s, --sub-folder <SUB_FOLDER>
The sub folder within output folder to write to. Useful when you have a server running with output_folder configured, and don't want to specify the full path every time
-r, --filename-re <ONLY_FILES_MATCHING_REGEX>
If set, only the file whose filename matching this regex will be downloaded
-l, --list
Only list the torrent metadata contents, don't do anything else
--overwrite
Set if you are ok to write on top of existing files
-h, --help
Print help

Resources

Fundamentals of computer networks Basics of networking course: https://in.coursera.org/learn/computer-networking Computer Networking Videos: https://www.youtube.com/playlist?list=PLpherdrLyny-zJw95jcE-uJkcsIAG1MEn Tanenbaum, Wetherall Computer Networks 5e: https://media.pearsoncmg.com/ph/streaming/esm/tanenbaum5e_videonotes/tanenbaum_videoNotes.html

The Rust Programming Language Official book: https://doc.rust-lang.org/stable/book/ Youtube Playlist: https://www.youtube.com/watch?v=OX9HJsJUDxA&list=PLai5B987bZ9CoVR-QEIN9foz4QCJ0H2Y8 https://www.youtube.com/watch?v=5QsEuoIt7JQ&list=PLSbgTZYkscaoV8me47mKqSM6BBSZ73El6

Getting to know more about torrent What is torrent: https://www.techslang.com/torrenting-what-is-it-and-how-does-it-work/

BitTorrent protocol: https://www.bittorrent.org/beps/bep_0003.html

Implemrnted

• Reading .torrent files (single-file torrents only)
• Connecting to a tracker to discover peers
• Downloading a file from multiple peers in parallel
• Queueing multiple requests with each peer for faster downloading
• Uploading files to peers, and seeding existing files from disk
• Verification of correctness of downloaded chunks
• Multi-file torrents
• Asynchronous IO on a multithreaded runtime
• Setup a listener for seeding to peers.
• DHT