# Metatorrent

A BitTorrent metainfo decoder.

Metatorrent decodes metainfo files (also known as .torrent files),
and sticks some additional useful information into the map,
like the info hash, and the total length for multi-file torrents.

For example, here's the [linuxmint-18.3-cinnamon-64bit.iso](https://linuxmint.com/edition.php?id=246) metainfo file, decoded:

```elixir
iex> Metatorrent.decode(File.read! "linuxmint-18.3-cinnamon-64bit.iso.torrent")
%Metatorrent.Metainfo{
  announce: "https://torrents.linuxmint.com/announce.php",
  announce_list: [],
  nodes: [],
  comment: nil,
  created_by: "Transmission/2.84 (14307)",
  creation_date: ~U[2017-11-27 09:27:31Z],
  info: %Metatorrent.SingleFileInfo{
    length: 1899528192,
    md5sum: nil,
    name: "linuxmint-18.3-cinnamon-64bit.iso",
    piece_length: 1048576,
    pieces: [
      <<167, 53, 69, 58, 13, 103, 134, 251, 174, 104, 105, 210, 94, 112, 197, 52,
  205, 246, 155, 130>>,
      ...
    ]
  },
  info_hash: <<210, 229, 63, 182, 3, 101, 45, 153, 25, 145, 182, 173, 35, 87,
    167, 162, 132, 90, 83, 25>>
}
```

### Supported BEPs

This library was built for [Effusion](https://github.com/cantido/effusion)
and so only supports the BEPs that Effusion supports.
[Full list of BEPs](http://www.bittorrent.org/beps/bep_0000.html).

| BEP | description |
| --- | --- |
| 0003 | The BitTorrent Protocol Specification |
| 0005 | DHT Protocol |
| 0012 | Multitracker Metadata Extension |

## Installation

If [available in Hex](https://hex.pm/docs/publish), the package can be installed
by adding `metatorrent` to your list of dependencies in `mix.exs`:

```elixir
def deps do
  [
    {:metatorrent, "~> 0.1.0"}
  ]
end
```

Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
be found at [https://hexdocs.pm/metatorrent](https://hexdocs.pm/metatorrent).