How to open magnet torrent links from Firefox in rTorrent?

Question

I am using the command-line torrent client rTorrent under Xenial Xerus and I would like to:

1. Find and click on a magnet torrent link with Firefox
2. Have the magnet link opened automatically in rTorrent and start downloading

I believe a script is needed to be called from within Firefox, but the writing of such a script has so far defeated me...

Solution 1

The problems usually lie with mime type and default handlers.

Firstly, have you changed Firefox's about:config settings? ie:

network.protocol-handler.expose.magnet -> false

and reset other options as per this Firefox deluge Q&A.

Have you set up rTorrent to watch any particular directory?

FILE: ~/.rtorrent.rc

# Maximum and minimum number of peers to connect to per torrent.
min_peers = 50
max_peers = 80

# Maximum number of simultanious uploads per torrent.
max_uploads = 5

# Global upload and download rate in KiB. "0" for unlimited.
download_rate = 0
upload_rate = 50

# Default directory to save the downloaded torrents.
directory = $HOME/torrents/downloads

# Watch a directory for new torrents
# SET your watch directory here --v 
schedule = watch_directory,5,5,$HOME/torrents/watch/*.torrent

port_range = 60125-64125
port_random = yes
dht = auto

# UDP port to use for DHT.
dht_port = 63425

# Enable peer exchange (for torrents not marked private)
peer_exchange = yes

# Check hash for finished torrents.
check_hash = yes

encryption = allow_incoming,try_outgoing ,enable_retry

Then it is a simple matter of "save as" into $HOME/torrents/watch.

Change $HOME/torrents/watch to whatever torrents subfolder you use, or at least $HOME to /home/username

Create a file and add the following script:

FILE: maglink-rtorrent.sh

#!/bin/bash

cd $HOME/torrents/watch    # set your watch directory here
[[ "$1" =~ xt=urn:btih:([^&/]+) ]] || exit;
echo "d10:magnet-uri${#1}:${1}e" > "meta-${BASH_REMATCH[1]}.torrent"

Don't forget to make it executable

chmod +x maglink-rtorrent.sh

This also offers the ability to download from terminal by:

cd $HOME/torrents/watch
./maglink-rtorrent.sh "MAGNET-LINK-HERE"

Further awesome Service Tips and rTorrent setup options here.

Futher credits:

• magnet links and command line 1
• magnet links and command line 2

Update 2:

If not using rTorrent, but kTorrent or qBittorent, then this following is the way to get that running:

# check defaults
xdg-mime query default x-scheme-handler/magnet
gvfs-mime --query x-scheme-handler/magnet

# set defaults
xdg-mime default qBittorent.desktop x-scheme-handler/magnet
gvfs-mime --set x-scheme-handler/magnet qBittorrent.desktop

There's a further setting (from memory) for whether you require commandline.

For rTorrent though, this link is the FlexGet rTorrent Magnet URI Handler

Full information here.

Hope this helps.

Solution 2

The following script is a spin on Max Gonzih's code that works both with regular .torrent files and magnet links:

#!/bin/bash

torrent_file_or_magnet_link="$1"

# Edit rtorrent.rc to automatically start downloads when a .torrent file
# appears in this directory.
cd "$HOME/.rtorrent/watch/start/"

# XT stands for "exact topic".
# BTIH is the BitTorrent info hash:
# https://en.wikipedia.org/wiki/Magnet_URI_scheme#BitTorrent_info_hash_(BTIH)
# This is the hex-encoded SHA-1 hash of the torrent file info section
magnet_regex="xt=urn:btih:([^&/]+)"
if [[ "$torrent_file_or_magnet_link" =~ $magnet_regex ]]; then
  torrent_hash=${BASH_REMATCH[1]};
  magnet_link_length=${#torrent_file_or_magnet_link}
  # To conform with the bencode encoding, the magnet link's number of characters
  # must be part of the torrent file, otherwise rTorrent can't read it.
  # Same for the "e" at the end.
  # See https://en.wikipedia.org/wiki/Bencode
  torrent_file_content="d10:magnet-uri${magnet_link_length}:${torrent_file_or_magnet_link}e"

  # Note that rTorrent will read this torrent file, start downloading
  # the file and then remove the torrent file
  echo "$torrent_file_content" > "$torrent_hash.torrent"
else
  cp "$torrent_file_or_magnet_link" .
fi

You can use this in a script (let's call it pass_to_rtorrent.sh) and have Firefox pass the torrent file or magnet link to the script:

Make sure the script is executable: chmod +x pass_to_rtorrent.sh

Comments

[andrew.46]

Indeed this is what I am doing at the moment but I am after a more automated approach...

[eri0o]

Check support.mozilla.org/en-US/questions/1012864

[andrew.46]

I have managed to crack this one on my own using: paxmontem.blogspot.com.au/2012/03/… but I would be more than happy to award the bonus if you can bend your answer this way...

[greg.arnott]

Ha! I was going to add that script to my answer, but chose not to for it being a terminal option - where I thought you were after a pure browser one-click option. link

[andrew.46]

Not so much the terminal script on the bottom of your link. Looks like the Browser can be set to pass the magnet link to a script to clean it up and pass it to the rtorrent watch directory. I used this page: paxmontem.blogspot.com.au/2012/03/… but it all feeds off the ARCH wiki page...