Further note:

as= and xs= are compatible with the sha1 Magnets. But not btih ones.

Minimal example for an SHA1 Magnet:
xt=urn:sha1:<file's base32 encoded sha1 hash>&xl=<file's size>&dn=<file's 
name>&as=<source>

The hashes that our current magnet links contain are not optimal.

(Info by Harold Feit following below.)


- BTIH + MD5 magnets don't work that well
- although we CAN get away with it on single-file torrents
- it would never work right on batches
- and clients that support magnets, but not torrent magnets don't use MD5 as their 
search key
- they usually use SHA1
- which, in a magnet, needs to be Base32 encoded

On the URL http://opensource.depthstrike.com/, several examples can be found.

mediatype changed to "torrent". See metalink-discussion list for further
discussion.

Example:


 % curl -s "http://192.168.0.115/extended/3.1.1rc2/OOo_3.1.1rc2_20090820_Win32Intel_langpack_sw-TZ.exe?meta4" | grep magnet
    <metaurl mediatype="magnet">magnet:&xl=24822941&dn=OOo_3.1.1rc2_20090820_Win32Intel_langpack_sw-TZ.exe?xt=urn:sha1:0e1aefc1df0ba4c147fb36d3c62d000441e6b945?xt=urn:bith:0e1aefc1df0ba4c147fb36d3c62d000441e6b945&xt=urn:md5:c7feb5365c2e9ce205ba212c6fa19aa0</metaurl>

Basic magnet links implemented in new metalinks now. (r7988)

I think the magnet links should be shown in the mirror list as well.

Also there should be a handler that replies with the magnet link (or
redirects to one??) when .magnet is appended to an URL. Is that
possible?

Ah, I'm relieved:

http://wiki.bitcomet.com/Peers,_seeds,_torrent,_tracker,_DHT,_Peer_Exchange_(PEX),_Magnet_Links
  The first implementations for Magnet Links required that the
  BitTorrent hash values contained in Magnet Links be Base32
  encoded.^[7] Later that was changed to hex encoding, which is the
  format recommended at this point for magnet links by the official
  BitTorrent specifications.^[8]
  [8] http://www.bittorrent.org/beps/bep_0009.html#magnet-uri-format

For Magnet links, we need to base32-encode stuff in Apache.

>>> h = hashlib.sha1()
>>> h.update('asdf')
>>> base64.b32encode(h.digest())
'HWSUCVMZDCUARQSAFO5FAEXWYYFSOZQ4'

Issue #40 is resolved far enough so to not block this change anymore.

For now, this is blocked by issue 40.

The planned redesign of the hash cache will (should) also allow to trivially add 
magnet links into metalinks.

See http://en.wikipedia.org/wiki/Magnet_URI_scheme