dir2rss -- lightweight server for turning a folder into a feed, primarily for iTunes

language: Ruby
platform: POSIX-compatible, generally OS X
license: GPLv3

If you use iTunes, you may find that for non-music files, it is generally
easier if they arrive as podcasts. You can't add this audio miscellany to
podcasts - either you have to categorise it as an audiobook or you have to keep
it as music. Having a 'misc' feed would be very useful for all the audio
clutter one finds in one's ~/Downloads folder. I've been meaning to build
something like this for a while, but then James O'Malley (Psythor on Twitter)
suggested it.

At http://twitter.com/Psythor/status/13249291825, James O'Malley wrote:
> Does this exist: podcast RSS feeds generated from local Mac OS folder, so
> MP3s I download can dump to the same folder and listen as podcast?

PREREQUISITES
-------------

Ruby 1.8 (haven't tested it with 1.9)
- if you are using OS X, you'll have 1.8.7 by default

Gems:
- builder
- mp3info
- mongrel

(On OS X: sudo gem install mongrel etc.)

Knowledge of how to operate your firewall.

crontab turned on.

USAGE
-----

dir2rss_gen.rb is the script which converts your nominated folder into an RSS
2.0 feed and puts that out on STDOUT. You need to pipe this into an output
file. Given that you are probably interested in your Downloads folder, here's
how you'd formulate that.

Put your dir2rss_gen.rb script in the downloads folder.

ruby ~/Downloads/dir2rss_gen.rb > ~/Downloads/dir2rss.xml

You should put this in your crontab:

*/5 * * * *  ruby ~/Downloads/dir2rss_gen.rb > ~/Downloads/dir2rss.xml

The "*/5" part means every 5 minutes. One can change it to 10, 15, 20 etc.

Read http://en.wikipedia.org/wiki/Cron to learn about crontab.

This will basically run the RSS generation script every five minutes. Sometime,
I'd like to do this with FSEvents (or Linux's inotify, or Windows' File
Alternation Monitor API or kqueues) but that was too much work for a Sunday
afternoon. But if I can be bothered, this would make it so that as soon as the
nominated folder is updated (i.e. when you download a file), it would re-run
the generation script.

The generation script is easy enough: it has some fancy FP lambda stuff which
is because I want to show that I'm really a Lisp weenie in a Ruby weenie's
body. The audio_only variable designates whether it looks only for audio
(anything that ends in mp3 or m4a) or video too (mp4, mov, m4v). I've excluded
PDFs even though they conform to iTunes' requirements. Why? Because PDFcasts
are totally stupid. Why do I want to read PDFs in my media player? That's about
as useful as having chocolate on my pizza.

What makes this difficult is that you have to serve everything from HTTP:
iTunes just doesn't deal with file:. It can't read an XML file served from
file: and it certainly can't read the media files from there.

Basically you need to generate your XML file and serve that from an HTTP server
and you need to serve the media itself from an HTTP server.

So you need to run a server. I've included a script to run a Mongrel server,
but I can't get it to run. The other alternatives are to use a WEBrick server,
to setup OS X's Apache as a server or to use Python's SimpleHTTPServer (I like
that option and use it myself when I need to run simple web servers for
chucking files around).

SEE ALSO
--------

Huffduffer - does something very similar. Basically a media bookmarking system,
sort of like Instapaper for audio. ;)
http://huffduffer.com -- created by @adactio 

CONTACT
-------

Tom Morris <tom@tommorris.org>

PayPal appreciated.