Mail address obscurification via <img > tags

[raimo_niskanen]

While replacing majordomo + mhonarc with mailman we had
(at www.erlang.org) an own email address
obscurification that created .png file for all email
addresses and inserted <img > tags in the mhonarc HTML
archives.

I have now reimplemented that for pipermail in mailman
using the Python Imaging Library
(http:/www.pytonware.com/products/pil).

The patch is for mailman 2.1.6 in OpenBSD 3.8.

I have introduced
mm_cfg.ARCHIVER_OBSCURES_EMAILADDRS_FONT that if not
False is a path to a .pil font activating email address
obscurification by <img > tags.

The email addresses are stored in
/var/spool/mailman/archives/private/%(listname)s/emailaddrs/
as files named %06s.png. Handling of this directory
should probably be moved to Archiver/HyperDatabase.py,
but I wanted to concentrate my changes to one file.

pipermail.pck contains a dictionary to map email
address to image index number. If this makes the file
to large, the dictionary should perhaps be moved to a
file in the database/ directory but OTOH that directory
contains only files per archive period.

The patch needs improvement regarding i18n. Perhaps it
is enough to be able to select obscurification font per
list, or maybe font variant should be automatically
selected depending on encoding. I have virtually no
previous experience of i18n issues.

The patch also removes the domain name for all email
addresses in the downloadable text archive, like
mhonarc does in <SPAMMODE>.

All this because i am convinced the <user at dom.ain>
rewriting is too easy to harvest.

This patch works for me, and I am sure others would
benefit from it or something equivalent.

/ Raimo Niskanen, Ericsson AB, Erlang/OTP

[raimo_niskanen (raimo-niskanen)]

The file obscure-png.diff was added: diff -c Mailman/Archiver/HyperArch.py{.ORIG,}