On Apr 20, 2012, at 12:09 PM, Richard Wackerbarth wrote: >As for the "opaque" hash, the order is not important. The order of the inputs >is arbitrary. It needs to be fixed and published so that multiple encoders >will derive the same hash as that generated by another encoder.
Right. I've updated the description of bug 985149 to be explicit about the proposal. I like Permalink-Hash as the header name. https://bugs.launchpad.net/mailman/+bug/985149 >If the List ID made a visible part of the message identifier, then it is >creating a separate namespace for each list. Here the order may have >implications when viewed in the context of other uses. > >Here, we might be wish to be able to have only one copy of the message in the >archive and/or the distribution channels even when that message gets >cross-posted to multiple lists. Note that RFC 5064 defines the Archived-At header. IMO, this would be the appropriate place to add any list-specific namespace discriminator. Also, RFC 2369 defines the List-Archive header, which could contain the base URL to the archiver, including the List-ID information. >The one thing that does need to be visible is the designation of the revision >of the hashing algorithm. Otherwise, without that visible indicator, there is >no way to recreate a "stable" value if a rehashing needs to be performed. Yep, see the bug for details. Below is an example in Python code. Cheers, -Barry >>> from email import message_from_string as mfs >>> msg = mfs("""\ ... To: myl...@example.com ... Message-ID: <foo> ... ... """) >>> from hashlib import sha1 >>> from base64 import b32encode >>> bare_msgid = msg['message-id'][1:-1] >>> bare_msgid 'foo' >>> msg['List-ID'] = '<mylist.example.com>' >>> bare_listid = msg['list-id'][1:-1] >>> bare_listid 'mylist.example.com' >>> h = sha1(bare_msgid) >>> h.update(bare_listid) >>> permalink_hash = b32encode(h.digest()) >>> permalink_hash 'FW7VLQIZV3P6O64PL7OGLM5Y3RUBQZ4F' >>> msg.add_header('Permalink-Hash', permalink_hash, version='1') >>> msg['permalink-hash'] 'FW7VLQIZV3P6O64PL7OGLM5Y3RUBQZ4F; version="1"' >>> msg['List-Archive'] = 'http://list.example.com/{}'.format(bare_listid) >>> msg['list-archive'] 'http://list.example.com/mylist.example.com' >>> msg['Archived-At'] = '{}/{}'.format(msg['list-archive'], permalink_hash) >>> msg['archived-at'] 'http://list.example.com/mylist.example.com/FW7VLQIZV3P6O64PL7OGLM5Y3RUBQZ4F' _______________________________________________ Mailman-Developers mailing list Mailman-Developers@python.org http://mail.python.org/mailman/listinfo/mailman-developers Mailman FAQ: http://wiki.list.org/x/AgA3 Searchable Archives: http://www.mail-archive.com/mailman-developers%40python.org/ Unsubscribe: http://mail.python.org/mailman/options/mailman-developers/archive%40jab.org Security Policy: http://wiki.list.org/x/QIA9
