wingolog

the merry month of ma

12 March 2012 8:27 PM (meta | tekuti | guile | scheme | http)

or, from the department of self-inflicted injuries

Recently I saw a bunch of errors in my server logs. People were asking for pages on my web site, but only if they were newer than Thu, 08 Ma 2012 22:44:59 GMT. "Ma"? What kind of a month is that? The internets have so many crazy things.

On further investigation, it seemed this was just a case of garbage in, garbage out; my intertube was busted. I was the one returning a Last-Modified with that date. It was invalid, but client software sent it back with the conditional request.

Thinking more on this, though, and on the well-known last-modified hack in which that field can be used as an unblockable cookie, I think I have to share some blame with the clients again.

So, clients using at least Apple-PubSub/65.28, BottomFeeder/4.1, NetNewsWire, SimplePie, Vienna, and Windows-RSS-Platform/2.0 should ask the people that implement their RSS software to only pass a Last-Modified date if it's really a valid date. Implementors of the NetVibes and worio.com bots should also take a look at their HTTP stacks. I don't guess that there's much that you can do with an etag though, for better or for worse.

Previously, in a related department.

2 responses

  1. ijp says:

    And who could forget the monday bug :P http://git.savannah.gnu.org/gitweb/?p=guile.git;a=commit;h=a24885b27d6c26a5ad2dfeb18eaaaf674853bbfe

  2. wingo says:

    Indeed, indeed! One wonders if these things will combine at some point: the tuesday-in-november bug, or something.

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