W3C home > Mailing lists > Public > www-tag@w3.org > May 2002

Re: Proposed TAG Finding: Internet Media Type registration, consistency of use

From: Tim Bray <tbray@textuality.com>
Date: Thu, 23 May 2002 14:58:48 -0700
Message-ID: <3CED6618.5050404@textuality.com>
To: Tantek Çelik <tantek@cs.stanford.edu>
Cc: www-tag@w3.org
Tantek Çelik wrote:
>>http://www.w3.org/2001/tag/2002/0129-mime

> While it is a laudable goal to avoid and/or limit sniffing when at all
> possible, unsubstantiated comments like these are inflammatory at best, and
> horribly naive at worst - given how many HTML (.html etc.) pages are still
> served as text/plain. (Nevermind GIFs and other images served as
> text/plain).

Tantek's comments ought to be taken seriously if for no other reason 
that he's one of the people behind arguably the world's most 
standards-compliant user-agent, namely IE for the Mac.  I do sense a 
slight tension between his admirable track record of Doing the Right 
Thing and Taking the Consequences and his position here...

Anyhow, for the moment I stand by the position that sniffing is always 
without exception bad when you're figuring out how to do top-level 
dispatch.  It opens horrible security holes and when breakage does 
occur, it focuses the blame away from where it belongs, namely people 
who screw up in configuring their webservers.  I think if someone serves 
a gzipped file or an XML file or a plain text file as text/html, or an 
HTML file as text/plain, then this *should* break visibly in users' 
browsers.  Similarly if they serve an HTML file as text/plain.  Why? 
Well, that's Tantek's next point.

>   "Web software SHOULD NOT attempt to recover from such errors by guessing,
> but SHOULD report the error to the user to allow intelligent corrective
> action."
> 
> Typically a user of a web site does not have the ability to correct the
> website itself.  Nevermind perform an "intelligent corrective action".
> Which usability genius decided that it was a good idea to report errors to
> the user that are meaningless to the typical user (typical user has zero
> knowledge about mime types) and the user has no chance of fixing?
> 
> If a UA did report such errors with a web site, the typical user would take
> the corrective action they usually take when errors are reported from a
> website, and that is to try a different UA.

No.  Most people are only vaguely aware that there are other browsers 
than what they're using, and on your typical off-the-shelf Wintel or Mac 
box these days, quite likely IE is all there is.

In fact, what people will do is, if they care at all about the website 
content, to try to find a way to complain (appropriate) and if they 
don't care that much, they go elsewhere (appropriate).  These both seem 
like good outcomes to me.  Much better than a user-agent deciding which 
body of code to dispatch based on whether or not the regexp 
<[tT][iI][tT][lL][eE]\s*> shows up near the top of the message body.  -Tim
Received on Thursday, 23 May 2002 17:58:44 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Thursday, 26 April 2012 12:47:07 GMT