Silly behavior of accept headers and mimetypes

herenvardo · 08-11-2008, 01:56 PM

I'm developing a standards-compliant site and IE isn't helping to make it easier.
To begin with, the site is XHTML strict. I know IE is capable of rendering this type of document (although with some limitations on the CSS support), but according to the W3 Consortium the mime type for these documents should be application/xml+xhtml. If I send something else on the Content Type header, the W3C HTML validator will complain about it (and perfect validation with no warnings is a must for this project). However, sending the correct header will cause IE to display the "Save" dialog box instead of rendering the page.
I thought I could use content negotiation and dinamically generate a HTML 4 (which is not the same as serving XHTML as text/html: for this project, serving content with wrong mimes is unacceptable) version of the page for those browsers who can't swallow XHTML properly, but when I tried to use the Accept header to do this in a generic way, IE surprised me with: "image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash, application/x-ms-application, application/x-ms-xbap, application/vnd.ms-xpsdocument, application/xaml+xml, application/x-silverlight, application/vnd.ms-excel, application/msword, */*"

Literally speaking, IE is telling my server that it doesn't accept neither HTML nor XHTML pages. According to the HTTP specification, the only "correct" things I could do here are:

Serve the default/preferred content, which in this case is application/xml+xhtml, and hope the "*/*" is there for something.
Serve a "406: Unacceptable" status code, and optionally add a message in the content explaining the cause of the error.

Putting it all together, both options leave IE users out of this site. Or, in other words, it is impossible to serve XHTML to IE without seriously breaking the standards.

I wonder if there exists any way to fix this silly behavior, or if there are any plans to make such fix on further versions or service packs; since this behavior is, strictly speaking, wrong; and quite annoying.

08-11-2008, 01:56 PM	#1 (permalink)
herenvardo Registered User Join Date: Aug 2008 Posts: 1 OS: xp sp3, kubuntu+wine, FreeDOS	Silly behavior of accept headers and mimetypes I'm developing a standards-compliant site and IE isn't helping to make it easier. To begin with, the site is XHTML strict. I know IE is capable of rendering this type of document (although with some limitations on the CSS support), but according to the W3 Consortium the mime type for these documents should be application/xml+xhtml. If I send something else on the Content Type header, the W3C HTML validator will complain about it (and perfect validation with no warnings is a must for this project). However, sending the correct header will cause IE to display the "Save" dialog box instead of rendering the page. I thought I could use content negotiation and dinamically generate a HTML 4 (which is not the same as serving XHTML as text/html: for this project, serving content with wrong mimes is unacceptable) version of the page for those browsers who can't swallow XHTML properly, but when I tried to use the Accept header to do this in a generic way, IE surprised me with: "image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash, application/x-ms-application, application/x-ms-xbap, application/vnd.ms-xpsdocument, application/xaml+xml, application/x-silverlight, application/vnd.ms-excel, application/msword, /" Literally speaking, IE is telling my server that it doesn't accept neither HTML nor XHTML pages. According to the HTTP specification, the only "correct" things I could do here are: Serve the default/preferred content, which in this case is application/xml+xhtml, and hope the "/" is there for something. Serve a "406: Unacceptable" status code, and optionally add a message in the content explaining the cause of the error. Putting it all together, both options leave IE users out of this site. Or, in other words, it is impossible to serve XHTML to IE without seriously breaking the standards. I wonder if there exists any way to fix this silly behavior, or if there are any plans to make such fix on further versions or service packs; since this behavior is, strictly speaking, wrong; and quite annoying.