Cast for two

Saturday, May 02, 2009

links to JPEG images in ATOM feed entries must be typed image/jpeg

After some debugging, I found a nasty bug in an ATOM feed that validated by the W3C validator service. I was trying to parse image url's out of an ATOM feed. ATOM 1.0 feeds are defined by the RFC 4287. In paragraph " The "type" Attribute" it is defined that the type must conform to the syntax of a MIME media type. The MIME media type is in turn defined by RFC 4288. Media type registrations are listed by the IANA at:
If we look up the media subtypes of image/ we find that JPEG images have MIME type image/jpeg . The feed I was parsing had images with MIME type image/jpg instead of image/jpeg as it should have been. Apparently the W3C validator does not validate the type of links. I reported the bug/unconformence. Hopely it will be fixed soon.
A handy list with all MIME types to be used as reference is also provided by w3cschools.