Flickr Developer Blog: API Responses as Feeds (via) Flickr API calls that return a “standard photos response” (e.g. flickr.photos.search and flickr.favorites.getList) can now output eight different feed formats as well, including Atom, RSS flavours, geoatom, geordf and KML. Error codes are returned as X-FlickrErrCode HTTP headers.
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Error codes in a proprietary HTTP header. How excellent. How RESTful. Not.
AU: You don't really deserve a response as you just whined about slavish adherence to an abstract design principle without concrete feedback, but ...
Like most of the off-doctrine choices we make, that one was made working with real developers, and deployed libraries.
I'll probably also had the human readable error message to the body, but as I'm sure you know, that's officially frowned upon in some drafts of HTTP (not that the argument not to do it)
kellan - 26th August 2008 12:59 - #
Kellan: I take your critizism with regard to not being constructive. Had the API been flawlessly architected, following all the RESTful principles, with nothing else to point my finger at than this proprietary HTTP header, I would probably have been a bit more constructive in my feedback.
However, the Flickr API is such a mess and mix between REST and RPC that the proprietary HTTP header is just the tip of the iceberg. Sorry for not constructively deconstructing the whole iceberg and instead only pointing at the top of it, but other people have done it before me so I hopefully don't have to.