On Sunday, April 3, 2005, at 11:05 AM, Brett Lindsley wrote:
Consider a feed returned as a result of a search operation (e.g. a time range). To create an alternate representation of this resource, the link must also specify the same conditions that resulted in the search results. That is, the alternate link needs to somehow embed the search conditions of the search that created the feed so the server can provide an alternate representation. One way to fix this would be to indicate in the protocol spec that the same http headers must be provided to the alternate link as those used to request the feed.
If we want the link to point to something that's strictly an alternative representation of the same data, then that makes sense, but it seems to me that the link is pointing to another view into the same data stream, which could be different in more ways than just the data format. For example, following the alternate link may get you a homepage containing entries that were added after you downloaded the feed. In that case, the homepage is certainly not an alternative representation of the same data. Just as the feed or homepage contents may be different depending on when you access them, I think our definition of "alternate" is loose enough to allow differences based on HTTP headers.
