On 6/19/15, 14:26, "Kevin L. Mitchell" <[email protected]> wrote:
>On Fri, 2015-06-19 at 10:07 +0100, Chris Dent wrote: >> * Are there additional relevant pros and cons for the two proposals? >> * Are there additional proposals which can address the shortcomings >> in either? > >On the latter question, would using the If-Modified-Since header[1] make >any sense as a possible solution? That at least would be a standard >HTTP convention for this sort of thing, and tends to match up with the >semantics of a changes-since query parameter. First, please use the updated RFC references (https://tools.ietf.org/html/rfc7232#section-3.3) If-Modified-Since does not. That's meant for entire resources. In other words, let's say you're listing images in Glance and you do GET /v2/images And your response has HTTP/1.1 200 OK Last-Modified: some_last_modified_value In the headers, when you do GET /v2/images If-Modified-Since: some_last_modified_value Then you should either get a: HTTP/1.1 204 No Content Or HTTP/1.1 200 OK Last-Modified: new_last_modified_value (all of the images you saw before) In other words, If-Modified-Since is meant purely for the state of the resource. It's main purpose is when used in conjunction with caching. That said, changes-since is more of a "delta". If you need an analogy, think of it as an equivalent to $ git log 2015.1.0..stable/kilo It's just the deltas after a certain timestamp. Cheers, Ian __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: [email protected]?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
