Re: Revisiting Retry-After w/ 202

On Jun 3, 2010, at 7:53 AM, mike amundsen wrote:

> I know this has come up on this list in the past[1] but I was unable to find any
> clear resolution in the archives.
> 
> I have cases where the server will queue up the client's request
> (POST/PUT/DELETE) and/or start a long-running task. I some cases I
> need the response to indicate to clients that they can check the
> status/results of the processing within a certain interval (ala HTML
> "meta refresh").
> 
> I know that 202 responses SHOULD contain indications of status, a
> monitor location and/or time estimates. However I want to  indicate
> the same data w/o requiring bots to "find" the information w/in the
> message body; a media-type agnostic solution.
> 
> As a temporary solution, when returning a 202 response, I include a
> Retry-After header and a Location header. Clients can activate the
> Location URI after the Retry interval expires. If the work is still in
> process, the response is (again) a 202 w/ the same control data. At
> some point the server will return a 200 (or possibly some 4xx/5xx code
> as appropriate).

Returning the 202 is wrong in the case of a GET to the status resource.

> 
> Is there a more appropriate solution?

What is the problem with defining an appropriate 202 body media type for non-GUI user agents? After all, you tie your user agent code to your special header combinations and associated expectations anyway.

Jan

> - Using 302 instead of 202? Even in the first response to the POST/PUT/DELETE?
> - Using Cache-Control:max-age instead of Retry-After?
> 
> Finally, is it considered harmful to use Retry-After and/or Location
> headers w/ a 202 response?
> 
> mca
> http://amundsen.com/blog/
> http://mamund.com/foaf.rdf#me
> 
> [1] http://lists.w3.org/Archives/Public/ietf-http-wg/2009JulSep/0260.html
> 

-----------------------------------
 Jan Algermissen, Consultant
 NORD Software Consulting

 Mail: algermissen@acm.org
 Blog: http://www.nordsc.com/blog/
 Work: http://www.nordsc.com/
-----------------------------------

Received on Thursday, 3 June 2010 06:11:28 UTC