Re: [Connotea-code-devel] webapi: 404 on empty query

[Robert F. <xro...@go...>]

my intuition would certainly speak against 404 "no items found". in
fact, i added the handler for 404 responses to valid query requests
after running into the problem. 0 matching results does not feel
qualitatively different to 10 matching results. and i think it's the
query context - thus something client side - which decides whether 0
results means there's something wrong. i also think http responses in
the 4xx range indicate exactly this: something's wrong.

probably worth a different post: i think there should be a way to post
citation data. i.e. the body of a request adding/updating a post
should not be url parameters, but an xml document like the one
returned for querying posts.

robert

On 6/1/06, Lund, Ben <b....@na...> wrote:
> Hi Robert,
>
> On 25/5/06 21:12, "Robert Forkel" <xro...@go...> wrote:
> > hi,
> > while testing my api wrapper, i ran into a problem with the webapi:
> > queries for tags/posts/bookmarks return 404 if no matches have been
> > found. to cater for this, the wrapper tried to parse a webapi response
> > for this http status code. for some requests - e.g. for non-existing
> > users like http://www.connotea.org/data/bookmarks/user/http
> > - only the apache default 404 page is returned, which can't be parsed
> > as webapi response.
>
> Hmm, thanks. That's definitely a bug.  A response XML document should
> definitely be returned, whatever the appropriate status code.  It looks like
> it only happens when there's a user in the request (see, for example,
> http://www.connotea.org/data/tag/gfdgffdgfdgfdfgd for what it should look
> like).
>
> We'll fix that.
>
> > so i'd propose to return 200 with a webapi
> > response saying "no items found" for empty searches, or simply empty
> > result xml?
> > what do you think?
>
> Looking through the HTTP spec, the following codes are likely candidates:
>
> 200 OK - with an empty XML document
> 204 No content - with no body at all
> 400 Bad request - indicates that the tag or username in invalid
> 404 Not found - indicates that the tag or user is unknown
>
> Looking through these, 400 seems too harsh -- the request was valid syntax,
> just resulting in no items.  204 looks good, but we wouldn't be to put a
> Response body, nor explain exactly why there is no content.
>
> I'm not sure about 200. If we included an empty XML doc as the response we
> again wouldn't be able to give details on why there were no results. If we
> included a response doc instead, that complicates the parsing a little,
> since the client needs to check the status code and also the root XML
> element before knowing what to do next.
>
> So I'm leaning towards sticking with 404 - given that either that tag or the
> user were not found, I think it matches the intended meaning well.
>
> But I'm willing to be convinced -- what do you think?
>
> > robert
>
> Ta,
> Ben
>
>
> ********************************************************************************
> DISCLAIMER: This e-mail is confidential and should not be used by anyone who is
> not the original intended recipient. If you have received this e-mail in error
> please inform the sender and delete it from your mailbox or any other storage
> mechanism. Neither Macmillan Publishers Limited nor any of its agents accept
> liability for any statements made which are clearly the sender's own and not
> expressly made on behalf of Macmillan Publishers Limited or one of its agents.
> Please note that neither Macmillan Publishers Limited nor any of its agents
> accept any responsibility for viruses that may be contained in this e-mail or
> its attachments and it is your responsibility to scan the e-mail and
> attachments (if any). No contracts may be concluded on behalf of Macmillan
> Publishers Limited or its agents by means of e-mail communication. Macmillan
> Publishers Limited Registered in England and Wales with registered number 785998
> Registered Office Brunel Road, Houndmills, Basingstoke RG21 6XS
> ********************************************************************************
>