Just realised the section numbers have changed.
To avoid any confusion my point relates to:
Section: *Matching Requests to Resource Methods
*Bullet Point: *Identify the method that will handle the request
*Thanks,
Barry*
*
On Feb 11, 2008 3:25 PM, Barry Fitzgerald <barfitzgerald_at_gmail.com> wrote:
> Hi all,
>
> I think there is an error in the algorithm in the JAX-RS specs for
> choosing the resource method (see bullet 2. in section 2.6)
>
> Consider the following scenario:
>
> I have a resource with 2 methods:
>
> @HttpMethod("GET")
> @UriTemplate("/users/{id}")
> @ProduceMime("text/xml")
> public Response getUser(@UriParam("id") String id) throws Exception {
> ....}
>
> @HttpMethod("GET")
> @UriTemplate("/users/{id}")
> @ProduceMime("application/json")
> public Response getUserJSON(@UriParam("id") String id) throws Exception {
> ....}
>
> If I then send a request to /users/24 with Accept headers of "text/xml,
> */*" one would expect the "text/xml" method to be invoked. However following
> the algorithm in the spec it is undefined which method should be invoked.
>
> More details:
>
> In the algorithm, both methods match the accept headers i.e. they are both
> added to the list of "matching resource methods" This list is then sorted
> using the consume mime type (not relevant in this case) and then by the
> produce mime. In this case it will compare "text/xml" against
> "application/json". As both are equally specific it is undefined which
> should be first.
>
> However surely as the "text/xml" method matches the accept header
> specifically it should always be returned first? See -
> http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html for further details
>
> One solution would be to change the algorithm to the following:
>
> 1. Sort the Accept header according to the W3 standards
> 2. Iterate through the accept header list. For each one:
> 1. Find all matching methods
> 2. If there is only one method return this and break out of
> the accept header loop
> 3. If there are multiple methods sort these methods using
> consume mime and produce mime. Then return the first.
>
> Therefore when accept header of "text/xml, text/*, */*" is sent in.
> Methods matching "text/html" are first searched for then "text/*" then
> "*/*". I think this would solve the problem.
>
> This isn't some arbitrary obscure scenario.
>
> Looking at firefox's defaults it sends
> "text/xml,application/xml,application/xhtml+xml,text/html;q=0.9
> ,text/plain;q=0.8,image/png,*/*;q=0.5"
>
> Surely for a request from firefox I'd expect to get back one of the stated
> accepts not "application/widget" or "application/json"?
>
> Barry
>
>
>
>