In

jQuery.ajax

, the function

done()

is executed when the ajax request is completed (successfully or not).

done()

function always evaluates the content received from the xhr call into the variable

response

(line 9260).

That

response

is only accessible to high-level callbacks when

isSuccess

variable evaluates to

true

(line 9309).

isSuccess

is set according to the following rules (line 9252) :

• if the ajax request is aborted or fails,

  isSuccess

  is

  false

• if the ajax request successes and the status code is

  2xx

  or

  304

  ,

  isSuccess

  is

  true

• if the ajax request successes and the status code is otherwise,

  isSuccess

  is

  false

Additionnaly,

isSuccess

reverts to

false

if parsing the response content failed (line 9290).

This poses a problem when one tries to use

$.ajax()

for REST requests. A REST response may provide useful content with many status codes, including 301, 404, 500, etc.

There are multiple ways to interpret the problem, however I suggest a really simple and retro-compatible solution.

The following will escape the status check with an additionnal option

inclusiveSuccess

:

line 8928 :

--- context: true
+++ context: true,
+++ inclusiveSuccess: false

line 9252 :

--- isSuccess = status >= 200 && status < 300 || status === 304;
+++ isSuccess = status >= 200 && status < 300 || status === 304 || status > 0 && s.inclusiveSuccess;

The consequences of this solution are extensive :

• success}} callback will be called for every status code, given that the ajax request succeeded and the content is parsed successfully.
  * all {{{statusCode

  callbacks will be called with the first argument representing parsed content (not just 2xx and 304 callbacks)

Another solution is to give access to

ajaxHandleResponses()

and

ajaxConvert()

functions, which currently are not accessible outside the jQuery definition. With this workaround, it would be possible to manage the response through the

complete

callback and its

jqXHR

argument.

A third solution would be to develop a specific

$.rest()

client interface, with a dedicated behavior.