Why is jquery's .ajax() method not sending my session cookie?

Question

After logging in via $.ajax() to a site, I am trying to send a second $.ajax() request to that site - but when I check the headers sent using FireB

Answer 1

Put this in your init function:

$.ajaxSetup({
  xhrFields: {
    withCredentials: true
  }
});

It will work.

Answer 2

There are already a lot of good responses to this question, but I thought it may be helpful to clarify the case where you would expect the session cookie to be sent because the cookie domain matches, but it is not getting sent because the AJAX request is being made to a different subdomain. In this case, I have a cookie that is assigned to the *.mydomain.com domain, and I am wanting it to be included in an AJAX request to different.mydomain.com". By default, the cookie does not get sent. You do not need to disable HTTPONLY on the session cookie to resolve this issue. You only need to do what wombling suggested (https://stackoverflow.com/a/23660618/545223) and do the following.

1) Add the following to your ajax request.

xhrFields: { withCredentials:true }

2) Add the following to your response headers for resources in the different subdomain.

Access-Control-Allow-Origin : http://original.mydomain.com
Access-Control-Allow-Credentials : true

Answer 3

I was having this same problem and doing some checks my script was just simply not getting the sessionid cookie.

I figured out by looking at the sessionid cookie value in the browser that my framework (Django) was passing the sessionid cookie with HttpOnly as default. This meant that scripts did not have access to the sessionid value and therefore were not passing it along with requests. Kind of ridiculous that HttpOnly would be the default value when so many things use Ajax which would require access restriction.

To fix this I changed a setting (SESSION_COOKIE_HTTPONLY=False) but in other cases it may be a "HttpOnly" flag on the cookie path

Answer 4

Using

xhrFields: { withCredentials:true }

as part of my jQuery ajax call was only part of the solution. I also needed to have the headers returned in the OPTIONS response from my resource:

Access-Control-Allow-Origin : http://www.wombling.com
Access-Control-Allow-Credentials : true

It was important that only one allowed "origin" was in the response header of the OPTIONS call and not "*". I achieved this by reading the origin from the request and populating it back into the response - probably circumventing the original reason for the restriction, but in my use case the security is not paramount.

I thought it worth explicitly mentioning the requirement for only one origin, as the W3C standard does allow for a space separated list -but Chrome doesn't! http://www.w3.org/TR/cors/#access-control-allow-origin-response-header NB the "in practice" bit.

Answer 5

Perhaps not 100% answering the question, but i stumbled onto this thread in the hope of solving a session problem when ajax-posting a fileupload from the assetmanager of the innovastudio editor. Eventually the solution was simple: they have a flash-uploader. Disabling that (setting

var flashUpload = false;   

in asset.php) and the lights started blinking again.

As these problems can be very hard to debug i found that putting something like the following in the upload handler will set you (well, me in this case) on the right track:

$sn=session_name();
error_log("session_name: $sn ");

if(isset($_GET[$sn])) error_log("session as GET param");
if(isset($_POST[$sn])) error_log("session as POST param");
if(isset($_COOKIE[$sn])) error_log("session as Cookie");
if(isset($PHPSESSID)) error_log("session as Global");

A dive into the log and I quickly spotted the missing session, where no cookie was sent.

Answer 6

After trying out the other solutions and still not getting it to work, I found out what the problem was in my case. I changed contentType from "application/json" to "text/plain".

$.ajax(fullUrl, {
    type: "GET",
    contentType: "text/plain",
    xhrFields: {
         withCredentials: true
    },
    crossDomain: true
});