Proxying to node.js + express.js, session doesn't persist

[ilya]

Here's what I see in the browser
---------Logging in-------------

Request Headers
Host	173.203.105.235
User-Agent	Mozilla/5.0 (Windows NT 6.1; rv:5.0) Gecko/20100101
Firefox/5.0
Accept	*/*
Accept-Language	en-us,en;q=0.5
Accept-Encoding	gzip, deflate
Accept-Charset	ISO-8859-1,utf-8;q=0.7,*;q=0.7
Connection	keep-alive
Content-Type	application/json; charset=UTF-8
X-Requested-With	XMLHttpRequest
Referer	http://173.208.105.235/api.html
Content-Length	87

-----------------------------

Response Headers
Server	nginx/1.0.4
Date	Thu, 21 Jul 2011 14:55:06 GMT
Transfer-Encoding	chunked
Connection	keep-alive
X-Powered-By	Express
Set-Cookie	wdialef51s00s=4edaae8b004e0c6d740968fd6b7f9c89c23b5a2a0d373de44a937605899127bc;
path=/; expires=Thu, 21 Jul 2011 15:10:06 GMT; httpOnly
connect.sid=L96yGUBwoDwrQLqm2xlhBsZB.XHduhuaqAHqocaN6%2F0gCKQG6uiZtPb1UsSdGRTFpxgM;
path=/; expires=Thu, 21 Jul 2011 15:05:11 GMT; httpOnly
--------------------------------

Login successful. As you can see, connect.id cookie is set (this is what
Express.js session uses). Now, I make a request to resource where
session is checked:

--------------------------------
Request Headers
Host	173.203.105.235
User-Agent	Mozilla/5.0 (Windows NT 6.1; rv:5.0) Gecko/20100101
Firefox/5.0
Accept	*/*
Accept-Language	en-us,en;q=0.5
Accept-Encoding	gzip, deflate
Accept-Charset	ISO-8859-1,utf-8;q=0.7,*;q=0.7
Connection	keep-alive
X-Requested-With	XMLHttpRequest
Referer	http://173.208.105.235/api.html
Cookie	wdialef51s00s=4edaae8b004e0c6d740968fd6b7f9c89c23b5a2a0d373de44a937605899127bc;
connect.sid=L96yGUBwoDwrQLqm2xlhBsZB.XHduhuaqAHqocaN6%2F0gCKQG6uiZtPb1UsSdGRTFpxgM

-------------------------------

Response Headers
Server	nginx/1.0.4
Date	Thu, 21 Jul 2011 14:56:09 GMT
Transfer-Encoding	chunked
Connection	keep-alive
X-Powered-By	Express
Set-Cookie	connect.sid=L96yGUBwoDwrQLqm2xlhBsZB.XHduhuaqAHqocaN6%2F0gCKQG6uiZtPb1UsSdGRTFpxgM;
path=/; expires=Thu, 21 Jul 2011 15:05:11 GMT; httpOnly

-------------------------------

Now, I just stumbled upon something I didn't notice yesterday: the
property that I save on request session - the one that I can't get to
work - apparently DOES work sometimes. Basically, if I keep logging in
and requesting resource - it works on some attempts. However, if I keep
requesting the resource after successful attempt - it breaks after few
requests and session goes back to original state.

This is just bizarre.

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,212747,212763#msg-212763