fastcgi_cache_key with cookie

[zenw]

I've  also tried this using the userid module I set a custom cookie like
so

userid on;
userid_name "testid";
userid_expires 100s;

and set the fastcgi_cache_key like so

fastcgi_cache_key $cookie_testid$request_method$scheme$host$request_uri

the problem with this setup is when I login or logout, since the key is
based on only $cookie_testid without $http_cookie, then the user will
still see the logged in page even after logging out.  Alternatively how
would I user the cache purge module to purge the key when the user hits
the login or logout button? this is the sample config

http {
    proxy_cache_path  /tmp/cache  keys_zone=tmpcache:10m;

    server {
        location / {
            proxy_pass         http://127.0.0.1:8000;
            proxy_cache        tmpcache;
            proxy_cache_key    $uri$is_args$args;
        }

        location ~ /purge(/.*) {
            allow              127.0.0.1;
            deny               all;
            proxy_cache_purge  tmpcache $1$is_args$args;
        }
    }
}

not sure how to rewrite the url.

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,220510,220520#msg-220520