map_cache.conf

# -*- mode: nginx; mode: flyspell-prog;  ispell-current-dictionary: american -*-

### Testing if we should be serving content from cache or not. This is
### needed for any Drupal setup that uses and external cache.

## Testing for the session cookie being present. If there is then no
## caching is to be done. Note that this is for someone using either
## Drupal 7 pressflow or stock Drupal 6 core with no_anon
## (http://drupal.org/project/no_anon).
map $http_cookie $no_cache {
    default 0;
    ~SESS 1; # PHP session cookie
}

## If you're using stock Drupal 6 without no_anon, i.e., there's a
## session cookie being served even to anonymous users, then uncomment
## the three lines below and comment the above map directive
# map $http_cookie $no_cache {
#     default 0;
#     ~DRUPAL_UID 1; # DRUPAL_UID cookie set by Boost
# }

## Set a cache_uid variable for authenticated users.
map $http_cookie $cache_uid {
    default nil; # hommage to Lisp :)
    ~SESS[[:alnum:]]+=(?<session_id>[[:graph:]]+) $session_id;
}