Using an upstream header value as a proxy_cache_key

Server NGINX
1

Is it possible to have an upstream server set an HTTP header that can be
used as the key in proxy_cache_key? This doesn’t work:

            proxy_cache_key $upstream_http_x_myheader;

And neither does this:

            set $v $upstream_http_x_myheader;
            proxy_cache_key $v;

Thanks!

2

Hello!

On Thu, Dec 24, 2009 at 03:28:25PM -0800, Troy H. wrote:

Is it possible to have an upstream server set an HTTP header
that can be used as the key in proxy_cache_key? This doesn’t
work:

            proxy_cache_key $upstream_http_x_myheader;

And neither does this:

            set $v $upstream_http_x_myheader;
            proxy_cache_key $v;

It won’t, as $upstream_* variables are available only after
request to upstream while cache key must be constructable from
client request (before request to upstream, to find out if it’s
needed).

Maxim D.

3

Duh! That makes sense. :slight_smile: Thanks.