Purge related question

this is my "purge" nginx snippet:

location ~ /purge(/.*) { fastcgi_cache_purge WORDPRESS "$scheme$request_method$host$1"; }

If I visit: http://foodandchatter.co.za/purge I get a WordPress "Not Found" error if I visit: http://foodandchatter.co.za/purge/ I get a nginx 404 error if I visit: http://foodandchatter.co.za/?purge/culinary-innovations-grande-roche-hotel I see my homepage if I visit: http://foodandchatter.co.za/purge/culinary-innovations-grande-roche-hotel I get a nginx 404 error.

So what is the correct way to manually initiate a purge?

http://foodandchatter.co.za/purge/culinary-innovations-grande-roche-hotel should purge http://foodandchatter.co.za/culinary-innovations-grande-roche-hotel if its cached.

404 is also returned if page is not cached in first place (this can lead to confusion but that the way it is coded)

Before you run purge - just check if page was cached. May be you can use http://rtcamp.com/wordpress-nginx/tutorials/nginx/upstream-cache-status-in-response-header/