# application cache could generate static pages.
# check if the page is less than 5 minutes old and serve if from
# disk cache.
if (-M $document_root/cache$request_uri.html < 300) {
    rewrite (.*) /cache$1.html break;
}

if (-M $document_root/cache$request_uri/index.html < 300) {
    rewrite (.*) /cache$1/index.html break;
}