NGINX+Wordpress 缓存悖论

Question

I'm running Wordpress + NGINX + PHM-FPM. I've made these changes to my NGINX config, taken from a best-practices article I've encountered:

#Don't cache if there is a cookie called PHPSESSID
if ($http_cookie ~* "PHPSESSID"){
    set $no_cache 1;
}

#Don't cache if there is a cookie called wordpress_logged_in_[hash]
if ($http_cookie ~* "wordpress_logged_in_"){
    set $no_cache 1;
}

however, the means the post pages (majority of my hits) are not cached as they are requested while the PHPSESSID cookie is used. The post pages do not contain per-user context and are general. IS there a better way to allow caching for post pages only? perhaps using the "domain.com/yyyy/mm/dd/post-name" pattern?

Answer 1

This is the block I usually use to specifically disable Fast-CGI cache for Wordpress/Woocommerce site, it may help:

#disabler
set $no_cache 0;

# POST requests and urls with a query string should always go to PHP
if ($request_method = POST) {
    set $no_cache 1;
}
if ($request_method = PATCH) {
    set $no_cache 1;
}
if ($query_string != "") {
    set $no_cache 1;
}   

# Don't cache uris containing the following segments
if ($request_uri ~* "/wp-admin/|/wp-login/|/xmlrpc.php|index.php|phpmyadmin|sitemap(_index)?.xml|sitemap$") {
    set $no_cache 1;
}   
if ($request_uri ~* "(/wp-admin/|/xmlrpc.php|/wp-(app|cron|login|register|mail).php|wp-.*.php|/feed/|index.php|wp-comments-popup.php|wp-links-opml.php|wp-locations.php|sitemap(_index)?.xml|[a-z0-9_-]+-sitemap([0-9]+)?.xml)") {
    set $no_cache 1;
}
if ($request_uri ~* "(/wp-admin/|/cart/|/checkout/|/account/|/mon-compte/|/xmlrpc.php|/wp-(app|cron|login|register|mail).php|wp-.*.php|/feed/|index.php|wp-comments-popup.php|wp-links-opml.php|wp-locations.php|sitemap(_index)?.xml|[a-z0-9_-]+-sitemap([0-9]+)?.xml)") {
    set $no_cache 1;
}

# Don't use the cache for logged in users or recent commenters
if ($http_cookie ~* "comment_author|wordpress_[a-f0-9]+|wp-postpass|wordpress_no_cache|wordpress_logged_in|postpass|wordpress_n$") {
    set $no_cache 1;
}

# Woocommerce
if ($request_uri ~* "/store.*|/cart.*|/my-account.*|/checkout.*|/addons.*|/panier.*|/paiement.*|/mon-compte.*") {
    set $no_cache 1;
}

if ( $arg_add-to-cart != "" ) { 
   set $no_cache 1;
}

# need more tests
#if ( $cookie_woocommerce_items_in_cart != "0" ) {  
#   set $no_cache 1;
#}

if ( $cookie_woocommerce_items_in_cart ) {
    set $no_cache 1;
}

This is an aggregate of multiple articles and Gist I found. Note that I usually add headers in each block to see what is the one disabling cache during tests. Some rules may be duplicated.

After a log out, the user still has some cookie so sometimes, bypasses the cache. But it works correctly in most of the case.

Implementing all or part of this will, of course, need tests.

I use this among the Wordpress Nginx Helper plugin, that is really useful for a global and conditional purge.