WP FastCGI Cache Purger

WordPress plugin that purges the Nginx FastCGI cache — no nginx helper module required. It deletes cache files directly from PHP, so it works on any VPS where PHP has write access to the cache directory.

What it does

• Auto-purge on content changes — post/page save, delete, trash, comment add/edit, theme switch, widget or menu changes
• Admin bar "Purge Cache" button for one-click full purge (capability: manage_options, nonce-protected)
• WP-CLI commands: wp fcgipurge all and wp fcgipurge url <url>
• Targeted purge — computes the nginx cache key hash (md5("$scheme$request_method$host$request_uri")) for a URL and deletes only that file instead of the whole cache

Requirements

• WordPress 5.8+, PHP 7.4+
• Nginx with fastcgi_cache_path (see nginx-config-snippet.conf)
• PHP (www-data) must have write access to the cache directory

Installation

1. Copy wp-fastcgi-cache-purger.php into wp-content/plugins/wp-fastcgi-cache-purger/
2. Copy nginx-config-snippet.conf rules into your nginx config (instructions are in the file)
3. Activate the plugin, then go to Settings → FastCGI Purger and enter your cache path (default /var/cache/nginx/fastcgi)
4. The page tells you whether the path is writable

Cache key notes

The targeted URL purge assumes your nginx uses:

fastcgi_cache_key "$scheme$request_method$host$request_uri";

If your key is different (e.g. includes cookies or mobile variants), adjust the fcgi_cache_key_hash() function to match. Full purges always work regardless of the key.

MIT licensed.