Feature Request: NGINX's FastCGI cache

[firestrife23]

For those prefer to use NGINX's native FastCGI cache instead of php based plugins. Feel free to modify and add to globals directory.

fastcgi_cache_path /var/run/nginx-cache levels=1:2       
                   keys_zone=WORDPRESS:100m inactive=60m;
fastcgi_cache_key "$scheme$request_method$host$request_uri";

server {
    server_name example.com www.example.com;
    root /var/www/example.com/htdocs;
    index index.php;

    access_log /var/log/nginx/example.com.access.log;
    error_log  /var/log/nginx/example.com.error.log;

    set $skip_cache 0;

    # POST requests and URLs with a query string should always go to PHP
    if ($request_method = POST) {
        set $skip_cache 1;
    }   

    if ($query_string != "") {
        set $skip_cache 1;
    }   

    # Don't cache URIs containing the following segments
    if ($request_uri ~* "/wp-admin/|/xmlrpc.php|wp-.*.php|/feed/|index.php
                         |sitemap(_index)?.xml") {
        set $skip_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") {
        set $skip_cache 1;
    }

    location / {
        try_files $uri $uri/ /index.php?$args;
    }    

    location ~ \.php$ {
        try_files $uri /index.php;
        include fastcgi_params;
        fastcgi_pass unix:/var/run/php5-fpm.sock;
        fastcgi_cache_bypass $skip_cache;
        fastcgi_no_cache $skip_cache;
        fastcgi_cache WORDPRESS;
        fastcgi_cache_valid  60m;
    }

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

    location ~* ^.+\.(ogg|ogv|svg|svgz|eot|otf|woff|mp4|ttf|css|rss|atom|js|jpg|jpeg
                      |gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|ppt|tar|mid|midi
                      |wav|bmp|rtf)$ {

        access_log off;	
        log_not_found off;
        expires max;
    }

    location = /robots.txt {
        access_log off;
        log_not_found off;
    }

    location ~ /\. {
        deny  all; 
        access_log off;
        log_not_found off;
    }
}

[pothi]

Hello,

Thanks for your efforts to put together the whole configuration.

Here are my thoughts about NGINX's (FastCGI and Proxy) cache in general (not particular to your configuration). Ref: https://www.nginx.com/blog/nginx-caching-guide/

1. The fastcgi_cache_purge functionality is available only as part of commercial subscription. Ref: https://nginx.org/r/fastcgi_cache_purge
2. Caching is easy but purging is hard. We definitely need a plugin to purge the cache whenever we publish a new post or update an existing post. There are already a few plugins available in this regard. Each come with its own set of Nginx configuration and recommended settings that are questionable. So, it is easy if someone wants to use Nginx's builtin (proxy or fastcgi) cache by just following the recommended Nginx configuration from the particular plugin.
3. I'd recommend Varnish if someone wants to utilize server-side caching techniques, because caching and purging are free in Varnish (even though Varnish has commercial interests too). One would still need a plugin to send purge requests. Also, in Varnish, if is not evil. Actually, if can be utilized more effectively in Varnish. For example, we can whitelist purge requests from particular set of IPs easily.

Coming back to the above configuration... as per the official recommendation from Nginx, the only 100% safe things which may be done inside if in a location context are...

• return ...;
• rewrite ... last;

I will keep this feature request open for now. If there are enough interest in it in the future, we'll work on it to fine-tune it to...

• replace if statements that comes with set statement.
• limit purge requests to white-listed IPs.
• a plugin to send purge requests (this is likely easier, as we can fork an existing Varnish plugin or write a new plugin from scratch).

Thanks again,
Pothi.

[firestrife23]

Thank you for your constructive options. Not everyone will agree with you, it's good to offer choices, I've seen plenty of debates on which caches are the best... it's same as arguing over vim vs emacs for years which is pointless. There's a plugin for nginx cache, see here https://wordpress.org/plugins/nginx-helper/