At work, one of the more interesting customizations we have on WordPress.com for our VIP clients is a dashboard that contains custom widgets. One of them is a page generation graph that shows the average page generation time for their site compared to all others. That way they can judge their code performance against a [...]
Quick Tip: DreamHost cron and WP-CLI
If you're hosting your WordPress website on DreamHost, and use their cron system to offload your WordPress faux-cron for better reliability, be careful of what version of PHP you have in your code. I recently had an issue where my cron events weren't firing, and after enabling email output, I ended up with something like this PHP [...]
Blogging Anonymously
An interesting problem I came across recently was how to set up a WordPress blog with an anonymous user. Now, a simple way would be to create a brand new user with fake information, but that's too easy. After looking for some prior art, I found the Anonymizer plugin in the WordPress.org plugin repository. Unfortunately, it's [...]
Logging Failed Redirects
WordPress has a built-in function called wp_safe_redirect(). This allows you to create redirects in code, but only to whitelisted domains (via the allowed_redirect_hosts filter). The downside to this is that you have to remember to whitelist the domains. It's easy to forget if you're doing a lot of redirects, for instance with the WPCOM Legacy Redirector [...]
Purging All The Caches!
One of the best ways to ensure that a WordPress site--well any site really--stays performant and not broken is by leveraging caching. WordPress by default doesn't do much caching other than some in-memory caching of objects, and the odd database caching via the Transients API. This site currently has three layers of caching: PHP OPcache [...]
Quick Tip: Viewing Headers With Curl
Something that I do often at work is to check HTTP headers for random things such as redirects, cache headers, proxies, ssl, etc. A common way this is done is by using the -I (--header) switch: $ curl -I http://example.com/ HTTP/1.1 200 OK Content-Encoding: gzip Accept-Ranges: bytes Cache-Control: max-age=604800 Content-Type: text/html Date: Wed, 27 Jun 2018 [...]
Disabling WordPress Faux Cron
The WordPress WP-Cron system is a decently okay faux cron system, but it has its problems, such as running on frontend requests and not running if no requests are coming through. WP-Cron works by: on every page load, a list of scheduled tasks is checked to see what needs to be run. Any tasks scheduled [...]
Quick Tip: Force Enable Auto-Updates in WordPress
I know that auto-updates are a bit of a (#wpdrama) touchy subject, but I believe in them. In an mu-plugin I enable all auto-updates like so: <?php // Turn on auto-updates for everything if ( ! defined( 'IS_PRESSABLE' ) || ! IS_PRESSABLE ) { add_filter( 'allow_major_auto_core_updates', '__return_true' ); add_filter( 'allow_minor_auto_core_updates', '__return_true' ); } add_filter( 'auto_update_core', '__return_true' [...]
Query Caching (and a little extra)
By default, WordPress does not cache WP_Query queries. Doing so can greatly improve performance. The way I do this is via the Advanced Post Cache plugin: https://github.com/Automattic/advanced-post-cache By running this plugin (hopefully as an mu-plugin) with a persistent object cache, WP_Query calls, along with get_post() calls (only if suppress_filters is false) will be cached. Bonus! Now that we're caching queries, [...]
Auto-enable WP_DEBUG with a cookie
One of the most important things to do when working on new themes, plugins, or debugging issues in WordPress is to turn on WP_DEBUG. According to the Codex: WP_DEBUG is a PHP constant (a permanent global variable) that can be used to trigger the "debug" mode throughout WordPress. It is assumed to be false by [...]