Drupal users, see Pantheon Modules for details on Drupal modules developed and maintained for the Pantheon workflow.
Pantheon maintains an optimized version of WordPress that includes WordPress Pantheon Cache plugin to control cache expiration.
Pantheon Must-Use Plugin is vital to the operation of your site on the platform and must not be removed from your codebase. Consider it a part of WordPress core, and do not hack it. The permanent activation of this plugin will not interfere with your local environment.
The functionality of this plugin is broken into two parts: Updates and Page Cache.
The Pantheon Updates plugin disables automatic updates of all plugins, themes, and WordPress core on Pantheon's Test and Live environments. We do this because it is unsafe to apply updates to production environments directly without first verifying updates on a development environment.
The Test and Live environment codebases also cannot be written to, preventing automatic updates from downloading files from WordPress.org. Any plugin or theme updates must be performed in a development environment then committed and deployed to the Test and Live environments. WordPress core updates must be applied to a development environment via our Git-based upstream core updates feature.
Check out the WordPress Dashboard section of Working in the WordPress Dashboard and Drupal Admin Interface for more information on managing plugins and themes across multiple environments.
The Pantheon Page Cache plugin facilitates communication between Pantheon's Edge Cache layer and WordPress, allowing you to clear the entire site cache and set the default cache age.
Navigate to your WordPress dashboard > click Settings > Pantheon Page Cache.
Click Clear Cache to clear the cache for the entire site (this does not clear Varnish or Redis).
Set Default Time to Live (TTL) to 600 seconds (optional).
Pantheon Advanced Page Cache automatically clears related pages from Pantheon's Edge when you update content. Without this plugin, pages expire from cache after 10 minutes (600 seconds) by default. This plugin allows fresh content to be immediately served to anonymous visitors.
Pantheon HUD provides situational awareness within the WordPress Dashboard when working on the Pantheon platform. It's helpful to have a reminder of which environment you're in, as well as quick access to links to get back to Pantheon's Dashboard, or to interface with your WordPress installation via the command line:
For installation details, see Configuring Environment Indicators.
If you see an error similar to the following in the error logs:
Fatal error: session_start(): Failed to initialize storage module: user (path: ) in …/code/wp-content/plugins/plugin-that-uses-sessions/example.php on line 2
The cause is likely a plugin in the mu-plugins directory that is instantiating a session prior to this plugin loading. To fix, deactivate the WP Native PHP Sessions plugin and instead load it via an mu-plugin that loads first.
For example, create an mu-plugin called
00.php and add a line in it to include the
WP Redis provides an alternative caching backend, taking work off the database, which is vital for scaling to a larger number of logged-in users. For more information, see Object Cache (formerly Redis) for Drupal or WordPress.