I use prism to handle all of the code highlighting for this site, which works great apart from one thing – it expects the class on a <pre> element to be in the format language-<name> rather than just <name>.

As I write all my content in Markdown, I need to add a wp_insert_post_data handler to make this change as the HTML is being saved to the DB.

function filter_handler( $data , $postarr ) {
   // Modify data as required
}

add_filter( 'wp_insert_post_data', 'filter_handler', '99', 2 );

I didn’t want to go back and trigger an update of every single post (there’s quite a few on here now), so I worked out a way to update all published post states to published. This doesn’t change the content but it does re-trigger the wp_insert_post_data filter.

So I present to you, my one liner (using WP CLI) that triggers a rebuild of every page:

for i in `wp post list --fields=ID,post_status | grep publish | awk '{print $1}'`; do wp post update $i --post-status=publish; done

Michael Heap

Michael is a polyglot software engineer, committed to reducing complexity in systems and making them more predictable. Working with a variety of languages and tools, he shares his technical expertise to audiences all around the world at user groups and conferences. You can follow @mheap on Twitter