How to Display Wordpress Sidebar on Other (Non WP) Sites

Before we can write our function, we need to understand exactly what we’re trying to do. Our goal is to cache our sidebar to a text file and update that cache whenever we publish a post, change our theme or make changes to the sidebar widgets. Since we’re planning on using our cache to display the sidebar on a different application, we need to be able to easily delete the cache without any ill-effects (we don’t want our sidebar broken at any time).

To accomplish this efficiently, we’ll also create a log of our cached files and use that to determine whether the cache should be cleared. If so, the actual cache file will be overwritten the next time someone visits the WordPress site, ensuring a proper sidebar is always rendered on both applications.