Heads-up: breaking cache callback change affected the MainWP integration

[sisaacrussell]

Hi @otarhe,

(I use Pressable Cache Management with MainWP Cache Control and ran into a compatibility issue I wanted to flag. I’m a MainWP user contributing a fix, not a member of the MainWP team.)

MainWP was calling flush_pressable_cache_callback(), which was replaced in October 2025 with pcm_abar_flush_object_callback(). The changelog didn’t mention this callback change or warn about its compatibility impact. With the old function gone, MainWP skipped the purge but still reported success (a separate issue on its own). The fix I’ve submitted to MainWP now calls wp_cache_flush(), batcache_clear_cache() when available, and Edge_Cache_Plugin::get_instance()->purge_domain_now() when Edge Cache is enabled. It checks the results and fires the pcm_after_object_cache_flush and pcm_after_edge_cache_purge hooks after their respective operations succeed.

MainWP issue #502
MainWP PR #503

I recognize the original function was an AJAX callback and may never have been intended as a supported integration API. People are using and extending this plugin, though, so changes like this can affect workflows beyond its own settings page and toolbar.

For future releases, could you flag potentially breaking changes in the changelog? Just a brief note that functions or hooks have been renamed or removed would help people maintaining integrations know when to review and test their code.

Thanks for the recent fixes and continued work on the plugin!

[otarhe]

Hi @sisaacrussell,

Thank you for the detailed report, and for going the extra step of fixing this on the MainWP side and linking the PR, that's genuinely appreciated.

You're right on every point. flush_pressable_cache_callback() was renamed in October 2025 and the changelog said nothing about it. That was a miss on our part, and the fact that it was an AJAX handler rather than an intended integration point doesn't change that people were relying on it.

Going forward, every release's changelog will include a dedicated Breaking changes / Deprecations section listing any functions, hooks, actions, or files that were renamed or removed, so anyone maintaining an integration knows exactly when to review and test. We're starting with the upcoming release.

One item from that upcoming release is worth flagging to you directly: the admin bar AJAX callbacks (pcm_abar_flush_object_callback, pcm_abar_purge_edge_callback, and the combined flush) now require a nonce, so calling them directly will fail. Your PR already avoids them, which is the right call, just noting it in case any older integration code is still around.

We're also looking at providing a properly supported function/hook for triggering purges, so integrations don't need to depend on option names or internal hooks. I'll update this issue when there's something concrete.

Thanks again for the thoughtful write up and for the kind words about the recent fixes.