post.php AJAX request not being called when publishing post

I am using the transition_post_status to process a post being published. I was getting inconsistent behaviour between two installations of WordPress, and I have tracked this down to the AJAX calls being made from the post compose page itself.

These are the requests being made when I transition a post from a draft to published on my two installations:

As you can see, the AJAX call to post.php is not being made in the second example. It turns out that the global $post object is in a different state inside transition_post_status hook when being called via post.php, which is why my code only works on the first installation.

What I need to understand is why I have 2 installations of WordPress that are seemingly doing different things when publishing a post.

Both installations are running 5.7.2, and are stock aside from the 1 plugin that I am working on, which is the same on both installations.

Can anyone shed any light on why two different installations are triggering different AJAX calls when publishing a post?

Topic admin hooks publish Wordpress

Category Web

1
answered at

It turns out that the calls to /wp-admin/post.php are due to there being custom meta boxes on the post compose page. The initial XHR request is to the WP API to save the post, but then additional XHR calls are made to process the meta boxes. This then re-saves the post, and calls the transition_post_status hook again.

When the API first saves the post, the status is going from draft to publish, and on the secondary calls, if they run, it is going from publish to publish - that in itself makes sense.

My specific problem was that I was calling some code that required $post to be globalised, which was only the case in the second XHR call, leading to inconsistent behaviour when the hook which called that code was being run twice - one when $post was globalised and one when it was not.

About

Geeks Mental is a community that publishes articles and tutorials about Web, Android, Data Science, new techniques and Linux security.