Jetpack: Core Image Migration: post type jetpack_migration is not registered

[charlestonsoftware]

Steps to reproduce the issue

Turn on DEBUG_LOG (define true).

Create a post.

Save as draft.

What I expected

No warnings or notices.

What happened instead

PHP notices about post types not being registered.

PHP Notice: map_meta_cap was called incorrectly. The post type jetpack_migration is not registered, so it may no
t be reliable to check the capability "edit_post" against a post of that type. Please see Debugg
ing in WordPress for more information. (This message was added in version 4.4.0.) in /var/www/hmlive/wp-includes/functions.php on line 4139

Triggered by 'widgets_init' action call via
add_action( 'widgets_init', 'jetpack_migrate_image_widget' );
in image-widget.php.

This new module was added in JetPack 4.9 according to the phpDoc
header and I did recently upgrade the JP on this site from < 4.9 to
5.1.

The problem , at least from what I can tell, is the
'jetpack_migration' post type is never registered. I don't see how
this piece of code could have ever worked as intended; at least not in
the production form.

Maybe a branch was no merged properly before
release?

The "nice" way to manage this would be to ensure the jetpack_migration post type is registered BEFORE calling wp_insert_post() and maybe do something nicer than generate a notice/warning.

Since this function does not appear that it will actually do anything when jetpack_store_legacy_image_widget_options() is called some investigation may want to occur as to why this seems to be called on every post save if a site has JetPack 4.9+ installed. Seems like a lot of extra overhead. Maybe it is the wonderful theme I am using on the HereMusic.Live site. I've not tested this on the half-dozen other sites I am running JetPack on.

If you need more info please let me know.

[LeoChalvin]

I have just started encountering this issue on one of my sites that uses JetPack today. Is there any chance you have found a fix to this problem? I'm now unable to save drafts of my posts.

[eliorivero]

Hi, sorry to know that you're having this issue. For any other checking this issue, I've reproduced this after deleting what indicated that my widget migration had been performed with:
wp jetpack options delete image_widget_migration

The wp_insert_post call actually works without needing a CPT to be registered before. However, in your and my case it seems other plugins were performing calls such that map_meta_cap was called. I've opened this PR that fixes this issue.

The easiest way to temporarily patch this is to set WP_DEBUG to false, however, if you want to have it turned on, so here are some alternatives:

• you can solve this if you're using WP CLI with
  wp jetpack options update image_widget_migration true

• if you're not using WP CLI, you can edit wp-content/plugins/jetpack/jetpack.php and paste this at the end:
  Jetpack_Options::update_option( 'image_widget_migration', true );
  and load Jetpack settings screen. Then delete the line since it's no longer needed.