/wp/v2/pattern-directory/patterns endpoint: slug parameter has no effect on the response

[antonvlasenko]

Steps to reproduce the bug:

1. Install ​this plugin to allow basic authorization for REST API requests.
2. Activate the plugin.
3. Send a GET request to your WordPress instance, e.g.:

curl --user username:user_password "http://your.wordpress.instance/wp-json/wp/v2/pattern-directory/patterns?slug%5B0%5D=visual-navigation-with-rainbow-gradient"

Replace

username:user_password

with the actual credentials.
Replace

http://your.wordpress.instance

with the actual URL of your instance.

3. Note the response. It should contain at least 1 pattern.
4. Send a GET request again, but this time replace

   visual-navigation-with-rainbow-gradient
   

with some non-existent pattern. E.g.:

curl --user username:user_password "http://your.wordpress.instance/wp-json/wp/v2/pattern-directory/patterns?slug%5B0%5D=non-existent-pattern"

Expected result:
The endpoint should return an empty response.
Actual result:
The endpoint will return the previous response. slug parameter has no effect on the response.

Trac ticket: https://core.trac.wordpress.org/ticket/55617

[spacedmonkey]

I haven't looked to deeply into this, but I noticed that slug was query params in get_collection_params. We could fix that as part of this solution.

[antonvlasenko]

Replying to spacedmonkey:

I haven't looked to deeply into this, but I noticed that slug was query params in get_collection_params. We could fix that as part of this solution.

I agree, it would be nice to fix it.
Fixed it in ​https://github.com/WordPress/wordpress-develop/pull/2625/commits/b1598ab4191ac31cb8f3e019163f7c384a22ad5a

[antonvlasenko]

I'm not sure why needs-patch and needs-unit-tests added tags were added, because there is a patch and unit tests.
I've fixed all the feedback and failed unit tests.

[hellofromTonya]

Updating the keywords.

[antonvlasenko]

I've marked this bug as major because WordPress sends a request to the wp/v2/pattern-directory/patterns endpoint when a user navigates the Site Editor page (/wp-admin/site-editor.php).
It may happen that the list of available ​patterns supported by the current theme will be incorrect because the wrong response from the wp/v2/pattern-directory/patterns endpoint will get cached (for 1 hour).
I haven't been able to spot any issues on the front end, but the bug is reproducible and can have unpredictable consequences.
This bug was intoruced in the recent changeset.
In my opinion, it should be fixed ASAP.
FYI: @spacedmonkey

There are a number of changes required here.

Thank you for the review, @spacedmonkey!
I've replied to all code review comments.
I'd appreciate the second round of the review.

@anton-vlasenko I working on cleaning up the ​6.0 Project Board. Are we waiting on anything else for this PR?

@anton-vlasenko I'm working on cleaning up the ​6.0 Project Board. Are we waiting on anything else for this PR?

@ndiego
From a technical point of view, this PR is ready to be merged.
2 core commiters have approved it.

I don't know if there are any problems from an organizational point of view.
I'd be grateful if you could please merge it (I don't know if you have the permission to merge to Beta 4).
Thank you.

cc @peterwilsoncc

[hellofromTonya]

As this bug was introduced during the 6.0 beta cycle in [53218] and it has approval, I'll do the review, test, and if ready, commit before Beta 4 release cycle starts.

[hellofromTonya]

Prepping for commit.

[hellofromTonya]

In 53333:

REST API: Fixes /wp/v2/pattern-directory/patterns endpoint response for slug parameter.

[53218] introduced a bug of a wrong response from the wp/v2/pattern-directory/patterns endpoint with a slug parameter. As the response is cached, it can result in an incorrect list of available patterns supported by the current theme.

This commit resolves by:

• Limiting the slug to an array in the query parameters.
• When set, parsing and sorting the slug(s) and then serializing the sorted query args as part of the hashed transient keys.

Props antonvlasenko, timothyblynjacobs, spacedmonkey, costdev, hellofromTonya.

Follow-up to [53218], [53152], [51208].
Fixes #55617.

Committed via changeset https://core.trac.wordpress.org/changeset/53333.