Fetch all attachments when opening a gallery in the Media Library

[danielbachhuber]

Description

Switches wp.media.query to use posts_per_page=-1 and fetch all attachments when opening a gallery in the Media Library.

See #10873 (comment)

How has this been tested?

1. Create a Gallery Block and click Edit:

2. Inspect the Network Tab and verify that posts_per_page=-1 was used in the request and that the request was successful:

[adamsilverstein]

Why are we using unbounded queues vs pagination?

[danielbachhuber]

Why are we using unbounded queues vs pagination?

Isn't this what core currently does for wp.media.query ?

[joemcgill]

I just double checked, and can confirm that in the classic editor we are including posts_per_page=-1 when the query-attachments action is called to get data for a gallery. In this case, it seems to make sense, because we are pairing that with a post__in value containing an array of all image IDs in the gallery.

1. I don't see anything in this PR that limits this to only apply to galleries, but I think it's a reasonable expectation that we would fetch all of the attachment data needed by any block that is saving a set of attachment IDs.
2. wp.media.query actually uses perPage as the property instead of per_page, which gets mapped to posts_per_page here. So good catch that it was wrong. Changing it to posts_per_page directly should work fine, however.

[joemcgill]

As noted in my comment, wp.media.query() normally uses perPage instead of posts_per_page, but either should work and I slightly prefer the fact that this is consistent with the WP_Query args that are more familiar.

TL;DR – LGTM.