Drag and drop uploading should respect multisite max upload size

[danielbachhuber]

Issue Overview

Drag and drop upload doesn't respect the max upload size option in WordPress multisite.

For reference, here's an example of the error in the media library:

In Gutenberg, I'm permitted to upload the same image without error.

Steps to Reproduce (for bugs)

In the network admin, configure "Max upload file size" to be a small-ish number:

Then, try uploading an image of a larger size into Gutenberg.

Expected Behavior

My expected error is to see some equivalent error in the Gutenberg editor. This validation should initially be handled client-side as Plupload, but also handled in the REST API (https://core.trac.wordpress.org/ticket/43751).

In resolving this issue, we'll need to also make sure Gutenberg respects the "Site upload space" option.

The two sitemeta options are fileupload_maxk and blog_upload_space:

[jorgefilipecosta]

I think this PR #4203 will handle the issue.

[danielbachhuber]

@jorgefilipecosta The PR also needs to respect blog_upload_space on multisite. It doesn't appear to include that.

[danielbachhuber]

I've updated the Core Trac ticket with a patch I like: https://core.trac.wordpress.org/ticket/43751#comment:3

We can close this issue when a patch for the Trac ticket lands in Core. At this point, I don't think it's worth backporting the change to Gutenberg.

[danielbachhuber]

🚢