Allow media file size to be set from metadata when viewing media modal

[polevaultweb]

When viewing an attachment in the edit post screen, the file size is either calculated from the actual file, or taken from 'filesize' if set, from wp_get_attachment_metadata(). This alternative to using filesize( $file ); is helpful for image plugins that store the file somewhere else, i.e. it doesn't exist locally.

However, when you view the media in the modal, the file size is only calculated using the local file.

[polevaultweb]

This patch unifies the implementation between

/wp-admin/includes/media.php line 2823

and

/wp-includes/media.php line 2765

[wonderboymusic]

In 34258:

Media: In wp_prepare_attachment_for_js(), don't call file_exists() and filesize() to retrieve $bytes if the data is already present in $meta. This is how the same code in attachment_submitbox_metadata() already works.

Props polevaultweb.
Fixes #33214.

[drywallbmb]

This is great, but is there anywhere in core where the filesize is actually being stored in the metadata? From what I can tell, these queries are always going to turn up nothing and wind up having to actually look at the filesystem to get the file size. In which case, why add this overhead of asking the DB/metadata first?

[drywallbmb]

Upon further review, it looks as though WP does populate filesize, but only for media types that get processed by the ID3 library. Is that right? Seems odd to do it for some filetypes and not others.

[SergeyBiryukov]

Replying to drywallbmb:

Upon further review, it looks as though WP does populate filesize, but only for media types that get processed by the ID3 library. Is that right? Seems odd to do it for some filetypes and not others.

That indeed seems to be the case. Related: comment:8:ticket:47459.