Invalid argument supplied for foreach() in /wp-includes/embed-template.php on line 54

[MarkRH]

I believe I uncovered a bug. Support thread: ​https://wordpress.org/support/topic/invalid-argument-foreach-embed-templatephp-on-line-54?replies=7

In my media settings I have thumbnails set to 200x200, medium 300x300, large 1024x1024.

Some of my older posts have featured images that are smaller than 200x200. As such, these additional sizes were not created. When looking at the /embed/ variant of said post, this warning is generated in the PHP error_log file:

Invalid argument supplied for foreach() in /wp-includes/embed-template.php on line 54

I added the following code to echo the $meta variable:

<?php
$meta = wp_get_attachment_metadata( $thumbnail_id );
         if ($_SERVER['REMOTE_ADDR'] == HOME_IP) {
            print_r($meta);
         }
         if ( is_array( $meta ) ) {
            foreach ( $meta['sizes'] as $size => $data ) {
               if ( $data['width'] / $data['height'] > $aspect_ratio ) {
                  $aspect_ratio = $data['width'] / $data['height'];
                  $measurements = array( $data['width'], $data['height'] );
                  $image_size   = $size;
               }
            }
         }

Here's what a post with the issue outputs:

Array
(
    [width] => 105
    [height] => 107
    [hwstring_small] => height='96' width='94'
    [file] => 2011/03/stpatricks_clover.jpg
    [image_meta] => Array
        (
            [aperture] => 0
            [credit] =>
            [camera] =>
            [caption] =>
            [created_timestamp] => 0
            [copyright] =>
            [focal_length] => 0
            [iso] => 0
            [shutter_speed] => 0
            [title] =>
        )

)

As you can see, there is no [sizes] section which causes the warning on the foreach line that uses it. Posts which have no images associated with them or image larger than 200x200 do not have the issue.

[swissspidy]

Good catch!

I just uploaded a patch which should fix this for now. The goal is to simplify the embed template in 4.5, see #34561 for more information.

[dd32]

Could this entire check be if ( ! empty( $meta['sizes'] ) )? Is there a case where meta might be a non-false non-array or sizes contain anything other than an array?

[swissspidy]

Replying to dd32:

Could this entire check be if ( ! empty( $meta['sizes'] ) )? Is there a case where meta might be a non-false non-array or sizes contain anything other than an array?

Yeah that would work too, from what I remember & tested now.

[swissspidy]

New patch using if ( ! empty( $meta['sizes'] ) )

[swissspidy]

In 36123:

Embeds: Change attachment metadata condition to prevent a warning in the embeds template.

Fixes #35237.

[dd32]

In 36147:

Embeds: Change attachment metadata condition to prevent a warning in the embeds template.

Merges [36123] to the 4.4 branch.
Fixes #35237.

[swissspidy]

In 37452:

Embeds: Change attachment metadata condition to prevent a warning in the embeds template.

See #35237.
Fixes #36838 for trunk.

[ocean90]

In 37455:

Embeds: Change attachment metadata condition to prevent a warning in the embeds template.

Merge of [37452] to the 4.5 branch.

Props swissspidy.
See #35237.
Fixes #36838.