Theme logo metadata into template file

Question

I'm looking to pull all of the metadata (e.g. alt, width, height) from the theme logo, which is uploaded through Appearance -> Customization into my theme template file. This is what I currently have, but it's not working:

$custom_logo_id = get_theme_mod('custom_logo');
if ($custom_logo_id) {
    $image = wp_get_attachment_image_src($custom_logo_id, 'full');
    $meta = wp_get_attachment_metadata($custom_logo_id);
    echo '<img src="' . $image[0] . '" alt="' . $meta['alt'] . ' width="' . $meta['width'] . '" height="' . $meta['height'] . '">';
} else {
    echo bloginfo('name');
}

Answer 1

Ends up that "alt" is not stored in wp_get_attachment_metadata so I pulled it from the post meta:

$custom_logo_id = get_theme_mod('custom_logo');
if ($custom_logo_id) {
    $image = wp_get_attachment_image_src($custom_logo_id, 'full');
    $meta = wp_get_attachment_metadata($custom_logo_id);
    **$alt_text = get_post_meta($custom_logo_id, '_wp_attachment_image_alt', true);**
    echo '<img src="' . $image[0] . '" alt="' . $alt_text . '" width="' . $meta['width'] . '" height="' . $meta['height'] . '">';
} else {
    echo bloginfo('name');
}

Answer 2

As you can see from the description of wp_get_attachment_metadata there's no alt field stored in that location. The easiest way out would be to just use the title-field for the alt.

Otherwise you can retrieve the alt-field using get_post_meta. More explanation here.