Retrieve taxonomies attached to the attachment.

Signature

get_attachment_taxonomies( $attachment )
attachment
 (int|array|object) Attachment ID, Attachment data array, or Attachment data object.

Return

(array) Empty array on failure. List of taxonomies on success.

Source

function get_attachment_taxonomies($attachment) {
	if ( is_int( $attachment ) )
		$attachment = get_post($attachment);
	else if ( is_array($attachment) )
		$attachment = (object) $attachment;

	if ( ! is_object($attachment) )
		return array();

	$filename = basename($attachment->guid);

	$objects = array('attachment');

	if ( false !== strpos($filename, '.') )
		$objects[] = 'attachment:' . substr($filename, strrpos($filename, '.') + 1);
	if ( !empty($attachment->post_mime_type) ) {
		$objects[] = 'attachment:' . $attachment->post_mime_type;
		if ( false !== strpos($attachment->post_mime_type, '/') )
			foreach ( explode('/', $attachment->post_mime_type) as $token )
				if ( !empty($token) )
					$objects[] = "attachment:$token";
	}

	$taxonomies = array();
	foreach ( $objects as $object )
		if ( $taxes = get_object_taxonomies($object) )
			$taxonomies = array_merge($taxonomies, $taxes);

	return array_unique($taxonomies);
}
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