[attachment_category] param behavior

I omitted an extra parameter and it simplified the example too much. The full problematic syntax should look like this:

[mla_gallery attachment_category="jewelboxes,c-indian-east" tax_operator=AND tax_include_children=true]

These don’t work:
– “jewelboxes” has no attached media, but its children do (longbox, squarebox), it still returns nothing.
– “jewelboxes” has all the media of its children attached, but also has the tax_include_children=true parameter, it still returns nothing because of this.

The only way to make it work as expected is attaching media to the parent and excluding its children:

[mla_gallery attachment_category="jewelboxes,c-indian-east" tax_operator=AND tax_include_children=false]

Thank you very much for the advanced query example usage! It was eye-opening, and helped improve my code to generalize the support for term_group and other tweaks.

However, a quite unexpected issue happened.

As I’ve multiple paginations in a single page, I’ve switched to the mla_gallery_raw_attributes hook instead of mla_gallery_attributes, as mentioned in this post. The “raw” hook and tax_query together though make the situation “catastrophic”, hanging the server and filling error_log with hundred of thousands of repeating PHP notices about these 4 lines:

[20-Aug-2017 06:01:50 UTC] PHP Warning:  strpos() expects parameter 1 to be string, array given in D:\domains\wp.mydomain.com\wp-content\plugins\media-library-assistant\includes\class-mla-data.php on line 1254
[20-Aug-2017 06:01:50 UTC] PHP Warning:  strpos() expects parameter 1 to be string, array given in D:\domains\wp.mydomain.com\wp-content\plugins\media-library-assistant\includes\class-mla-data.php on line 1258
[20-Aug-2017 06:01:50 UTC] PHP Warning:  strpos() expects parameter 1 to be string, array given in D:\domains\wp.mydomain.com\wp-content\plugins\media-library-assistant\includes\class-mla-data.php on line 1265
[20-Aug-2017 06:01:50 UTC] PHP Warning:  substr() expects parameter 1 to be string, array given in D:\domains\wp.mydomain.com\wp-content\plugins\media-library-assistant\includes\class-mla-data.php on line 1280

Using the mla_gallery_attributes hook instead things go back to normal, and tax_query seems working, but pagination with a custom mla_page_parameter doesn’t paginate (i.e. repeats the first page over and over — the reason I switched to the ‘raw’ version of the hook that fixed this).

Here’s my code example:

/**
 * Manage custom MLA syntax to display galleries in lightbox pop-ups
 * https://wordpress.org/support/topic/group-of-wc-product/
 * Example Usage:
 * [mla_gallery attachment_category=a3-print my_term_group=true]
 */
add_filter( 'mla_gallery_attributes', 'ew_gallery_attributes', 10, 1 );
function ew_gallery_attributes( $attr ) {
    if( $attr['my_term_group'] === 'true' && $attr['attachment_category'] ) {
        // Build a complex query: attachment_category term AND term_group terms associated with product
        $attr['tax_query'] = ew_tax_query( $attr['attachment_category'] );
        // Differentiate between multiple paginations
        $attr['mla_page_parameter'] = 'mla_paginate_'.$attr['attachment_category']; 
        // attributes not needed anymore should get disposed
        unset( $attr['attachment_category'] );
        unset( $attr['my_term_group'] );
    } 
	return $attr;
}
/**
 * Query Builder. Properly handle search in attachment_category hierarchies  
 * Example: ( jewel-boxes OR long-box OR square-box ) AND (c-indian-east OR c-mermaids)
 * https://wordpress.org/support/topic/attachment_category-param-behavior/#post-9423956
 */
function ew_tax_query( $term ) {
    $tax_query = array(
        'relation'              => 'AND',
        array(
            'taxonomy'          => 'attachment_category',
            'field'             => 'slug',
            'terms'             => array( $term ),
            'operator'          => 'IN',
            'include_children'  => true
            ),
        array(
            'taxonomy'          => 'attachment_category',
            'field'             => 'slug',
            'terms'             => array('c-indian-east','c-mermaids'),
            'operator'          => 'IN',
            'include_children'  => false
            )
        );
    return $tax_query;
}