woocommerce POS pos only meta_query not working with display shop page as categories

Question

I am trying to remove items from my shop that either have 0 stock or are marked to be POS only but for some reason only the 0 stock part works.

Here is my code. What am I doing wrong?

/****
Functions to remove items from store that have 0 stock
*****/
add_action( 'pre_get_posts', 'custom_pre_get_posts_query' );

function custom_pre_get_posts_query( $q ) {
    if ( ! $q->is_main_query() ) return;
    if ( ! $q->is_post_type_archive() ) return;
    if ( ! is_admin() ) {
        $meta_query = $q->get( 'meta_query' );
        $meta_query[] = array(
            'key'       => '_pos_visibility',
            'value'     => 'pos_only',
            'compare'   => '!='
            );
        $meta_query[] = array(
            'key'       => '_stock_status',
            'value'     => 'outofstock',
            'compare'   => '!='
            );

        $q->set( 'meta_query', $meta_query);
    }
    $q->set('orderby', array('date' => 'DESC'));

    remove_action( 'pre_get_posts', 'custom_pre_get_posts_query' );

}

thanks Leo

Answer 1

OK I figured out a few things.

1. THis only seems to be a problem when using the WooCommerce->Settings->Products->Display Shop Page Display is not set to products. i.e it is set to either Categories or categories and products.

Here is the code I used to eventually solve it.

add_action( 'woocommerce_product_query', 'hss_shop_query', 10 , 2);
function hss_shop_query( $q, $that )
{
// $q->set( 'author', $vendor_id );
    if ( ! is_admin()  ) {
        $meta_query = $q->get( 'meta_query' );

        if (!is_array($meta_query)){
            $meta_query = array();
        }
        $bHasPOSVisibility = false;
        $bHasOutOfStock = false;

        foreach ($meta_query as $mq) {
            if ($q->key == '_pos_visibility'){
                $bHasPOSVisibility = true;
            } else if ($q->key == '_stock_status'){
                $bHasOutOfStock = true;
            }
        }

        if (!$bHasPOSVisibility){
            $meta_query[] = array(
                'key'       => '_pos_visibility',
                'value'     => 'pos_only',
                'compare'   => '!='
                );
        }
        if (!$bHasOutOfStock){
            $meta_query[] = array(
                'key'       => '_stock_status',
                'value'     => 'outofstock',
                'compare'   => '!='
                );
        }
        $q->set( 'meta_query', $meta_query);
    }

//error_log("Query: ".var_export($q, true));
}

I do not know if I need to check if it already exists in the query or not but I put it in for future compatibility if they fix this issue.