Reply To: Filter products/categories/ by ACF field

• Jelmertje

• January 7, 2022 at 5:47 am

I have experimented a bit and I can confirm the following works for regular categories:

$GLOBALS['my_query_filters'] = array(
	'field_1' => 'id_category_mercator',
);

add_action('pre_get_terms', 'my_pre_get_terms', 10, 1);
function my_pre_get_terms( $query ) {
    
	// bail early if is in admin
	if( is_admin() ) return;
	
	// bail early if not main query
	// - allows custom code / plugins to continue working
	//if( !$query->is_main_query() ) return;

	// get meta query
	$meta_query = $query->meta_query;
	
	// loop over filters
	foreach( $GLOBALS['my_query_filters'] as $key => $name ) {
		
		// continue if not found in url
		if( empty($_GET[ $name ]) ) {
			continue;
		}
		
		// get the value for this filter
		// eg: https://mywebsite/wp-json/wc/v3/products/category?id_category_mercator=merca1
		$value = explode(',', $_GET[ $name ]);
		
		
		// append meta query
    	$meta_query->queries[] = array(
            'key'		=> $name,
            'value'		=> $value,
            'compare'	=> 'IN',
        );
        
	} 
	
	// update meta query
	$query->meta_query = $meta_query;
}

You might want to figure something out to replace the commented out line of code:
//if( !$query->is_main_query() ) return;

But I don’t know what other functionality your project has that could cause/suffer conflicts.