gillesgoetsch

<?php

/**
 * Plugin Name: Filter Orders by currency
 * Description: Adds the ability to filter orders by currency.
 * Author: Gilles Goetsch
 * Author URI: https://gillesgoetsch.ch/
 * Version: 1.0.0
 * Text Domain: wc-filter-orders
 * Reference: http://www.skyverge.com/product/woocommerce-filter-orders/

gillesgoetsch

/**
 * WC API v3 - add functionality to filter by order_currency
 * example request: /wp-json/wc/v3/orders?status=processing&per_page=-1&currency=EUR
 */

add_filter( 'woocommerce_rest_orders_prepare_object_query', 'theme_woocommerce_rest_orders_prepare_object_query', 10, 2 );
function theme_woocommerce_rest_orders_prepare_object_query( $args, $request ){

    $args['meta_query'][] = array(
        'key'   => '_order_currency',