Get a list of currently available shipping services in woocommerce

function-woo-get-shippings.php

if ( ! function_exists( "get_shippings" ) ) {
/**
 * Get a list of currently available shipping services.
 * https://gist.github.com/MrSwed/dce4b3dd462eb18d3e7a198d8dfd4321
 * 
 * @param mixed $filter instance_id if number, id if string, call it if it is function or array of fields for filter
 *
 * @return array
*/

	function get_shippings( $filter = array() ) {
		if ( ! class_exists( 'WC_Shipping_Zones' ) ) {
			return [];
		}
		$key   = 'WC_Shipping_Zones::get_zones()';
		$zones = wp_cache_get( $key, __CLASS__ );
		if ( $zones === false ) {
			$zones = WC_Shipping_Zones::get_zones();
			wp_cache_set( $key, $zones, __CLASS__ );
		}
		$shippings = array_reduce( $zones, function ( $r, $i ) use ( $filter ) {
			$methods = $i["shipping_methods"];
			if ( ! empty( $filter ) ) {
				if ( is_callable( $filter ) ) {
					$methods = array_filter( $methods, $filter );
				} else if ( is_numeric( $filter ) ) {
					$filter = array( "instance_id" => $filter );
				} else if ( is_string( $filter ) ) {
					$filter = array( "id" => $filter );
				}

				if ( is_array( $filter ) ) {
					$methods = array_filter( $methods, function ( $method ) use ( $filter ) {
						foreach ( $filter as $key => $key_arg ) {
							if ( ! isset( $method->$key )
							     or ( ( is_string( $key_arg ) or is_numeric( $key_arg ) ) and $method->$key !== $key_arg )
							     or ( ( is_array( $key_arg ) and ! in_array( $method->$key, $key_arg ) ) ) ) {
								return false;
							}
						}

						return true;
					} );
				}
			}

			return $r + array_combine(
							array_column( $methods, "instance_id" ),
							array_column( $methods, "title" ) );
		}, array() );

		return $shippings;
	}
}