Wordpress register_rest_route not working in WC

I am fairly new to Wordpress/WooCommerce and I'm struggling to get a custom rest api endpoint registered. The following gives me a 404 when I try the endpoint :

class WC_FastSpring_Fulfillment_Integration extends WC_Integration {

    public function __construct() {
        $this->id = 'av-wc-fastspring';
        $this->method_title = '';
        $this->method_description = '';
    
        // Method with all the options fields
        $this->init_form_fields();
    
        // Load the settings.
        $this->init_settings();
        

        // This action hook saves the settings
        add_action( 'woocommerce_update_options_integration_' .  $this->id, array( $this, 'process_admin_options' ) );

        $namespace = 'test';
        $endpoint = '/fs-fulfill-order';
        add_action( 'rest_api_init', function () {
            $logger = wc_get_logger();
            $logger->debug("Registered API Endpoint");
            register_rest_route( $namespace, $endpoint, array(
                'methods' => 'GET',
                'callback' => array($this, 'fulfill_fastspring_order'),
                'permission_callback' => function() {
                    return true;
                }
            ) );
        } );
    }

    public function fulfill_fastspring_order() {
        global $woocommerce;
        $logger = wc_get_logger();
    
        $logger->debug("Received request to fullfill FastSpring order via Rest API.");
        return new WP_REST_Response('Damn !');
    }

    ...
}

It does work if I register outside of the class, but not inside ! Any ideas ? I do see the debug log I've added in the WooCommerce log though, so that add_action does seem to be triggered.

Thanks !

CodePudding user response：

I have corrected your code and split code into functions and now it is working

/**
*  Request URL: http://127.0.0.1/wordpress/wp-json/test/fs-fulfill-order
*/
class WC_FastSpring_Fulfillment_Integration extends WC_Integration{
  
  function __construct(){
    add_action( 'rest_api_init', array($this, 'rest_api_rest_init_fun'));
  }

  public function rest_api_rest_init_fun(){

    $namespace = 'test';
    $endpoint = '/fs-fulfill-order';
    register_rest_route( $namespace, $endpoint, array(
        'methods' => 'GET',
        'callback' => array($this, 'fulfill_fastspring_order'),
        'permission_callback' => function() {
            return true;
        }
    ));

  }

  public function fulfill_fastspring_order() {
      global $woocommerce;
      $logger = wc_get_logger();
      $logger->debug("Received request to fullfill FastSpring order via Rest API.");
      return new WP_REST_Response('Damn !');
  }

}

//call class
new WC_FastSpring_Fulfillment_Integration;

Screenshot: https://prnt.sc/217fait