code: function validateContainer (container) {
    var err;
    if (!container || container.error) {
      err = Boom.create(504, 'instance is down (no container)', container.error);
    }
    else if (container.inspect.error) {
      err = Boom.create(503, 'instance inspect failed (try again)', container.inspect.error);
    }
  
    return err;
  }
docs: validate container existence
  @param  {Object} container instance.attrs.container - instance container json
  @return {Error}  err       returns err only if container does not exist