无法更新saisjs水线中的布尔值

我正在进行一个基于SailsJS的项目,但现在我正在为一个文档编写更新过程,当我这样做时,得到了以下错误。

   {
      "code": "E_VALIDATION",
      "invalidAttributes": {
      "deleted": [
      {
        "rule": "boolean",
        "message": "\"boolean\" validation rule failed for input: 'true'\nSpecifically, it threw an error.  Details:\n undefined"
      }
    ]}
  }

在模型中,我

    deleted: {
        type: 'string',
        boolean: true
    }

在控制器中 //删除指定用户的操作 销毁:函数(req、res、next){

    // Logs actions details
    sails.log.info("Attempting to delete user ( " , req.param('id') , " ) from IP (IP adddress: " , req.ip , ")" );

    User.update({
        id: req.param('id')
    }, {
        deleted: true
    }).exec(function (err, user) {
        if (err) {

            // Handles the response containing some error
            ErrorHandler.response(err, req, res, next);
        }

        res.json(user);
    });
}