Mongoose Populate方法返回对象中的对象

我在用猫鼬填充-

let allLeaders = await DAOManager.populate(
        models.Users,
        { firstName: "Mayank" },
        {firstName: 1, lastName: 1, district: 1},
        { lean : true},
        { path: "userId", select: "county designation gender" }
    );

在用户模型中-

let Users = new schema({
userId: { type: schema.Types.ObjectId, ref: 'hubiloUsers' }})

输出:

 {
    "_id": "5a05799b936a8c707f0e022f",
    "userId": {
        "_id": "5a057915c31eb5601da9b75f",
        "designation": "CTO ",
        "gender": "male",
        "county": "India"
    },
    "firstName": "Mayank", 
    "lastName": "Sharma", 
    "district": "ABC"
    }

问题---在输出中我得到了userid对象。不管怎样,我可以从外部获取用户id输出数据吗?所以我可以将数据发送到视图或前端。非常感谢你提前