node.js - mongoose obtains user information through UserId and cannot save it to the object

Question

const ep = new eventproxy();
  ep.fail(next);

  EveryDay.getRankByTodayDate(TodayDate, ep.done('ranks'));

  ep.all('ranks', function(ranks){
    ranks.forEach(function(rank){
      User.getUserById(rank.userId, ep.done(function(user){
        rank.nickName = user.nickName; //这里不生效
        console.log(rank,rank.nickName); rank.nickName 有值，但是打印出的rank没有nickName 属性
        ep.emit('user');
      }))
    });

rank.nickName = user.nickName;

Why does assigning a value directly like this not take effect? How should we save the queried user nickname into the data object?

Answer 1

The reason is @nightclub小新新’s answer.

Currently, I use this method to deal with:

 EveryDay.find({TodayDate}).lean()
    .exec((err, ranks) => {
    ...
    }
    )

I will add more when I find better answers later.

Answer 2

You will know by debugging the data structure of the query results of mongoose. Only the data defined by your schema can be operated on mongoose data. Only the get/set methods are available. Other undefined attributes cannot be operated unless they are saved to _doc. in or converted into a normal object