Question

我想使用deep-populate插件进行mongoose查询。我肯定没有经验，但是，我没有成功地深入了解某些事情。这是我的计划：

var mongoose = require('mongoose');

var MMAnswersSchema = new mongoose.Schema({
  user: { type: mongoose.Schema.Types.ObjectId, ref: 'User' },
  item: { type: mongoose.Schema.Types.ObjectId, ref: 'MMItem'},
  answer: [
    {
      skalaAnswer: Number,
      freitextAnswer: String,
      multipleChoiceAnswer: String,
      answered_at: { type: Date, required: true, default: Date.now }
    }
  ],
  last_answered: { type: Date, required: true, default: Date.now }
});

MMAnswersSchema.pre('save', function(next) {
  this.last_answered = Date.now;

  next();
});

mongoose.model('MMAnswer', MMAnswersSchema);

var deepPopulate = require('mongoose-deep-populate')(mongoose);
MMAnswersSchema.plugin(deepPopulate);

我是否将deepPopulate需要的东西放在正确的位置？

我现在用这条路来获取我的东西：

// Alle Antworten des aktuellen Users laden
    // Verwendet von der Historie
    .get('/mm-answers/:user_id/get-all-answers', function (req, res, next) {
        Answer.find({user:req.params.user_id}, function (err, answer) {
            if(err){
                return next(err);
            }
            res.json(answer);
        })
            .deepPopulate('item')

    })

我希望它用实际项替换id，并且项本身包含'ofBox'字段，我也想用实际的box文档替换（这就是为什么我使用deep-populate）。使用上面的查询根本不会给我任何结果。我仍然在项目字段中有ID。如果我运行标准.populate（'item'）命令，它会将项目ID替换为项目本身，但遗憾的是不是项目中的ofBox ID。（这就是为什么我需要深入填充）。

有人可以帮我解决一下吗？我想我在正确导入/注册插件时犯了一个错误......-.-

Answer 1

您需要在执行查询之前进行deepPopulate调用，如下所示：

＆＃13;

    // Alle Antworten des aktuellen Users laden
    // Verwendet von der Historie
    .get('/mm-answers/:user_id/get-all-answers', function (req, res, next) {
        Answer.find({ user: req.params.user_id }).deepPopulate('item').exec(function (err, answer) {
            if (err) {
                return next(err);
            }

            res.json(answer);
        });
    });

＆＃13;

Answer 2

在模型中，您只需要添加添加插件时要填充的字段：

 const mongoose = require('mongoose');
 const deepPopulate = require('mongoose-deep-populate')(mongoose);

    const MMAnswersSchema = new mongoose.Schema({
      user: { type: mongoose.Schema.Types.ObjectId, ref: 'User' },
      item: { type: mongoose.Schema.Types.ObjectId, ref: 'MMItem'},
      answer: [
        {
          skalaAnswer: Number,
          freitextAnswer: String,
          multipleChoiceAnswer: String,
          answered_at: { type: Date, required: true, default: Date.now }
        }
      ],
      last_answered: { type: Date, required: true, default: Date.now }
    });

    MMAnswersSchema.pre('save', function(next) {
      this.last_answered = Date.now;

      next();
    });



    MMAnswersSchema.plugin(deepPopulate, {
    populate: {
        user: {
            select:'_id name lastName'
        },
        item: {
            select:'_id name'
        },

        });
    const MMAnswers = mongoose.model('answers',MMAnswersSchema);
    module.exports = { MMAnswers };

最后，当您需要使用较深的人口时，只需添加您想填充的任何字段

await MMAnswers.findOne({your search}).deepPopulate('user').exec();

或

await MMAnswers.findOne({your search}).deepPopulate('user item').exec();

猫鼬深层填充物的用法不清楚

2 个答案: