使用Mongoose refPath动态填充数组对象字段失败问题排查

我尝试在Mongoose Schema中使用refPath指定填充数据的集合，写法与官方示例一致，但填充功能无法正常工作。手动指定model时填充可正常执行，但这种方式无法满足根据collectionType动态选择model的需求。

statesPersons Schema（包含activeWork对象数组） #

import mongoose, {model, Schema}  from "mongoose";

const statesPersonsSchema = new Schema(
  {
    profileId: {
      type: String,
      required: true,
      unique: true,
    },
    department: {
      type: String,
      required: true,
      index: true,
    },
    firstName: String,
    lastName: String,
    location: String,
    org: String,
    title: String,
    jobDescription: String,
    email: {
      type: String,
      lowercase: true,
    },
    phoneNumber: String,
    activeWork: ["activeWork"],
    emailList: [String],
    jobAssignments: [String],
    affiantInfo: {
      affiantInfoTitle: String,
      affiantInfoExperience: String,
    },
    assessments: [
      {
        assessdBy: {
          type: Schema.Types.ObjectId,
          ref: "statesPerson",
        },
        dueDate: Date,
        questions: {},
      },
    ],
  },
  { strictPopulate: false }
);

export default mongoose.model("statesPersons", statesPersonsSchema);

activeWork Schema（包含需填充的referenceId和指定集合类型的collectionType） #

import mongoose, {model, Schema}  from "mongoose";

const activeWorkSchema = new Schema(
  {
    active: Boolean,
    collectionType: {
      type: String,
      enum: ["messages", "cases"],
    },
    referenceId: {
      type: Schema.Types.ObjectId,
      refPath: "collectionType",
    },
    sentBy: {
      type: Schema.Types.String,
      ref: "statesPersons",
    },
    sentTo: {
      type: Schema.Types.String,
      ref: "statesPersons",
    },
    timeRecived: Date,
    dueDate: Date,
    subject: String,
    viewed: Boolean,
    content: {},
  },
  { strictPopulate: false }
);

export default mongoose.model("activeWork", activeWorkSchema);

查询代码 #

export async function getStatesPersonsActiveWorkByProfileId(req, res){
    mongoose.set('debug', true);
    try{
        const { profileId } = req.params

        const data = await statesPersons
        .find({ profileId })
        .populate('statesPersons.activeWork.referenceId')
        .exec()
        
        return res.send({
            message: "success",
             data: data,
             status: 200 })
    }catch(e) {
        console.error(e.message)
        return res.send({
            message: "couldn't fetch active work",
             data: null,
             status: 500 })
    }
}

问题现象 #

返回结果中，statesPersons对象的activeWork仅保留需要填充的ObjectId，未完成填充：

"activeWork": [
    {
        "active": true,
        "collectionType": "messages",
        "referenceId": "63a49e3052658ce60c1dafcb",
        "sentBy": "108416469928574003772",
        "dueDate": "2018-02-21T11:16:50.362Z",
        "subject": "testing",
        "viewed": false,
        "_id": "63a49e3052658ce60c1dafce"
    }
]

可行但不符合需求的写法 #

手动指定model时填充可正常工作，但无法动态切换集合：

const data = await statesPersons
.find({ profileId })
.populate({path: 'activeWork.referenceId', model: 'messages'})
.exec()

内容的提问来源于stack exchange，提问作者Nick Woffard