Mongoose 聚合 $match 不匹配

Question

我有一组对象，其中每个对象包含一个 Action 对象数组和一个子对象。我想从一个特定的子 ID 对象中总结操作点。

当我在 mongoplayground https://mongoplayground.net/ 测试总和时它按预期工作，但在代码中，它不是很好。请有人帮我指出我在这里遗漏了什么？

下面是我的文件:

数组

[
    {
        "_id": "5e6990148c3e01001388b678",
        "child": {
            "image": "",
            "_id": "5e695fe97bd186001526798d",
            "name": "Mariana",
            "gender": "female",
            "dateBirth": "12/07/2010",
            "createdAt": "2020-03-11T22:02:17.413Z",
            "updatedAt": "2020-03-11T22:02:17.413Z",
            "__v": 0
        },
        "actions": [
            {
                "_id": "5e6990148c3e01001388b679",
                "type": "extraNegativePoint",
                "point": -10,
                "pointType": "red",
                "createdAt": "2020-03-12T01:27:48.747Z",
                "updatedAt": "2020-03-12T01:27:48.747Z"
            },
            {
                "_id": "5e6990148c3e01001388b67a",
                "type": "extraNegativePoint",
                "point": -10,
                "pointType": "red",
                "createdAt": "2020-03-12T01:27:48.747Z",
                "updatedAt": "2020-03-12T01:27:48.747Z"
            },
            {
                "_id": "5e6990148c3e01001388b67b",
                "type": "extraNegativePoint",
                "point": -10,
                "pointType": "red",
                "createdAt": "2020-03-12T01:27:48.747Z",
                "updatedAt": "2020-03-12T01:27:48.747Z"
            }
        ],
        "createdAt": "2020-03-12T01:27:48.748Z",
        "updatedAt": "2020-03-12T01:27:48.748Z",
        "__v": 0
    },
    {
        "_id": "5e6990578c3e01001388b67c",
        "child": {
            "image": "",
            "_id": "5e644fecffc3150013eeafba",
            "name": "Sheldon",
            "gender": "male",
            "dateBirth": "25/01/2014",
            "createdAt": "2020-03-08T01:52:44.878Z",
            "updatedAt": "2020-03-08T01:52:44.878Z",
            "__v": 0
        },
        "actions": [
            {
                "_id": "5e6990578c3e01001388b67d",
                "type": "extraNegativePoint",
                "point": -10,
                "pointType": "red",
                "createdAt": "2020-03-12T01:28:55.922Z",
                "updatedAt": "2020-03-12T01:28:55.922Z"
            },
            {
                "_id": "5e6990578c3e01001388b67e",
                "type": "extraNegativePoint",
                "point": -10,
                "pointType": "red",
                "createdAt": "2020-03-12T01:28:55.922Z",
                "updatedAt": "2020-03-12T01:28:55.922Z"
            },
            {
                "_id": "5e6990578c3e01001388b67f",
                "type": "extraNegativePoint",
                "point": -10,
                "pointType": "red",
                "createdAt": "2020-03-12T01:28:55.923Z",
                "updatedAt": "2020-03-12T01:28:55.923Z"
            },
            {
                "_id": "5e6990598c3e01001388b680",
                "type": "extraNegativePoint",
                "point": -10,
                "pointType": "red",
                "createdAt": "2020-03-12T01:28:57.428Z",
                "updatedAt": "2020-03-12T01:28:57.428Z"
            },
            {
                "_id": "5e6990598c3e01001388b681",
                "type": "extraNegativePoint",
                "point": -10,
                "pointType": "red",
                "createdAt": "2020-03-12T01:28:57.428Z",
                "updatedAt": "2020-03-12T01:28:57.428Z"
            },
            {
                "_id": "5e6990598c3e01001388b682",
                "type": "extraNegativePoint",
                "point": -10,
                "pointType": "red",
                "createdAt": "2020-03-12T01:28:57.428Z",
                "updatedAt": "2020-03-12T01:28:57.428Z"
            }
        ],
        "createdAt": "2020-03-12T01:28:55.923Z",
        "updatedAt": "2020-03-12T01:28:57.431Z",
        "__v": 1
    }
]

架构

const mongoose = require('mongoose');
const Schema = mongoose.Schema;
const Promise = require('promise')

const actionSchema = new Schema({
    type: {
        type: String,
        required: true
    },
    point: {
        type: Number,
        min: -1001,
        max: 1001,
        required: true
    },
    pointType: {
        type: String,
        required: true
    },
    goal:{
        type: mongoose.Schema.Types.ObjectId,
        ref: 'Goals'
    }, 
    penalty: {
        type: mongoose.Schema.Types.ObjectId,
        ref: 'Penalty'
    },
    award: {
        type: mongoose.Schema.Types.ObjectId,
        ref: 'Award'
    }
},{
    timestamps: true
})

const realizationSchema = new Schema({
    child: {
        type: mongoose.Schema.Types.ObjectId,
        ref: 'Child'
    },
    actions: [actionSchema]
},
{
    timestamps: true
});

realizationSchema.statics.fetchTotalPointsPerChild = function(childId) {
    return new Promise((resolve, reject) => {
        this.aggregate([
            {
                $match: {
                    "child._id": childId
                }
            },
            {
                $unwind: "$actions"
            },
            {
                $group: {
                    _id: "$child._id",
                    totalPointsPerChild: {
                        $sum: "$actions.point"
                    }
                }
            }], 

                (err, result) => {
                    if (err) {
                        console.log("Error from search: fetchTotalPointsPerChild", err)
                        return reject(err);
                    }
                    resolve(result)
                }
            )
            });
       }
module.exports = mongoose.model('Realization', realizationSchema);

router

        realizationRouter.route('/:childId/actions/totalPoints')
        .get((req, res, next) => {
           Realization.find()
           .populate('child')
           .populate('goals')
           .populate('penalty')
           .then(realization => {
              if(realization) {

                Realization.fetchTotalPointsPerChild(JSON.stringfy(req.params.childId))
                .then(result => {
                    if(result){
                        res.statusCode = 200;
                        res.setHeader('Content-Type', 'application/json');
                        res.json(result);
                    }
                })
                .catch(err => next(err));
            } else {
                res.statusCode = 200;
                res.setHeader('Content-Type', 'application/json');
                res.json(`There is no action to show from this child ${req.params.childId}`);
            }
        })

            .catch(err => next(err));
    });
 module.exports = realizationRouter;

Answer 1

您正在尝试聚合错误的示例文档，因为根据架构，操作字段只是一个 ObjectId 而不是对象。它应该只是 "child": ObjectId("5e644fecffc3150013eeafba")。

所以你的聚合必须是这样的:

realizationSchema.statics.fetchTotalPointsPerChild = function(childId) {
  return new Promise((resolve, reject) => {
    this.aggregate(
      [
        {
          $match: {
            child: mongoose.Types.ObjectId(childId) //NOT  "child._id": childId
          }
        },
        {
          $unwind: "$actions"
        },
        {
          $group: {
            _id: "$child", //NOT _id: "$child._id",
            totalPointsPerChild: {
              $sum: "$actions.point"
            }
          }
        }
      ],
      (err, result) => {
        if (err) {
          console.log("Error from search: fetchTotalPointsPerChild", err);
          return reject(err);
        }
        console.log(result); 
        resolve(result);
      }
    );
  });
};

console.log(result) 将在控制台中显示:

[ { _id: 5e644fecffc3150013eeafba, totalPointsPerChild: -60 } ]

Playground