node.js - Mongoose ，根据外键/填充键排序

Question

我有两个带有 mongoose 的模式(AgendaCompromissoSchema 和 profissionaisSchema)。

我想找到一组按 profissional.name 降序排列的所有 AgendaCompromisso。

我更喜欢单独的模式而不是嵌套文档。

我已经尝试了下一个代码但没有成功。

    router.get('/',function(req,res,next){  
        AgendaCompromisso.find({})
        .populate('profissional',name') //here I´d like the results sorted by 'name' descending
        .sort:{
           'profissional.name': -1 //Sort by name Added DESC
         }        
         .exec( (err,data) => {
           callback(err,data,res)
        })
    });

//路由器

const express = require('express');
const router = express.Router();
const AgendaCompromisso = require('../models/agendaCompromisso');
const callback=function(err,data,res){
     //console.log(data);
     if (err) return res.status(500).json(err);
     return res.status(200).send(data);
}   

//get all
router.get('/',function(req,res,next){  
    AgendaCompromisso.find({})
    .populate('profissional','name')
    .exec( (err,data) => {
       callback(err,data,res)
    })
});

//模式

var AgendaCompromissoSchema = new mongoose.Schema({
  profissional:{type:mongoose.Schema.Types.ObjectId, ref:'Profissional'},
  title:{type:String},
  slot_dateInit:{type: Date},
  slot_timeInit:{type: Date}
});
module.exports = mongoose.model('AgendaCompromisso',  AgendaCompromissoSchema,'agendasCompromissos' );

var profissionaisSchema = new mongoose.Schema({
  name: {type: String, unique:true},
  cpf: {type: String},
});

module.exports = mongoose.model('Profissional', profissionaisSchema,'profissionais' );

Answer 1

使用 $lookup aggregation pipeline中(执行left outer join，类似于sql)可以解决这个问题:

router.get('/',function(req,res,next){  
    AgendaCompromisso.aggregate([
    {
        $lookup:
        {
            from: "profissionais", //use the name of database collection not mongoose model
            localField: "profissional",
            foreignField: "_id",
            as: "profissional_doc"
        }
    },

    {
        $unwind: "$profissional_doc"  //remove array
    },

    {
        $sort: {"profissional_doc": -1}  // or {"profissional_doc": 1} for ascending
    }
    ])
    .exec( (err,data) => {
        callback(err,data,res)
    })
});

请注意，要进行查找，您需要 mongodb 版本 3.2 或更高版本。