egg(29)--mongoose使用聚合管道多表关联查询

db.js

var mongoose = require('mongoose');
mongoose.connect('mongodb://eggadmin:123456@127.0.0.1:27017/eggcms',{ useNewUrlParser: true },function(err){
    if(err){
        console.log(err)
        return
    }
    console.log("数据库连接成功")
})

module.exports = mongoose;

articlecate.js

var mongoose = require('./db.js');
var ArticleCateSchema = mongoose.Schema({
    title:{
        type:String,
        unique:true
    },
    description:String,
    addtime:{
        type:Date,
        default:Date.now
    }
})

var ArticleCateSchema = mongoose.model('ArticleCate',ArticleCateSchema,'articleCate');
module.exports = ArticleCateSchema

user.js

var mongoose = require('./db.js');
var UserSchema = mongoose.Schema({
    username:{
        type:String,
        unique:true
    },
    password:String,
    name:String,
    age:Number,
    tel:Number,
    status:{
        type:Number,
        default:1
    }
})

var UserSchema = mongoose.model('User',UserSchema,'user');
module.exports = UserSchema

article.js

var mongoose = require('./db.js');
var ArticleSchema = mongoose.Schema({
    title:{
        type:String,
        unique:true
    },
    cid:{//分类id
        type:mongoose.Types.ObjectId
    },
    author_id:{//用户id
        type:mongoose.Types.ObjectId
    },
    author_name:{
        type:String
    },
    description:String,
    content:String
})

var ArticleSchema = mongoose.model('Article',ArticleSchema,'article');
module.exports = ArticleSchema

新增数据

app.js

var mongoose = require("mongoose")
var ArticleCateModel = require('./articlecate.js');
var ArticleModel = require('./article.js');
var UserModel = require('./user.js');

var cate = new ArticleCateModel({
    title:"广东新闻",
    description:"广东新闻"
})
cate.save()

var user = new UserModel({
    username:"lishi",
    password:"123456",
    name:"李四",
    age:20,
    tel:[phone]
})
user.save()

var article = new ArticleModel({
    // title:"习访问美国",
    title:"广东新闻发生大火",
    // cid:"5c00d3dcceb92704e4d30248", //国际
    cid:"5c00d400a7998c2a885ab9ba", //国内
    // author_id:"5c00d46fb004c9247c6f90ca",  //张三
    cid:"5c00d82bf252ca209c90facb",
    author_id:"5c00d47be5fcb430b0cbf290",  //李四
    // 5c00d47be5fcb430b0cbf290,李四
    // author_name:"张三",
    author_name:"李四",
    description:"东莞发生大火........",
    content:"东莞发生大火........"
})
article.save()

查询数据

app.js

var ArticleModel = require('./article.js');
ArticleModel.aggregate([{
    $lookup: {
        from: 'articleCate',
        localField: "cid",
        foreignField: "_id",
        as: "cate"
    }
}, {
    $lookup: {
        from: 'user',
        localField: "author_id",
        foreignField: "_id",
        as: "user"
    }
}], function (err, docs) {
    if (err) {
        console.log(err);
        return;
    }
    console.log(JSON.stringify(docs))
})