使用 Node.js 的 MongoDB 引用我无法填充

Posted 2023-03-10

【中文标题】使用 Node.js 的 MongoDB 引用我无法填充

【英文标题】：MongoDB references with Node.js I can not populate

【发布时间】：2017-05-05 21:29:18

【问题描述】：

我想在屏幕上显示用户的位置信息。

例如：

name: "Andy" surname : "Carol" City : "Istanbul"  Town : "Kadıkoy"

当我调用getuser 函数时，我想显示城市和城镇名称。

这是我的代码：

用户模式

// Model for the User 
module.exports = (function userSchema() 

  var Mongoose = require('mongoose');
  var Schema = Mongoose.Schema;

  var userSchema = new Schema(

    name: 
      type: String,
      require: true
    ,
    surname: 
      type: String,
      require: true
    ,
    tel: 
      type: String,
      require: true
    ,
    age: 
      type: String,
      require: true
    ,
    mevki_id: 
      type: String,
      require: true
    ,
    lok_id: [
      type: Mongoose.Schema.Types.ObjectId,
      ref: 'locations'
    ]

  );

  var collectionName = 'users';
  var USERSCHEMA = Mongoose.Schema(userSchema);
  var User = Mongoose.model(collectionName, USERSCHEMA);

  return User;

)();

用户控制器

//This Controller deals with all functionalities of User
function userController() 

  var User = require('../models/UserSchema');

  // Creating New User
  this.createUser = function (req, res, next) 

    var name = req.body.name;
    var surname = req.body.surname;
    var tel = req.body.tel;
    var age = req.body.age;
    var mevki_id = req.body.mevki_id;
    var lok_id = req.body.lok_id;

    User.create(
      name: name,
      surname: surname,
      tel: tel,
      age: age,
      mevki_id: mevki_id,
      lok_id: lok_id
    , function (err, result) 
      if (err) 
        console.log(err);
        return res.send(
          'error': err
        );
       else 
        return res.send(
          'result': result,
          'status': 'successfully saved'
        );
      
    );
  ;

  //Populateeee

  this.getUser = function (req, res, next) 

    User.find().populate('lok_id')
      .exec(function (err, result) 
        if (err) 
          console.log(err);
          return res.send(
            'error': err
          );
         else 
          return res.send(
            'USERS': result
          );
        
      );
  ;

  return this;

;

module.exports = new UserController();

位置架构

//Schema for Location
module.exports = (function LocationSchema() 

  var Mongoose = require('mongoose');
  var Schema = Mongoose.Schema;

  var LocationSchema = new Schema(

    userid: 
      type: Mongoose.Schema.Types.ObjectId,
      ref: 'users'
    ,

    il: 
      type: String,
      require: true
    ,

    ilce: 
      type: String,
      require: true
    

  );

  var collectionName = 'locations';
  var LocationSCHEMA = Mongoose.Schema(schema);
  var Location = Mongoose.model(collectionName, LocationSCHEMA);

  return Location;
)();

位置控制器

//This Controller deals with all functionalities of Location
function locationController() 
  var location = require('../models/LocationSchema');

  // Creating New Location
  this.createLocation = function (req, res, next) 
    var userid = req.params.userid;
    var il = req.params.il;
    var ilce = req.params.ilce;

    location.create(
      userid: userid,
      il: il,
      ilce: ilce
    , function (err, result) 
      if (err) 
        console.log(err);
        return res.send(
          'error': err
        );
       else 
        return res.send(
          'result': result,
          'status': 'successfully saved'
        );
      
    );
  ;

  // Fetching Details of Location
  this.getLocation = function (req, res, next) 

    location.find(, function (err, result) 
      if (err) 
        console.log(err);
        return res.send(
          'error': err
        );
       else 
        console.log(result);
        return res.send(
          'location Details': result
        );
      
    );
  ;

  return this;

;

module.exports = new locationController();

【问题讨论】：

位置架构 i.imgsafe.org/93f9ceb4fa.jpg LocationController i.imgsafe.org/93f9b72897.jpg

最好将代码包含为文本而不是位于外部站点的屏幕截图。

我编辑了你

【参考方案1】：

我已经遇到了模型定义问题。 通过将第三个参数添加到 mongoose.model（显式集合名称）来修复它

// Try to replace :
var collectionName = 'users';	
var USERSCHEMA=Mongoose.Schema(userSchema);
var User = Mongoose.model(collectionName, USERSCHEMA);
// with:
var collectionName = 'users';	
var USERSCHEMA=Mongoose.Schema(userSchema);
var User = Mongoose.model(collectionName, USERSCHEMA, collectionName);

collectionName 必须在模式定义或模型定义中设置。更多详情见here

【讨论】：

你说的对，但我的创建用户函数是错误的，你可以在用户控制器中查看这个函数吗？