Mongoose：如何防止mongodb在数据库中保存重复的电子邮件记录

3 回答

• 3

  Async Custom Validator

  var userSchema = new mongoose.Schema({
      password: String,
      email: {
          type: String,
          lowercase: true,
          required: true,
          validate: {
              isAsync: true,
              validator: function(value, isValid) {
                  const self = this;
                  return self.constructor.findOne({ email: value })
                  .exec(function(err, user){
                      if(err){
                          throw err;
                      }
                      else if(user) {
                          if(self.id === user.id) {  // if finding and saving then it's valid even for existing email
                              return isValid(true);
                          }
                          return isValid(false);  
                      }
                      else{
                          return isValid(true);
                      }
  
                  })
              },
              message:  'The email address is already taken!'
          },
      }
  });
  

  您可能希望将验证程序代码更改为es6 .

  回复于 2024-05-03T18:49:47+08:00
• 1

  我实现了以下代码以查看是否有任何错误：

  var mongoose = require('mongoose');
  var bodyParser = require('body-parser');
  var express = require('express');
  var http = require('http');
  
  var app = express();
  
  app.use(bodyParser.json());
  app.use(bodyParser.urlencoded({ extended: false }));
  
  var Schema = mongoose.Schema;
  
  mongoose.connect('mongodb://localhost/test');
  
  // Create a schema
  var userSchema = new mongoose.Schema({
      email: { type: String, required: true, unique: true},
      password: String
  });
  
  var userModel = mongoose.model("user", userSchema);
  
  app.post('/postuser', (req, res) => {
    console.log('Requested data to server: ' + JSON.stringify(req.body._user));
    var user = new userModel({
        email: req.body._user.email,
        password: req.body._user.password
    });
    // user.isNew = false;
    user.save((err, data) => {
        console.log('Analyzing Data...');
        if(data) {
            console.log('Your data has been successfully saved.');
            res.json(data);
        }
        else {
          console.log('Something went wrong while saving data.');
          console.log(err);
          res.send(err);
        }
    })
  });
  
  http.createServer(app).listen(3000, function(){
    console.log('Express server listening on port 3000');
  });
  

  我确保在我的本地MongoDB数据库中没有 users 名称的集合 . 此外，我使用Postman在 http://localhost:3000 向我的服务器发送API请求 . 似乎没有问题，因为我继续添加具有不同电子邮件值的用户 . 当我输入具有重复值的电子邮件时，我只收到以下错误

  {
    "code": 11000,
    "index": 0,
    "errmsg": "E11000 duplicate key error collection: test.users index: email_1 dup key: { : \"hot@mail.com\" }",
    "op": {
      "email": "hot@mail.com",
      "password": "1234567",
      "_id": "5919a3428c13271f6f6eab0f",
      "__v": 0
    }
  }
  

  这些是我发送的JSON请求：

  {"_user": {"email": "hot@mail.com", "password": "1234"}}
  {"_user": {"email": "sammy@mail.com", "password": "1234"}}
  {"_user": {"email": "tommy@mail.com", "password": "1234"}}
  {"_user": {"email": "tommy@mail.ae", "password": "1234567"}}
  {"_user": {"email": "hot@mail.com", "password": "1234567"}}
  

  上面提到的错误是在最后一次请求时发回的，因为重复了电子邮件 hot@mail.com . 如果您查看链接http://mongoosejs.com/docs/api.html#schematype_SchemaType-unique，则'll see that the E11000 error is only sent when the email entered is not unique. Moreover, your email can' t为空字符串或不存在，因为它违反了必需的属性 .

  回复于 2024-05-03T18:49:47+08:00
• 0

  A short answer using this tool mongoose-unique-validator

  npm install --save mongoose-unique-validator
  

  在你的模型中

  var mongoose = require('mongoose')
  var uniqueValidator = require('mongoose-unique-validator')
  var userSchema = new mongoose.Schema({
      email: { type: String, required: true, unique: true},
      password: String
  });
  
  userSchema.plugin(uniqueValidator)
  var userModel = mongoose.model("user", userSchema);
  

  That's it! (Notice unique: true)

  现在，您的收藏中没有电子邮件重复 .

  奖金！ ：你可以访问错误

  .catch(err => console.log(err))
  

  所以在你的例子中

  // user.isNew = false;
  user.save((err, data) => {
      console.log('Analyzing Data...');
      if(data) {
          console.log('Your data has been successfully saved.');
          res.json(data);
  }
  else {
    console.log('Something went wrong while saving data.');
    console.log(err);
    res.send(err);
  }
  

  访问错误>>所以你可以res.send（err.message）>>'验证失败'

  {
      message: 'Validation failed',
      name: 'ValidationError',
      errors: {
          email: {
              message: 'Error, expected `email` to be unique. Value: `example@gmail.com`',
              name: 'ValidatorError',
              kind: 'unique',
              path: 'email',
              value: 'example@gmail.com'
          }
      }
      }
  

  回复于 2024-05-03T18:49:47+08:00