猫鼬验证外键(参考) [英] Mongoose Validate Foreign Key (ref)

问题描述

我尝试了几种不同的方法来验证Mongoose中的外键，但无法弄清楚.

I have tried several different ways to validate a foreign key in Mongoose and cannot figure it out.

我有一个这样的架构:

//Doctors.js
var schema = mongoose.Schema({
  email: { type: String }
}
module.exports = mongoose.model('Doctors', schema);

//Patients.js
var Doctors = require('./Doctors');
var schema = mongoose.Schema({
  email: { type: String },
  doctor: { type: String, ref: 'Doctors' }
}
schema.pre('save', function (next, req) {
  Doctors.findOne({email:req.body.email}, function (err, found) {
    if (found) return next();
    else return next(new Error({error:"not found"}));
  });
});
module.exports = mongoose.model('Patients', schema);

但是我收到此错误:Uncaught TypeError: Object #<Object> has no method 'findOne'

有人知道如何做与我在这里试图做的事情类似的事情吗?

Anyone know how to do something similar to what I am trying to do here?

推荐答案

在过去的一个小时里，我一直在使用Google进行搜索，并发现了一些有关范围的知识，这让我开始思考.以下代码解决了我的问题.

I kept googling over the past hour, and saw something about scope that got me thinking. The following code fixed my problem.

//Doctors.js
var mongoose = require('mongoose');
var schema = mongoose.Schema({
  email: { type: String }
}
module.exports = mongoose.model('Doctors', schema);

//Patients.js
//var Doctors = require('./Doctors'); --> delete this line
var mongoose = require('mongoose');
var schema = mongoose.Schema({
  email: { type: String },
  doctor: { type: String, ref: 'Doctors' }
}
schema.pre('save', function (next, req) {
  var Doctors = mongoose.model('Doctors'); //--> add this line
  Doctors.findOne({email:req.body.email}, function (err, found) {
    if (found) return next();
    else return next(new Error({error:"not found"}));
  });
});
module.exports = mongoose.model('Patients', schema);

尽管这是一个快速修复，但绝不是一个显而易见的修复(至少对我而言).问题是变量的范围.

Although this was a quick fix, in no way was it an obvious fix (at least to me). The issue was the scope of variables.

这篇关于猫鼬验证外键(参考)的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！