mongoose不会用findById返回输出

我正在学习nodejs和mongodb以获得MEAN应用程序

我的系统规格是

Ubuntu的16.04(64位)
节点v 6.1.0
npm v 3.8.6

“mongodb”:“^ 2.1.18”,
mongoose”:“^ 4.4.16”,

到目前为止,我已经创build了模式,并通过terminal使用db.locations.save()在mongodb集合中添加一个条目,并使用db.locations.save()获取生成的文档_id

db.locations.find()。pretty()在terminal返回输出

 { "_id" : ObjectId("57428745e89f5c55e1d057dc"), // and many other path } 

现在当我在浏览器中打开/ api / locations / 57428745e89f5c55e1d057dc时,它既不给出结果也不结束请求。 永久显示加载..当与邮递员testing。

甚至尝试与错误的ID比它返回适当的错误

{“message”:“在path\”_ id \“”,“name”:“CastError”,“kind”:“ObjectId”,“value”:“57428745e89f5c55e1d057dca”上投射到ObjectId的值“57428745e89f5c55e1d057dca”失败“path”: “_ ID”}

并用正确的ID

 console.log(mongoose.Types.ObjectId.isValid(req.params.locationid)); // return true 

甚至尝试过

findOne({"_id": mongoose.Types.ObjectId(req.params.locationid) })

但没有结果

可能是什么问题? 有没有mongoose或缺less任何错误。以下是我的基本文件与所需的代码

loc8r / app.js

 require('./app_api/models/db'); var routesApi = require('./app_api/routes/index'); app.use('/api', routesApi); 

loc8r / app_api /模型/ db.js

 var mongoose = require( 'mongoose' ); var mongoURI = 'mongodb://localhost/loc8r'; var mongoDB = mongoose.createConnection(mongoURI); mongoDB.on('connected', function (){ console.log('mongoose connected to ' + mongoURI); }); require('./locations'); 

loc8r / app_api /模型/ locations.js

 var mongoose = require( 'mongoose' ); var openingTimeSchema = new mongoose.Schema({ days: {type: String, required: true}, opening: String, closing: String, closed: {type: Boolean, required: true} }); var reviewSchema = new mongoose.Schema({ author: String, rating: {type: Number, required: true, min: 0, max: 5}, reviewText: String, createdOn: {type: Date, "default": Date.now} }); var locationSchema = new mongoose.Schema({ name: {type: String, required: true}, address: String, rating: {type: Number, "default": 0, min: 0, max: 5}, facilities: [String], coords: {type: [Number], index: '2dspehere'}, openingTime: [openingTimeSchema], reviews: [reviewSchema] }); mongoose.model('Location', locationSchema); 

loc8r / app_api /路由器/ index.js

 var express = require('express'); var router = express.Router(); var ctrlLocations = require('../controllers/locations'); /* Locations pages */ router.get('/locations/:locationid', ctrlLocations.locationsReadOne); 

loc8r / app_api /控制器/ locations.js

 var mongoose = require('mongoose'); var Loc = mongoose.model('Location'); module.exports.locationsReadOne = function (req, res) { if(req.params && req.params.locationid) { Loc .findById(req.params.locationid) .exec(function(err, location) { if(err) { sendJsonResponse(res, 404, err); return; } if (!location) { sendJsonResponse(res, 404, {"message": "locationid not found"}); return; } sendJsonResponse(res, 200, location); }); } else { sendJsonResponse(res, 200, {"message": "no location id in request"}); } } var sendJsonResponse = function(res, status, content) { res.status(status); res.json(content); }; 

       

网上收集的解决方案 "mongoose不会用findById返回输出"

从mongoose文档获得解决scheme

重要! 如果您使用mongoose.createConnection()打开单独的连接,但是尝试通过mongoose.model('ModelName')访问模型,它将无法按预期工作,因为它没有连接到活动数据库连接。 在这种情况下,通过您创build的连接访问您的模型:

所以改变我创build连接的方式

 //var mongoDB = mongoose.createConnection(mongoURI); mongoose.connect(mongoURI); 

还需要注释所有其他使用mongoDBvariables的函数/expression式


替代方法:(如果你不想在db.js中更改mongoDB

控制器/ locations.js

更改var Loc = mongoose.model('Location'); 与下面的线

 var conn = mongoose.createConnection('mongodb://localhost/loc8r'); var Loc = mongoose.model('Location'); 

尝试像这样重写位置控制器

 var mongoose = require('mongoose'), Location = mongoose.model('Location'); exports.locationsReadOne = function (req, res) { if (req.params && req.params.locationid) Location.findById(req.params.locationid, function (err, location) { if (err) return res.status(500).send(err); if (location) return res.status(200).json(location); return res.status(404).json({"message": "locationid not found"}) }) else return res.status(200).json({"message": "no location id in request"}) } 

嘿尝试通过将您的ID转换为对象ID

 var mongoose = require('mongoose'), Location = mongoose.model('Location'); exports.locationsReadOne = function (req, res) { if (req.params && req.params.locationid) Location.findById(mongoose.Types.ObjectId(req.params.locationid), function (err, location) { if (err) return res.status(500).send(err); if (location) return res.status(200).json(location); return res.status(404).json({"message": "locationid not found"}) }) else return res.status(200).json({"message": "no location id in request"}) } 

1.如果你以前安慰你的req.params

loc8r / app_api /控制器/ locations.js

 var mongoose = require('mongoose'); var Loc = mongoose.model('Location'); module.exports.locationsReadOne = function (req, res) { 

执行console.log(req.params)

  if(req.params && req.params.locationid) { Loc .findById(req.params.locationid) .exec(function(err, location) { if(err) { sendJsonResponse(res, 404, err); return; } if (!location) { sendJsonResponse(res, 404, {"message": "locationid not found"}); return; } sendJsonResponse(res, 200, location); }); } else { sendJsonResponse(res, 200, {"message": "no location id in request"}); } } var sendJsonResponse = function(res, status, content) { res.status(status); res.json(content); }; 

如果参数为空,或者控制台不工作,请检查您的pathpath

要么

  1. 控制台里面的东西sendJsonResponse,也许你的function不工作。 因为如果永久显示加载,这意味着你不发送回应。

要么

  1. 尝试更新mongodb到最新版本,也许mongoose工作与mongodb 2.1.18不正确。 它真的是非常旧的版本。