Node.js 应用程序提供 ERR_EMPTY_RESPONSE

Question

我在使用 Node.js、Express、MongoDB 和 Mongoose 构建的应用程序时遇到了严重问题。昨晚，当我使用nodemon server.js 运行服务器时，一切似乎都正常了。在命令行上一切似乎都在工作，但在浏览器（特别是 Chrome）上，我收到以下错误：没有收到数据 ERR_EMPTY_RESPONSE。我已经在我的机器上尝试了其他 Node 项目，它们也都在努力工作。我昨晚做了一个 npm update 来更新我的模块，因为我从 MongoDB/Mongoose { [Error: Cannot find module '../build/Release/bson'] 代码：'MODULE_NOT_FOUND'} 得到另一个错误。我使用answer 中的解决方案尝试修复它，但它不起作用，我仍然收到该错误。现在我根本没有任何文件被提供给我的浏览器。我的代码如下。请帮忙：

//grab express and Mongoose
var express = require('express');
var mongoose = require('mongoose');
var Schema = mongoose.Schema;

//create an express app
var app = express();

app.use(express.static('/public/css', {"root": __dirname}));

//create a database
mongoose.connect('mongodb://localhost/__dirname');

//connect to the data store on the set up the database
var db = mongoose.connection;

//Create a model which connects to the schema and entries collection in the __dirname database
var Entry = mongoose.model("Entry", new Schema({date: 'date', link: 'string'}), "entries");

mongoose.connection.on("open", function() {
    console.log("mongodb is connected!");
});

//start the server on the port 8080
app.listen(8080);

//The routes

//The route for getting data for the database
app.get("/database", function(req, res) {
    Entry.find({}, function(err, data) {console.log(err, data, data.length); });

});

//The route for posting data on the database
app.post("/database", function(req, res) {
    //test new post
    var newMonth = new Entry({date: '1997-10-30', link: 'https://wwww.youtube.com/'});
        newMonth.save(function(err) {
            if (err !== null) {
                //object was not save
                console.log(err);
                    } else {
                console.log("it was saved!")
        };
    });
});



//create an express route for the home page at http://localhost:8080/
app.get('/', function(req, res) {
    res.send('ok');
    res.sendFile('/views/index.html', {"root": __dirname + ''});
});

//Send a message to the console
console.log('The server has started');

Answer 1

//The route for getting data for the database
app.get("/database", function(req, res) {
    Entry.find({}, function(err, data) {console.log(err, data, data.length); });

});

//The route for posting data on the database
app.post("/database", function(req, res) {
    //test new post
    var newMonth = new Entry({date: '1997-10-30', link: 'https://wwww.youtube.com/'});
        newMonth.save(function(err) {
            if (err !== null) {
                //object was not save
                console.log(err);
                    } else {
                console.log("it was saved!")
        };
    });
});

这些路由不会通过res 将任何内容发送回客户端。 bson 错误不是什么大问题 - 它只是告诉您它不能使用 C++ bson 解析器，而是使用本机 JS 解析器。

解决方法可能是：

//The route for getting data for the database
app.get("/database", function(req, res) {
    Entry.find({}, function(err, data) {
        if (err) { 
            res.status(404).json({"error":"not found","err":err});
            return;
        }
        res.json(data);
    });
});

//The route for posting data on the database
app.post("/database", function(req, res) {
    //test new post
    var newMonth = new Entry({date: '1997-10-30', link: 'https://wwww.youtube.com/'});
    newMonth.save(function(err) {
        if (err !== null) {
            res.status(500).json({ error: "save failed", err: err});
            return;
        } else {
            res.status(201).json(newMonth);
        };
    });
});

Answer 2

2020 年 6 月更新

ERR_EMPTY_RESPONSE express js

package.json

 "cors": "^2.8.4",
    "csurf": "^1.9.0",
    "express": "^4.15.4",

当您尝试使用错误的 HTTP 请求访问时会显示此错误。首先检查您的请求是否正确
也许你的 cors 参数错误