polling-xhr.js：229 GET http：// localhost：3000 / socket.io /？EIO = 4＆transport = polling＆t = NMtL4rR net

问题描述

我正在尝试构建一个表单，该表单在提交时发送带有填充数据的通知。当我运行代码时，它在控制台上向我显示此错误

polling-xhr.js：229 GET http：// localhost：3000 / socket.io /？EIO = 4＆transport = polling＆t = NMtL4rR net :: ERR_CONNECTION_REFUSED

此错误似乎是溢出

这是我的代码

admin.html

<!doctype html>
<html lang="en">
<head>
<!-- required Meta tags -->
<Meta charset="utf-8">
<Meta name="viewport" content="width=device-width,initial-scale=1,shrink-to-fit=no">

  <!-- Bootstrap CSS -->
   <link rel="stylesheet" 
  href="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/css/bootstrap.min.css" 
  integrity="sha384-TX8t27EcRE3e/ihU7zmQxVncDAy5uIKz4rEkgIXeMed4M0jlfIDPvg6uqKI2xXr2" 
  crossorigin="anonymous">

  <title>Hello,admin</title>
  </head>
  <body>
  <div class="container" style="max-width: 500px;">
    <div style="margin-top: 40px;"></div>
    <h1>Send Notification</h1>
    <form>
        <div class="form-group">
          <label for="name">name</label>
          <input type="text" class="form-control" id="name" aria-describedby="emailHelp">
        </div>
        <div class="form-group">
            <label for="profession">profession</label>
            <input type="text" class="form-control" id="profession" aria-describedby="emailHelp">
          </div>
          <div class="form-group">
            <label for="email">Email address</label>
            <input type="email" class="form-control" id="email" aria-describedby="emailHelp">
          </div>
       
       
        <button type="button" id="sendNotification" class="btn btn-primary">Submit</button>
      </form>
  </div>


 <!-- Optional JavaScript; choose one of the two! -->

 <!-- Option 1: jQuery and Bootstrap Bundle (includes Popper) -->
 <script src="https://code.jquery.com/jquery-3.5.1.slim.min.js" integrity="sha384- 
 DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
 <script src="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.bundle.min.js" 
   integrity="sha384-ho+j7jyWK8fNQe+A12Hb8AhRq26LrZ/JpcUGGOn+Y7RsweNrtN/tE3MoK7ZeZDyx" 
   crossorigin="anonymous"></script>
   <script src="https://cdnjs.cloudflare.com/ajax/libs/socket.io/3.0.1/socket.io.js"></script>

   <script type="text/javascript">
    var socket = io("http://localhost:3000");

    $( "#sendNotification" ).click(function() {

        var name = $( "#name" ).val()
        var profession = $( "#profession" ).val()
        var email = $( "#email" ).val()

        socket.emit("sendNotification",{
            "name" : name,"profession" : profession,"email" : email
        });
    });
</script>
</body>
</html>

user.html

<!doctype html>
<html lang="en">
<head>
<!-- required Meta tags -->
<Meta charset="utf-8">
<Meta name="viewport" content="width=device-width,shrink-to-fit=no">

 <!-- Bootstrap CSS -->
 <link rel="stylesheet" 
 href="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/css/bootstrap.min.css" 
 integrity="sha384-TX8t27EcRE3e/ihU7zmQxVncDAy5uIKz4rEkgIXeMed4M0jlfIDPvg6uqKI2xXr2" 
 crossorigin="anonymous">

 <title>Hello,user</title>
 </head>
 <body>
  <div class="container" style="max-width: 500px;">
    <div style="margin-top: 40px;"></div>
    <h1>Get Notification</h1>
    
  </div>



<script src="https://cdnjs.cloudflare.com/ajax/libs/socket.io/3.0.1/socket.io.js"></script>

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>

<script src="https://cdnjs.cloudflare.com/ajax/libs/notify/0.4.2/notify.js"></script>


<script type="text/javascript">
    var socket = io("http://localhost:3000");

    socket.on("sendNotification",function(details){
        $.notify("Name :"+details.name,{
            autoHide : false,className : "success"
        });
    });

    
</script>

<!-- Option 2: jQuery,Popper.js,and Bootstrap JS
<script src="https://code.jquery.com/jquery-3.5.1.slim.min.js" integrity="sha384- 
DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/popper.js@1.16.1/dist/umd/popper.min.js" integrity="sha384- 
9/reFTGAW83EW2RDu2S0VKaIzap3H66lZH81PoYlFhbGU+6BZp6G7niu735Sk7lN" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.min.js" 
integrity="sha384-w1Q4orYjBQndcko6MimVbzY0tgp4pWB4lZ7lr30WKz0vr/aWKhXdbnmNb5D92v7s" 
crossorigin="anonymous"></script>
-->
</body>
</html>

server.js

var express = require("express");
var app = express();

var http = require("http").createServer(app);
var io = require("socket.io")(http);

http.listen(3000,function(){
console.log("Successfully Connected Node Server");

 io.on("connection",function(socket){
    console.log("Auth value: " + socket.id);

    socket.on("sendNotification",function(details){
        socket.broadcast.emit("sendNotification",details);
    });
});
});

package.json

 {
 "name": "notification-server","version": "1.0.0","description": "Notification","main": "index.js","scripts": {
"test": "none"
 },"repository": {
"type": "git","url": "none"
 },"keywords": [
"none"
],"author": "cbra","license": "MIT","dependencies": {
"express": "^4.17.1","http": "0.0.1-security","socket.io": "^3.0.1"
}
}

我在这里需要更改什么？

解决方法

我认为您需要一个 CORS 模块。有两种方式

使用 npm

npm install cors

// server.js

...
app.use(require('cors')())
...

启用 CORS 选项（如果您使用的是 Socket.IO v3）

const io = require("socket.io")(http,{
    cors: {
        origin: "http://localhost:4200",methods: ["GET","POST"]
    }
})
http.listen(3000)

我有相同的讯息！我还尝试将服务器端链接到客户端。该代码有效，但是几天后我收到了此消息...

为什么会这样？

我通过在客户端放置“127.0.0.1:3000”而不是“https://localhost:3000”解决了这个错误。这是我的代码

var ip = '127.0.0.1:3000';

var socket = io.connect(ip);

server.js

var express = require("express");
var app = express();

var http = require("http").createServer(app);
var io = require("socket.io")(http);

http.listen(3000,function(){
console.log("Successfully Connected Node Server");

 io.on("connection",function(socket){
    console.log(socket)

    socket.on("sendNotification",function(details){
        socket.broadcast.emit("sendNotification",details);
    });
});
});

上面从服务器端首先检查登录套接字是否连接了套接字。然后在控制台日志检查有这样的标题：

      host: '127.0.0.1:3000',connection: 'keep-alive','sec-ch-ua': '" Not;A Brand";v="99","Google Chrome";v="91","Chromium";v="91"',accept: '*/*','sec-ch-ua-mobile': '?0','user-agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML,like Gecko) Chrome/91.0.4472.77 Safari/537.36',origin: 'http://localhost:3000','sec-fetch-site': 'cross-site','sec-fetch-mode': 'cors','sec-fetch-dest': 'empty',referer: 'http://localhost:3000/','accept-encoding': 'gzip,deflate,br','accept-language': 'en-GB,en-US;q=0.9,en;q=0.8'
    },```

So from console log you can see host is: 127.0.0.1:3000

include socket.io from the root path:

<script src="/socket.io/socket.io.js"></script>

Now on the front end script you can get io this way:

const socket = io('127.0.0.1:3000');


This should work

html javascript notifications