Question

我是新的 Nodejs socket.io 编程。我试图使用 Flutter Socket 客户端连接套接字。但是当我开始运行节点服务器时（下面的代码）。它打印在端口 3000 上运行的服务器。但是我收到错误 UnhandledPromiseRejectionWarning: TypeError: 无法读取未定义的属性“writeHead”。它也在最后显示。

UnhandledPromiseRejectionWarning：未处理的承诺拒绝。这个错误要么是因为在没有 catch 块的情况下抛出了异步函数，要么是因为拒绝了一个没有被处理过的承诺

const socketio = require('socket.io');
const express = require('express');
const app = express();

server = app.listen(3000);

//io server
const io = require("socket.io")(server);
//3000 or any other port.
const PORT = 3000 || process.env.PORT;

console.log(`Server running on port ${PORT}`);

var userConnection = [];

io.on('connection', (socket)=> 
{
try
{
    console.log(`nside connection`);
    
var other_users = userConnection.filter(p=> p.meeting_id == data.meetingid);    
// data saves to userConnection variable
// connection id and socket id are same
userConnection.push({
    connectionId: socket.id,
    user_id: data.current_user_name,
    meeting_id: data.meetingid,
})

}catch(e)
{
    console.log(e);


}

})

我得到的错误..


(node:11024) UnhandledPromiseRejectionWarning: TypeError: Cannot read property 'writeHead' of undefined
at sendErrorMessage (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:568:7)
at Server.handshake (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:291:7)
at Server.onWebSocket (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:460:12)
at D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:401:14
at WebSocketServer.completeUpgrade (D:\1ask\9105task\server145\node_modules\ws\lib\websocket-server.js:330:5)    at WebSocketServer.handleUpgrade (D:\1ask\9105task\server145\node_modules\ws\lib\websocket-server.js:246:10) 
at D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:400:15
at Server.verify (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:172:43)
at Server.handleUpgrade (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:384:10)
at Server.<anonymous> (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:511:16)

(node:11024) UnhandledPromiseRejectionWarning: TypeError: Cannot read property 'writeHead' of undefined at sendErrorMessage (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:568:7) at Server.handshake (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:291:7) at Server.onWebSocket (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:460:12) at D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:401:14 at WebSocketServer.completeUpgrade (D:\1ask\9105task\server145\node_modules\ws\lib\websocket-server.js:330:5) at WebSocketServer.handleUpgrade (D:\1ask\9105task\server145\node_modules\ws\lib\websocket-server.js:246:10) at D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:400:15 at Server.verify (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:172:43) at Server.handleUpgrade (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:384:10) at Server.<anonymous> (D:\1ask\9105task\server145\node_modules\engine.io\lib\server.js:511:16)

UnhandledPromiseRejectionWarning: TypeError: 无法读取未定义的属性“writeHead”

0 个答案: