websocket 连接在写入文件时关闭

Question

so i am connecting a client to a server using websockets (ws). i successfully send msgs to the server and send it back to the client.Problem is when I try to write the received message to a file the server disconnects the client. The message is successfully written but i end up disconnecting client. Looks like something about the write functions disconnect my client. I am using fs.writFile(), I already tried fs.createWriteStream(). Reading the file however does not disconnect it.

const http = require('http');
const WebSocket = require('ws')
const fs = require('fs');

let counts = [0,0]
const server = http.createServer((req,res)=>{
    console.log(' Received request for ' + request.url);
});

const wss = new WebSocket.Server({ port: 8080 });

wss.on('connection',(ws)=>{
    console.log("serving...")

    ws.on('message',(message)=>{
        console.log("Received:"+message)

        if(message ==='1'){
            counts[0]=parseInt(counts[0])+1
            fs.writeFile('votecnts.txt',`${counts[0].toString()} ${counts[1].toString()}`,(err) =>{
                if(err) throw err
            })
        }
        else if (message==='2'){
            counts[1]=parseInt(counts[1])+1
            fs.writeFile('votecnts.txt',`${counts[0].toString()} ${counts[1].toString()}`,(err) =>{
                if(err) throw err
            })
        }
        else{console.log(typeof(message))}

        ws.send("cand_one: "+counts[0].toString()+"\n cand_two: "+counts[1].toString())    
    })



    ws.on('close',function(){
        console.log("lost client")
    })
})

Answer 1

So I figured it out. I was running both server and client on localhost while developing. And therefore the file directories are the same. I later found out that it is impossible to write to file in javascript at the client side because of security reasons. So all I did was to change the url of the server to a remote machine and I was able to write to file using server code. specifically with the writeFile() function in the code above. I actually did not have to touch my code. It was just about configuration and set up.