Node.js net socket - node.js

Question

I'm using the net module to create a listener but I've experienced some issues. I'm trying to make it wait till it's done writing the "text" to the client before the client can type again. If I'm not doing this and I hold in enter it'll just make you able to write enters between text leading to weird formatting etc.
So how could I make it wait till it's written to the client?
Code:
const net = require('net');
const server = new net.Server();
server.on('connection', async function (socket) {
console.log("Client connected!");
socket.on('data', async function (data) {
socket.setEncoding('utf8');
let input = data.toString().replace(/(\r\n|\n|\r)/gm, "");
if (input == "echo")
socket.write("$ ");
else
socket.write("invalid command");
});
});
server.listen(1337, function() {
console.log("listening");
});
Picture:
https://imgur.com/a/lc21Y13
Edit:
This is on localhost, let's say I'd host it on a server so there's a higher ping it's way worse.
Edit:
Here a picture from when it's hosted on a server:
https://imgur.com/a/LIKRRr9
Edit:
I've tried using SSH instead of telnet and raw and got basically the same result now.
Picture:
https://imgur.com/a/XJmpGSa
Code:
var fs = require('fs');
var username = null;
var ssh2 = require('ssh2');
new ssh2.Server({
hostKeys: [fs.readFileSync('ssh.key')]
}, function (client) {
console.log('Client connected!');
client.on('authentication', function (ctx) {
if (ctx.method !== 'password') return ctx.reject(['password']);
if (ctx.method === 'password') {
username = ctx.username;
console.log(username);
console.log(ctx.password);
ctx.accept();
}
else {
console.log("rejected.");
ctx.reject();
}
}).on('ready', function () {
console.log('Client authenticated!');
client.on('session', function (accept, reject) {
var session = accept();
session.once('shell', function (accept, reject, info) {
var stream = accept();
stream.write("$ ");
stream.on('data', function (data) {
var args = data.toString().split(" ");
console.log(args);
switch (args[0]) {
case "echo":
args.shift();
stream.write(args.join(" ") + "\r\n");
break;
case "whoami":
stream.write(username + "\r\n");
break;
case "exit":
stream.exit(0);
stream.end();
stream = undefined;
break;
default:
stream.stderr.write(args[0] + ": No such command!\r\n");
break;
}
if (typeof stream != 'undefined') {
stream.write("$ ");
}
});
});
});
}).on('end', function () {
console.log('Client disconnected');
});
}).listen(1337, function () {
console.log('Listening on port ' + this.address().port);
});

Answer 1

Try This. What this code does is simply buffering until \n enter is received from a client.
const net = require("net");
const readline = require("readline");
const execCommand = (command, args, socket) => {
return new Promise((res, rej) => {
setTimeout(() => {
// to clear the terminal
socket.write("\u001B[2J\u001B[0;0f");
socket.write(
`Executed command: ${command} with args: ${args} and result was: ${Math.random()}`
);
socket.write('\n>')
res();
}, 3000);
});
};
const server = net.createServer((socket) => {
socket.write("Connected");
// nice prompt
socket.write("\n>");
const rl = readline.createInterface({
input: socket,
output: socket,
});
rl.on("line", (line) => {
if (line.length === 0) {
socket.write("No command to execute!");
socket.write('\n>')
return;
}
// destructuring command and args
// E.g. command arg1 arg2 ....
const [command, ...args] = line.split(" ");
execCommand(command, args, socket);
});
});
server.listen(1337, "127.0.0.1");