Sending and Receiving Packages (packets) in Nodejs

Question

Well, I’ll try to explain the situation:

I am studying Nodejs and for this I decided to rewrite the server-side code of an application that was originally written in C/C++, and this server receives packages (packets) in hexadecimal of the client application, the question is: how to receive these packets (packets) in Nodejs ?

I came to create a socket for the connection but I gave a lock, follow the code done:

var port = process.env.PORT || 8281;
var io = require('socket.io')(port);

io.on('connection', function (socket) {
     var address = socket.handshake;
    console.log('Nova conexão de: ' + JSON.stringify(address, null, 4));
});

Answer 1

The basic class of Node.js used for TCP communication is called "net".

Below is an example of server and client made with the "net" class. The original (with comments) is in http://www.hacksparrow.com/tcp-socket-programming-in-node-js.html

---

server

var net = require('net');

var HOST = '127.0.0.1';
var PORT = 6969;

net.createServer(function(sock) {
    console.log('CONNECTED: ' + sock.remoteAddress +':'+ sock.remotePort);
    sock.on('data', function(data) {
        console.log('DATA ' + sock.remoteAddress + ': ' + data);
        sock.write('You said "' + data + '"');
    });
    sock.on('close', function(data) {
        console.log('CLOSED: ' + sock.remoteAddress +' '+ sock.remotePort);
    });

}).listen(PORT, HOST);

console.log('Server listening on ' + HOST +':'+ PORT);

---

client

var net = require('net');

var HOST = '127.0.0.1';
var PORT = 6969;

var client = new net.Socket();
client.connect(PORT, HOST, function() {
    console.log('CONNECTED TO: ' + HOST + ':' + PORT);
    client.write('I am Chuck Norris!');
});

client.on('data', function(data) {
    console.log('DATA: ' + data);
    client.destroy();
});

client.on('close', function() {
    console.log('Connection closed');
});

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