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Node JS TCP Server with simple password prompt problem

I'm trying to build a TCP server on node JS. The idea is to have multiple TCP clients connect and send / receive data(from server to client / client to server) and to have some sort of authentication (at least to enter a strong password) Also not sure if this approach is worth it. But, I've come up with something (most from online sources and docs) and crated below code.
Code runs and I can connect, but if I send data from client to server, the "password" check function fires up and each time I enter the correct password, a new (duplicate connection) is created. Seems like it keeps calling the same function on each input.
Desired behavior would be ; once client try's to connect, needs to provide the password and then start sending date. Also could someone give me a hint on how to send data back from server, or is it even possible. Or do I need to create a separate function for server.createConnection()
thanks in advance
UPDATE :I've changed the code a bit, but the main issue remains. this bit was supposed to check whether "clientAddress" exists and if so skip the auth part all together.
server.on('connection', (socket) => {
let clientAddress = `${socket.remoteAddress}:${socket.remotePort}`;
console.log(clientAddress)
if(sock.indexOf(clientAddress) !== -1){
console.log('devie found, opening communication')
newConnectionHandler(socket,clientAddress)
} else {
console.log('devie not found, need to authenticate')
userAuth(socket,clientAddress)
}
but as you can guess, it's not working :) if I manually specify the "clientAddress" it works , if I place "sock.push(clientAddress);" within the first block of code, it also works. No auth is asked. But when it's placed within
function userAuth(socket,clientAddress){
socket.write('password : ' )
socket.on('data', function (data) {
let pass = data.toString()
if (pass == password) {
sock.push(clientAddress);
console.log(sock)
newConnectionHandler(socket,clientAddress)
return;
} else {
//console.log(pass)
socket.write('Sorry, you cannot access the server \n')
console.log('acess denied for ' + socket.remoteAddress + ':' + socket.remotePort + '\n')
socket.write('connection closed')
socket.destroy()
}
})
}
code does run as expected and goes all the way till
function newConnectionHandler(socket,clientAddress){
//console.log(sock)
socket.write('Welcome \n')
socket.on('data', function(data1){
console.log("Client Sent: " + data1);
});
but as soon as I send a new message from the client, it goes back as if it was never authenticated and treats my input as the password and because it does not match with the actual password,it destroys the connection.
can someone please give me a hand...
const net = require('net');
const port = 3001;
const host = '192.168.0.165';
const server = net.createServer()
let sock = [];
let password = 123
//server.on('listening',createConnection);
server.on('connection', (socket) => {
let clientAddress = `${socket.remoteAddress}:${socket.remotePort}`;
console.log(clientAddress)
if(sock.indexOf(clientAddress) !== -1){
console.log('devie found, opening communication')
newConnectionHandler(socket,clientAddress)
} else {
console.log('devie not found, need to authenticate')
userAuth(socket,clientAddress)
}
server.on('error', errorHandler);
function errorHandler(err){
console.log(`Error occurred in ${clientAddress}: ${err.message}`);
}
function userAuth(socket,clientAddress){
socket.write('password : ' )
socket.on('data', function (data) {
let pass = data.toString()
if (pass == password) {
sock.push(clientAddress);
console.log(sock)
newConnectionHandler(socket,clientAddress)
return;
} else {
//console.log(pass)
socket.write('Sorry, you cannot access the server \n')
console.log('acess denied for ' + socket.remoteAddress + ':' + socket.remotePort + '\n')
socket.write('connection closed')
socket.destroy()
}
})
}
function newConnectionHandler(socket,clientAddress){
//console.log(sock)
socket.write('Welcome \n')
socket.on('data', function(data1){
console.log("Client Sent: " + data1);
});
socket.once('close', (data) => {
let index = sock.findIndex((o) => {
return o.remoteAddress === socket.remoteAddress && o.remotePort === socket.remotePort;
})
if (index !== -1) sock.splice(index, 1);
sock.forEach((sock) => {
socket.write(`${clientAddress} disconnected\n`);
        });
console.log(`connection closed: ${clientAddress}`);
    });
}
/* function createConnection(){
// Start a connection to the server
var socket = server.on('connect',function(){
// Send the initial message once connected
socket.write({question: "Hello, world?"});
});
// Whenever the server sends us an object...
socket.on('data', function(data){
// Output the answer property of the server's message to the console
console.log("Server's answer: " + data.answer);
});
} */
})
server.listen(port, host, () => {
console.log('TCP Server is running on port ' + port + '.');
});

so it appears as the only bit of code that was causing the authentication loop was the
function userAuth(socket,clientAddress){
socket.write('password : ' )
**socket.on('data', function (data) {**
let pass = data.toString()
after changing "on" with "once" it is now functioning properly. I tested with two TCP clients, both connected and was asked to enter a password. They can both actively send messages to the server and both disconnected properly in the end.
this is the code if anyone finds any use for it :) the connection it's self is still unencrypted so not good for sending/receiving sensitive data.
const net = require('net');
const port = 3001;
const host = '192.168.0.165';
const server = net.createServer()
let sock = [];
let password = 123
//server.on('listening',createConnection);
server.on('connection', (socket) => {
let clientAddress = `${socket.remoteAddress}:${socket.remotePort}`;
console.log(clientAddress)
if(sock.indexOf(clientAddress) !== -1){
console.log('devie found, opening communication')
newConnectionHandler(socket,clientAddress)
} else {
console.log('devie not found, need to authenticate')
userAuth(socket,clientAddress)
}
})
server.on('error', errorHandler);
function errorHandler(err){
console.log(`Error occurred in ${clientAddress}: ${err.message}`);
}
function userAuth(socket,clientAddress){
socket.write('password : ' )
socket.once('data', function (data) {
let pass = data.toString()
if (pass == password) {
sock.push(clientAddress);
console.log(sock)
newConnectionHandler(socket,clientAddress)
return;
} else {
//console.log(pass)
socket.write('Sorry, you cannot access the server \n')
console.log('acess denied for ' + socket.remoteAddress + ':' + socket.remotePort + '\n')
socket.write('connection closed')
socket.destroy()
}
})
}
function newConnectionHandler(socket,clientAddress){
//console.log(sock)
socket.write('Welcome \n')
socket.on('data', function(data1){
console.log("Client Sent: " + data1);
});
socket.on('close', function(data) {
let index = sock.findIndex(function(o) {
return o.remoteAddress === sock.remoteAddress && o.remotePort === sock.remotePort;
})
if (index !== -1) sock.splice(index, 1);
console.log('CLOSED: ' + socket.remoteAddress + ' ' + socket.remotePort);
});
}
/* function createConnection(){
// Start a connection to the server
var socket = server.on('connect',function(){
// Send the initial message once connected
socket.write({question: "Hello, world?"});
});
// Whenever the server sends us an object...
socket.on('data', function(data){
// Output the answer property of the server's message to the console
console.log("Server's answer: " + data.answer);
});
} */
server.listen(port, host, () => {
console.log('TCP Server is running on port ' + port + '.');
});

run multiple Jars in a given order with nodejs

I want to run two jars one after the other with nodejs but it seems like my program only stars the first jar :
The exec function :
execute a single shell command where "cmd" is a string
exports.exec = function(cmd, cb){
// this would be way easier on a shell/bash script :P
var child_process = require('child_process');
var parts = cmd.split(/\s+/g);
var p = child_process.spawn(parts[0], parts.slice(1), {stdio: 'inherit'});
p.on('exit', function(code){
var err = null;
if (code) {
err = new Error('command "'+ cmd +'" exited with wrong status code "'+ code +'"');
err.code = code;
err.cmd = cmd;
}
if (cb) cb(err);
});
};
Execute multiple commands in series this could be replaced by any flow control lib :
exports.series = function(cmds, cb){
var execNext = function(){
exports.exec(cmds.shift(), function(err){
if (err) {
cb(err);
} else {
if (cmds.length) execNext();
else cb(null);
}
});
};
execNext();
};
My use case :
shell.series([
`java -jar ${appDir}integration-tests/e2e-tests/tests/perf/uxcast-stub-0.27.0-jar-with-dependencies.jar`,
`java -jar ${appDir}integration-tests/e2e-tests/tests/perf/uxcast-app-0.27.0.jar`,
], err => {
if (err !== null) {
console.log('UXCAST ERROR -> ' + err);
return;
}
expect(startBrowser()).toBe('stuff');
done();
});
What I'm doing wrong ?

Nodejs server stop accept connections after a few hours

I made an application to the control of simultaneous logins, in starts everything works perfectly, however after a few hours i can not longer connect to the server, my client returns me the following error: net :: ERR_CONNECTION_TIMED_OUT and on the server side does not happen any error like it was running correctly... code below:
CLIENT SIDE:
var socket;
function connect(id) {
socket = io.connect('http://IP:4200');
socket.on('connect', function (data) {
socket.emit('join', id);
});
socket.on('messages', function (data) {
console.log('MSG: ' + data.toString());
switch (data.toString()) {
case "kick":
socket.close();
console.log("KICK!");
break;
case "duplicate_entry":
socket.close();
console.log("Another user connection!");
break;
}
});
}
SERVER SIDE:
var express = require('express');
var app = express();
var server = require('http').createServer(app);
var io = require('socket.io')(server);
var clients = [];
app.use(express.static(__dirname + '/bower_components'));
function logtimestamp() {
var log_date = new Date();
log_date = '[' + log_date.getFullYear() + '/' + (log_date.getMonth() + 1) + '/' + log_date.getDate() + ' ' + log_date.getHours() + ':' + log_date.getMinutes() + ':' + log_date.getSeconds() + ']';
return log_date;
}// FUNCTION logtimestamp
console.log("Start time: " + logtimestamp());
console.log("Server port 4200")
console.log("websocket server created!");
try {
io.on('connection', function (client) {
try {
var id;
var conexao;
client.on('join', function (data) {
try {
console.log('Client connected...'+logtimestamp()+' ID:' + data);
id = data;
conexao = {
ws: client,
id_user: data
};
clients.push(conexao);
for (var x = 0; x < clients.length; x++) {
//desconect previous user
try {
if (clients[x].id_user == id) {
if (clients[x].ws != conexao.ws) {
clients[x].ws.emit('messages', 'duplicate_entry');
clients.splice(x, 1);
}
}
} catch (err) {
console.log("ERROR 1: " + err.message);
}
}
} catch (err) {
console.log("ERROR 2: " + err.message);
}
});
} catch (err) {
console.log("ERROR 3: " + err.message);
}
});
} catch (err) {
console.log("ERROR 4: " + err.message);
}
server.listen(4200);

I see a couple possible issues. It is hard for us to know by just inspecting code which issues actually are the cause of your issue. In any case, you should clean up these issues and see if it improves the situation:
You should respond the the disconnect event and immediately remove any socket from your clients array when it disconnects.
In your loop where you are looking to removing any prior instances of a given user, your for loop will not work properly when you are doing .splice(x, 1) in the middle of the for loop. This will move all items after it does one in the array causing you to skip the comparison of the next element in the array. One simple way to get around this is to iterate the array backwards: for (var x = clients.length - 1; x >= 0; x--) because then the elements who's position are affected after the .splice() are elements you have already looked at. None will be missed.
Beyond this, you should examine the memory usage of the nodejs process, the open sockets by the nodejs process and the CPU usage of the nodejs process to see if any of those point to any possible issues.
And, what is your deployment environment? Is there a proxy server in front of your web server?

GraphicsMagick processes resulting in empty file

I'm doing this
gm(jpgName).setFormat('jpg')
.resize(160,158)
.compress('JPEG')
.write(fs.createWriteStream(jpgName),function(err){
if(err){
console.log(err,jpgName);
res.send(400);
}else{
console.log('file formated to jpg' + jpgName);
And I get
{ [Error: Command failed: gm convert: Empty input file (/home/ubuntu/node/uploads/icon.jpg). ] code: 1, signal: null }
If I stop the code right before the first line written here, and then look at the file, it has a file length. If I let this process happen (error out) then look at the file, then it has a size of 0 bytes.
I also tried this:
fs.stat(jpgName, function (err, stats) {
console.log('file size:',stats.size);
gm(jpgName).setFormat('jpg')
.resize(160,158)
.compress('JPEG')
.write(fs.createWriteStream(jpgName),function(err){
if(err){
console.log('console.log error writing jpg file',err,jpgName);
fs.unlink(jpgName);
callback(400);
return;
}else{//...
And I'm getting a file size back, so I know it's not empty before I start this process.
EDIT: I now start this process on form.on('end') so I could be sure the entire upload process was done.
The entire function:
function formatProfileImage(req,form,file,callback){
console.log('formatting profile image');
var ext = file.name.split('.')[1].toLowerCase();
var name = encodeURIComponent(file.name.split('.')[0].toLowerCase());
var smallName = form.uploadDir+"/"+"small_"+name+".jpg";
var jpgName = form.uploadDir + "/" + name+'.jpg';
console.log('extension:',ext);
console.log('name:',name);
console.log('smallName:',smallName);
console.log('jpgName:',jpgName);
if(!(ext == "png" || ext == "jpeg"|| ext == "jpg"|| ext == "gif")){
fs.unlink(file.path);
console.log("extension rejected");
callback(415);
return;
}
console.log('renaming file from ' + file.path + ' to ' + jpgName);
fs.rename(file.path,jpgName,function(err){
if(err){
console.log('error renaming file',err);
callback(400);
return;
}
console.log('file renamed');
fs.stat(jpgName, function (err, stats) {
console.log('file size:',stats.size);
if(!(typeof req.query.tenant === 'undefined')){
//rename to jpg
gm(jpgName).setFormat('jpg')
.resize(160,158)
.compress('JPEG')
.write(fs.createWriteStream(jpgName),function(err){
if(err){
console.log('console.log error writing jpg file',err,jpgName);
fs.unlink(jpgName);
callback(400);
return;
}else{
console.log('file formated to jpg' + jpgName);
//make "thumbnail"
gm(jpgName).setFormat('jpg')
.resize(50)
.write(fs.createWriteStream(smallName),function(err){
if(err){
fs.unlink(smallName);
console.log('error writing thumbnail',err,smallName);
callback(400);
return;
}else{
console.log('thumbnail created' + smallName);
//upload everything
uploadS3(jpgName,req.query.tenant,function(back){
if(back.success){
console.log('success ' +back.url);
callback(back.url);
fs.unlink(jpgName);
}else{
console.log('error uploading' + jpgName, back);
callback(400);
fs.unlink(jpgName);
return;
}
});
uploadS3(smallName,req.query.tenant,function(back){
if(back.success){
console.log('success ' +back.url);
fs.unlink(smallName);
}else{
console.log('error uploading ' + smallName, back);
callback(400);
fs.unlink(smallName);
return;
}
});
}
});
}
});
}
});
});
}

.write() accept string as path. So you need replace your stream with string (location, where resulting image must me saved).
GM support 3 ways of saving files.
1) Save to file. Simple, just use .write() and send as parameter string, where file should saved. Example:
gm('image.png')
.resize()
.write('resized.png', function (error) {
if (error) {
console.error(error);
}
});
2) Use streams, example:
gm('image.png')
.resize()
.stream(function (error, stdout, stderr) {
var writeStream = fs.createWriteStream('resized.jpg');
stdout.pipe(writeStream);
});
3) And last one - buffers:
gm('image.png')
.resize()
.toBuffer(function (error, buffer) {
if (error) {
console.error(error);
}
});

Transfer entire directory using ssh2 in Nodejs

I'm just wondering whether it is at all possible to transfer a directory from a unix server to my local machine using the ssh2 module in node.js. I have connected to the remote host and can read the directory as well as transfer single files, but there are 28 folders in the directory which each contain files and sub directories. What I'd like to do is take an exact copy of the main directory from the server to my local machine.
I was using fastGet with single files, but transferring a directory gives: Error: EISDIR, open __dirname/../localdirectory/ which I think implies I can't use fastGet to get an entire directory. I also tried using the exec command to try and scp it over, but I couldn't work out the syntax for the local directory:
// c is an active connection
c.exec('scp filethatexists.extension /../filepath/newname.extension', function(err, stream) {
if (err) {
console.log("error: " + err);
stream.end;
};
stream.on('data', function(data, extended) {
console.log((extended === 'stderr' ? 'STDERR: ' : 'STDOUT: ') + data);
});
stream.on('end', function() {
console.log('Stream :: EOF');
});
stream.on('close', function() {
console.log('Stream :: close');
});
stream.on('exit', function(code, signal) {
console.log('Stream :: exit :: code: ' + code + ', signal: ' + signal);
c.end();
});
});
This just results in the EOF calling. This code was just me testing If I could get a single file transferring.
Can anyone provide me with any assistance? Thank you in advance.

A couple of solutions:
You could recursively traverse the directory (making directories and transferring files as needed) using the sftp methods
Tar the directory (compress it too if you want) to stdout (e.g. tar cf - mydir) and then process that incoming stdout data with the tar module (and the built-in zlib module first if you end up compressing the directory).
// Requires:
// * `npm install tar-fs`
// * `ssh2` v0.5.x or newer
var tar = require('tar-fs');
var zlib = require('zlib');
function transferDir(conn, remotePath, localPath, compression, cb) {
var cmd = 'tar cf - "' + remotePath + '" 2>/dev/null';
if (typeof compression === 'function')
cb = compression;
else if (compression === true)
compression = 6;
if (typeof compression === 'number'
&& compression >= 1
&& compression <= 9)
cmd += ' | gzip -' + compression + 'c 2>/dev/null';
else
compression = undefined;
conn.exec(cmd, function(err, stream) {
if (err)
return cb(err);
var exitErr;
var tarStream = tar.extract(localPath);
tarStream.on('finish', function() {
cb(exitErr);
});
stream.on('exit', function(code, signal) {
if (typeof code === 'number' && code !== 0) {
exitErr = new Error('Remote process exited with code '
+ code);
} else if (signal) {
exitErr = new Error('Remote process killed with signal '
+ signal);
}
}).stderr.resume();
if (compression)
stream = stream.pipe(zlib.createGunzip());
stream.pipe(tarStream);
});
}
// USAGE ===============================================================
var ssh = require('ssh2');
var conn = new ssh();
conn.on('ready', function() {
transferDir(conn,
'/home/foo',
__dirname + '/download',
true, // uses compression with default level of 6
function(err) {
if (err) throw err;
console.log('Done transferring');
conn.end();
});
}).connect({
host: '192.168.100.10',
port: 22,
username: 'foo',
password: 'bar'
});

i m also trying to downlaod folders using ssh. It took me more than 10 days and i'm still trying to do that. But in the mean time i found some other code which will do the same thing for me.This code below will download every folder and file inside a directory
enter image description here