React Native Websocket outside access - javascript

Im trying to send an answer to my websocket-server from a component which does not contain the websocket. My Websocket server looks like this:
componentDidMount() {
var ws = new WebSocket('ws:// URL');
ws.onmessage = this.handleMessage.bind(this);
...
}
How can I pass the "var ws" to another class or component. Or is it possible to make the websocket globally accessable?
Thank you very much for any help!

I found a solution with help from this question in stackoverflow:
visit:
React native: Always running component
I created a new class WebsocketController like this:
let instance = null;
class WebsocketController{
constructor() {
if(!instance){
instance = this;
}
this.ws = new WebSocket('ws://URL');
return instance;
}
}
export default WebsocketController
And then in my other class where I need my websocket I just called it like this:
let controller = new WebsocketController();
var ws = controller.ws;
 

websocket connection
keep this code in some file, name it with .js extenstion. ex: websocket.js
var WebSocketServer = require("ws").Server;
var wss = new WebSocketServer({port:8100});
wss.broadcast = function broadcast(msg) {
console.log(msg);
wss.clients.forEach(function each(client) {
client.send(msg);
});
};
wss.on('connection', function connection(ws) {
// Store the remote systems IP address as "remoteIp".
var remoteIp = ws.upgradeReq.connection.remoteAddress;
// Print a log with the IP of the client that connected.
console.log('Connection received: ', remoteIp);
ws.send('You successfully connected to the websocket.');
ws.on('message',wss.broadcast);
});
In your app/website side. create .js file. Ex: client.js
var SERVER_URL = 'ws://127.0.0.1:8100';
var ws;
function connect() {
//alert('connect');
ws = new WebSocket(SERVER_URL, []);
// Set the function to be called when a message is received.
ws.onmessage = handleMessageReceived;
// Set the function to be called when we have connected to the server.
ws.onopen = handleConnected;
// Set the function to be called when an error occurs.
ws.onerror = handleError;
}
function handleMessageReceived(data) {
// Simply call logMessage(), passing the received data.
logMessage(data.data);
}
function handleConnected(data) {
// Create a log message which explains what has happened and includes
// the url we have connected too.
var logMsg = 'Connected to server: ' + data.target.url;
// Add the message to the log.
logMessage(logMsg)
ws.send("hi am raj");
}
function handleError(err) {
// Print the error to the console so we can debug it.
console.log("Error: ", err);
}
function logMessage(msg) {
// $apply() ensures that the elements on the page are updated
// with the new message.
$scope.$apply(function() {
//Append out new message to our message log. The \n means new line.
$scope.messageLog = $scope.messageLog + msg + "\n";
});
}
Please let me know if you face any issue with this code

Related

Connect JS secure websocket to C# websocket server (Fleck)

I have an API in C# (asp.net) in which i'm running this websocket server using fleck:
SocketService.start();
SocketService.server.Start(socket =>
{
socket.OnOpen = () =>
{
SocketService.Connessione(socket);
};
socket.OnClose = () =>
{
SocketService.Disconnesione(socket);
};
socket.OnMessage = message =>
{
SocketService.Messaggio(message, socket);
};
});
This is SocketService.Start():
public static void start()
{
server = new WebSocketServer($"wss://{GetLocalIPAddress()}:{"4450"}/BNS/");
}
I have tried with a simple HTML/JS page using unsecure ws and it worked fine.
Then I have tried in my main program which i need it to be run on HTTPS so when using unsecure ws chrome told me to use wss instead.
So i change my ws server to wss but then it does nothing, it gives me timeout error.
This is the JS code:
var start = function () {
var wsImpl = window.WebSocket || window.MozWebSocket;
var form = document.getElementById('sendForm');
var input = document.getElementById('sendText');
alert("Connessione...");
// create a new websocket and connect
window.ws = new wsImpl('#Percorsi.IndirizzoSocket');
alert("conn");
// when the connection is established, this method is called
ws.onopen = function () {
alert("Connessione aperta");
var openJson = {
"Id": "#Model.accountCorrente.Id",
"type": "Identificazione"
};
alert("send");
ws.send(stringify(openJson));
};
// when the connection is closed, this method is called
ws.onclose = function () {
alert("Connessione chiusa");
}
// when data is comming from the server, this metod is called
ws.onmessage = function (val) {
if (confirm("Hai ricevuto un nuovo messaggio!\nPremi ok per visualizzarlo.")) {
window.location("/Annunci/Chat/" + val);
} else { }
};
}
I can't figured out how to make it works.
Thanks in advance for your help!
It seems like you are not setting the server certificate to be used under WS over TLS (not to be confused with HTTPS which is HTTP over TLS).
If you see the example in fleck's webpage, you will realize that you have to set the Certificate:
server.Certificate = new X509Certificate2("MyCert.pfx");

JavaScript issue with import/export modules and Globally defined variables

(note, I'm using Node.js to create a telnet server and handle user input)
I'm having issues using variables/arrays in javascript inside functions in other scripts.
Let me set a simpler example:
var connections = []
is an array in my main.js
Broadcast.js is a function I put in a separate module and attempt to use the broadcast() function in my main.js.
The error I get is stating that connections is undefined. How do get Broadcast.js able to see the connections array in the main.js
~~
For example in my main.js I set an array to handle clients connecting to a server
//point to Telnet library
const Telnet = require('ranvier-telnet');
const logger = require('./logger.js')
var outspeak = []
var connections = []
var clients = []
let server = new Telnet.TelnetServer(rawSocket => {
let telnetSocket = new Telnet.TelnetSocket();
//attaching socket
telnetSocket.attach(rawSocket);
//setting telnet options
telnetSocket.telnetCommand(Telnet.Sequences.WILL, Telnet.Options.OPT_EOR);
//giving clients a name
telnetSocket.name = rawSocket.remoteAddress + ":" + rawSocket.remotePort
//pushing client names to array
clients.push(telnetSocket.name);
//pushing client connections to an array
connections.push(rawSocket);
console.log(`${telnetSocket.name} has connected`)
logger(`${telnetSocket.name} has connected`)
broadcast(telnetSocket.name + " connected.")
telnetSocket.on('data', function (data) {
//broadcast (telnetSocket.name + ">" + data, telnetSocket);
}
function broadcast (message, sender) {
connections.forEach(function (connection) {
//don't want to send it to sender
if (connection === sender) return;
connection.write(`${message} \n`);
});
}
Now inside my main script, I could called that array/push to that array, read from that array, as long as I type out the function inside the main.js file.
And it can easily use the broadcast function.
Now I want to make it more advance and make reduce my lines on my main.js
but once I separate the broadcast function into it's own module.
use strict'
//broadcast function
function broadcast (message, sender) {
connections.forEach(function (connection) {
//don't want to send it to sender
if (connection === sender) return;
connection.write(`${message} \n`);
});
}
module.exports = broadcast
I get a connection undefined error any time I try to invoke that broadcast function. It's like my global variable/array can't be seen by broadcast.js function.
this is how I'm invoking it
// handle input
telnetSocket.on('data', function (data) {
broadcast (telnetSocket.name + ">" + data, telnetSocket);
});
And yes, const broadcast = require('./broadcast.js'); as been added to the file at the top.
Here's the broken code complete:
'use strict'
//point to Telnet library
const Telnet = require('ranvier-telnet');
const logger = require('./logger.js');
const broadcast = require('./broadcast.js');
var connections = []
var clients = []
//had to call message as global variable
//Asan's timestamp functionm
//telnetstuff
console.log("Starting...");
let server = new Telnet.TelnetServer(rawSocket => {
let telnetSocket = new Telnet.TelnetSocket();
//attaching socket
telnetSocket.attach(rawSocket);
//setting telnet options
telnetSocket.telnetCommand(Telnet.Sequences.WILL, Telnet.Options.OPT_EOR);
//giving clients a name
telnetSocket.name = rawSocket.remoteAddress + ":" + rawSocket.remotePort
//pushing client names to array
clients.push(telnetSocket.name);
//pushing client connections to an array
connections.push(rawSocket);
console.log(`${telnetSocket.name} has connected`)
logger(`${telnetSocket.name} has connected`)
broadcast(telnetSocket.name + " connected.")
// handle input
telnetSocket.on('data', function (data) {
broadcast (telnetSocket.name + ">" + data, telnetSocket);
});
//removing client/connection from array
rawSocket.on('end', function () {
clients.splice(clients.indexOf(telnetSocket), 1);
connections.splice(connections.indexOf(rawSocket), 1);
broadcast(telnetSocket.name + " has left.\n");
logger(telnetSocket.name + " has left.");
console.log(telnetSocket.name + " has left.");
});
}).netServer
server.listen(4000);
console.log('ServerRunning...');
logger('>Server started.');
What I'm missing here? Also I apologize in advance this is my first question ever asked and I've gone through as much I could today to even figure out how to ask my question, maybe I'm not using correct lingo/terms? any help is appreciative.
refactor\broadcast.js:5
connections.forEach(function (connection) {
^
ReferenceError: connections is not defined
In nodejs, when you declare a variable not inside any function definitions, it is scoped to the file only. (This is different from browser javascript.) If you want something to be accessible from outside, you need to export it:
module.exports.connections = connections;
Then import it into the other file:
const connections = require(myFile);
This will work as long as you don't try to set the value of the variable in either file, but if you do that they'll end up pointing to separate objects. But mutating it, calling methods on it, etc should work fine.

Javascript Socket.IO - Socket empty when passing to other object

I'm trying to give the socket object to my 'ConnectionHandler' class, but when using this socket object it gives this error: 'cannot read property socket of undefined socket.io'.
Server class:
Server.prototype.handleConnections = function ()
{
this.queueTime = 15; // Queue time in seconds
var that = this; // Create a global variable of the server object
// On incoming connection
this.io.on('connection', function (socket) {
console.log('connection incoming...'); // Log a message to the server console
// When a client tries to join the queue
socket.on('client_join_queue', function (username) {
// Check if the username is valid
if (! (username.length < 3)) {
var newPlayer = new player(username);
var connectionHandler = new connectionHandling(socket, that, newPlayer);
that.connections.push(connectionHandler);
}
});
});
}
ConnectionHandler class:
'use strict';
var ConnectionHandler = function (_socket, _server, _player)
{
this.socket = _socket;
this.server = _server;
this.player = _player;
this.server.queueHandler.addPlayer(this.player);
this.server.connections[0].socket.emit('player_joined_queue', this.player, this.server.queueHandler.getQueue().length);
var that = this;
socket.on('disconnect', function () {
console.log("user disconnected");
console.log("queue:", that.server.queueHandler.getQueue());
});
}
module.exports.ConnectionHandler = ConnectionHandler;
I've absolutely no idea what I'm doing wrong.
What fljs was saying, you are emitting an event called 'player_joined_queue'.
But you are listening for the event 'client_join_queue'. You need to listen for the event with the same name you are emitting. So you would need to change one or the other. for example,
socket.on('player_joined_queue', function (username) {
...

how to prevent new connection on every page refresh in sockjs

So, every time I refresh the page, it seems like sockjs is creating a new connection.
I am saving every message to my mongodb on every channel.onmessage, so if I refresh my page 7 times and send a message, I would save 7 messages of the same content into my mongodb.
This is very problematic because when I retrieve those messages when I go into the chat room, to see the log, I would see bunch of duplicate messages.
I want to keep track of all connections that are 'active', and if a user tries to make another connection, I want to terminate the old one so there is only one connection listening to each message at a time.
How do I do this ?
var connections = {};
//creating the sockjs server
var chat = sockjs.createServer();
//installing handlers for sockjs server instance, with the same url as client
chat.installHandlers(server, {prefix:'/chat/private'});
var multiplexer = new multiplexServer.MultiplexServer(chat);
var configChannel = function (channelId, userId, userName){
var channel = multiplexer.registerChannel(channelId);
channel.on('connection', function (conn) {
// console.log('connection');
console.log(connections);
connections[channelId] = connections[channelId] || {};
if (connections[channelId][userId]) {
//want to close the extra connection
} else {
connections[channelId][userId] = conn;
}
// }
// if (channels[channelId][userId]) {
// conn = channels[channelId][userId];
// } else {
// channels[channelId][userId] = conn;
// }
// console.log('accessing channel! ', channels[channelId]);
conn.on('new user', function (data, message) {
console.log('new user! ', data, message);
});
// var number = connections.length;
conn.on('data', function(message) {
var messageObj = JSON.parse(message);
handler.saveMessage(messageObj.channelId, messageObj.user, messageObj.message);
console.log('received the message, ', messageObj.message);
conn.write(JSON.stringify({channelId: messageObj.channelId, user: messageObj.user, message: messageObj.message }));
});
conn.on('close', function() {
conn.write(userName + ' has disconnected');
});
});
return channel;
};
The way I resolve a problem like yours was with a Closure and Promises, I don't know if that could help you. I let you the code that help me, this is with EventBus from Vertx:
window.Events = (function NewEvents() {
var eventBusUrl = $('#eventBusUrl').val();
var eventBus = null;
return new RSVP.Promise(function(resolve, reject) {
if(!eventBus) {
eventBus = new vertx.EventBus(eventBusUrl);
eventBus.onopen = function eventBusOpened() {
console.log('Event bus online');
resolve(eventBus);
}
eventBus.onclose = function() {
eventBus = null;
};
}
});
}());
And then in other script I call it in this way:
Events.then(function(eventBus) {
console.log("registering handlers for comments");
eventBus.registerHandler(address, function(incomingMessage) {
console.log(incomingMessage);
});
});
I hope this can help you.
Regards.

calling a socket inside another socket using node.js and socket.io

I am a trying to use socket.io and node.js like this :
The browser sends an event to socket.io, in the data event I call another server to get some data, and I would like to send back a message to the browser using a socket.emit.
This looks like that :
socket.on('ask:refresh', function (socket) {
const net = require("net");
var response = new net.Socket();
response.setTimeout(1000);
response.get_response = function (command, port, host) {
this.connect(port, host, function () {
console.log("Client: Connected to server");
});
this.write(JSON.stringify({ "command": command }))
console.log("Data to server: %s", command);
};
response.on("data", function (data) {
var ret = data.toString();
var tmp_data = JSON.parse(ret.substring(0, ret.length - 1).toString());
var data = new Object();
var date = new Date(tmp_data.STATUS[0].When * 1000 );
data.date = date.toString();
socket.emit('send:refresh', JSON.stringify(data) );
});
response.get_response("version", port, host);
});
};
The thing is that I cannot access "socket.emit" inside response.on.
Could you please explain me how I can put a hand on this ?
Thanks a lot
You appear to be overwriting the actual socket with the one of the callback parameters:
socket.on('ask:refresh', function(socket) {
// socket is different
});
Change the name of your callback variable, and you won't have this problem.

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