I have a Node/Vue application. I am consuming a WebSocket from Binance, a crypto exchange. I can see the quotes on the server console as I log them, I can send them to the browser for a short period of time before the client stops logging them.
Browser just using WebSocket API
Node using ws library
Node code, this I am running as it's own service as its just this.
'use strict';
const WebSocket = require('ws');
const binanceWS = new WebSocket('wss://stream.binance.com:9443/ws/btcusdt#trade')
const server = new WebSocket.Server({ port: 5002 });
//websocket connection event will return a socket you can later use
binanceWS.on("open", function() {
console.log("connected to Binance");
});
binanceWS.on('message', function(data){
console.log(data);
server.on('connection', function connection(ws){
console.log("Connected a new client");
ws.send(data);
});
server.on('closed', function (id){
console.log("connection closed");
console.log(id);
});
server.on('error', function (err){
console.log(err)
})
})
On the Client side I am using Vue and in the app.js file I have this on the created hook.
let socket = new WebSocket("ws://localhost:5002")
socket.addEventListener('message', function(event){
let quotes = JSON.parse(event.data);
console.log(quotes.p)
});
socket.addEventListener('error', function(event){
console.log("closing because " + event);
})
Right now I am only listening to the consoles in the above app.vue file.
What I see in the browser console is a lot of quotes, then they stop after a second or 2. There can be over a thousand quotes in some times. Then on occasion I see a console.log('created') that I have in a child component of app.vue. In many cases this is the last thing in the console after hundreds of quotes.
In the console.log for the server I see a lot of sessions being created with one page refresh. So much that it fills my console.
So I'm not sure I am creating the connections correcly, I am not sure if Vue is somehow stopping the console.log's?
I don't see any errors anywhere and the entire time in my server console the Binance API continues streaming.
you have to write server event listener outside binance on message handler;
then you can pass messages from binance to the server by emitting new event to the server
on receiving message from binance you can send data to all connection on the server
Or Try this code I think it will work :
'use strict';
const WebSocket = require('ws');
const binanceWS = new WebSocket('wss://stream.binance.com:9443/ws/btcusdt#trade')
const server = new WebSocket.Server({ port: 5002 });
server.on('connection', function connection(ws){
console.log("Connected a new client");
});
server.on('closed', function (id){
console.log("connection closed");
console.log(id);
});
server.on('error', function (err){
console.log(err)
})
//websocket connection event will return a socket you can later use
binanceWS.on("open", function() {
console.log("connected to Binance");
});
binanceWS.on('message', function(data){
console.log(data);
server.clients.forEach(function each(client) {
if (client.readyState === WebSocket.OPEN) {
client.send(data);
}
});
})
Related
I built a Socket.io server which handle connection and event :
import { createServer } from "http";
import { Server } from "socket.io";
const httpServer = createServer();
const io = new Server(httpServer);
io.on("connection", (socket) => {
console.log('New connection');
socket.on('join', data => {
console.log(data);
});
...
});
I'm trying to built a Socker.io client using npm module socket.io-client
import { io } from 'socket.io-client';
const socket = io(servHost);
socket.on('connect', () => {
console.log(`Connected : ${socket.id}`);
socket.emit('join', "Some data");
socket.emit('otherEvent');
});
socket.on('disconnect', (err) => {
console.log(err);
console.log("Disconnected");
});
Server log :
New connection
New connection
...
Client log :
Connected : IyR4Gr0Gvao16UD6AAAD
parse error
Disconnected
Connected : m8aSe6HI67i6VIBNAAAF
parse error
Disconnected
...
Note : If I comment socket.emit('join', "Some data"); everything works fine, even the otherEvent is emited and client can handle the expected event in return (not shown on the code). So I guess the error comes from the data inside join event.
some data can be string / array or object (I tried everything) I have the same error.
I'm using :
"socket.io": "^4.5.2",
"socket.io-client": "^4.5.2"
Looks like .emit() expects object as 2nd argument.
I had exactly the same issue, fixed by passing an object:
socket.emit('join', {text: "Some data"});
I've started a project that requires communication between an arduino and a local nodejs server (unrelated the data will be sent via an http request or a socket to the actual remote server later on). I'm using the node package serialport. At the beginning of the serial communication, the server needs to "find" the arduino. I've decided on the following negotiation codex:
1) the server sends a "c" character (as in connect) which the arduino is listening for
2) the arduino replies to all "c"s with another "c" which the server will be listening for
in other words when both sides receive a "c" that means the serial connection works
However, due to serialport using promises I can't go through all available ports and check if there's an arduino (which replies with "c") there.
Here's what I've come up with so far:
var SerialPort = require('serialport');
var Readline = require('#serialport/parser-readline');
async function tryPort(path) {
var port = new SerialPort(path, {
baudRate: 9600
});
port.on('error', function (err) {
console.log(err);
});
port.pipe(new Readline({ delimiter: '\n' })).on('data', (data)=>{
console.log(port);
console.log(data);
if (data == 'c') {
return port;
}
port.close();
});
port.write("c", function (err) {
if (err) console.log(err);
});
}
async function connect() {
var connection, ports = await SerialPort.list();
for(i=0;i<ports.length;i++){
connection = await tryPort(ports[i].path);
}
setTimeout(() => {
if (!connection) {
console.log("no port/response found");
}else{
console.log(connection);
}
}, 3000);
}
connect();
I went with the assumption the variable 'connection' will be assigned the value of the port that responded correctly last because that port will take the longest to finish. Unfortunately, it seems this won't work with promises... So I'm wondering if there's any other way to accomplish it?
I tried to build a chat box server by node.js. When the browser requestes the page, it workes well at first. But when I refresh the page, the Server crashes.
Below is the error message:
events.js:183
throw er; // Unhandled 'error' event
^
Error: read ECONNRESET
at _errnoException (util.js:1022:11)
at TCP.onread (net.js:615:25)
I used the node --inspect index.js, but could not find the point.
Below is the code of index.js:
const http = require('http');
const fs = require('fs');
const extract = require('./extract');
const wss = require('./websockets-server');
var handleError = function (err,res) {
res.writeHead(404);
res.end();
}
var server = http.createServer(function (req, res) {
console.log("Responding to a request.");
var filePath = extract(req.url);
console.log("filePath:"+filePath);
fs.readFile(filePath,function (err,data) {
if(err){
handleError(err,res);
return;
}else {
res.end(data);
}
})
})
server.listen(3000);
When I comment the 4th line, the import of websockets-server. Server works well when I refresh the page. Maybe it's about the websocket while it works without websocket.
Below is code of websockets-server.js:
const WebSocket = require('ws');
var WebSocketServer = WebSocket.Server;
var port = 3001;
var ws = new WebSocketServer({
port:port
});
var message = [];
console.log('websockets server started');
ws.on('connection', function (socket) {
console.log('client connection established');
message.forEach(function (msg) {
socket.send(msg);
})
socket.on('message', function (data) {
console.log('message received: ' + data);
message.push(data);
ws.clients.forEach(function (clientSocket) {
clientSocket.send(data);
});
});
});
Does the problem is about the websocket? Whether should I do process when the client shutdown the connection with the server while refreshing the page.
extract.js below:
const path = require('path');
var extractFilePath = function (url) {
var filePath;
var fileName = 'index.html';
if(url.length > 1){
fileName = url.substring(1);
}
console.log('The fileName is: ' + fileName);
filePath = path.resolve(__dirname, 'app', fileName);
return filePath;
}
module.exports = extractFilePath;
I guess that you maybe execute var ws = new WebSocket("ws://localhost:3001"); in html file. I haven't figured out exact reason about your error as I'm not proficient in WebSocket. But there is a solution:
window.onbeforeunload = function () {
ws.close();
}
close connection before reload, then the error will not reappear.
You need to add an error listener on the socket. Error listener only on the websocket instance does not help in this case.
socket.on('error', function(e){
console.log(e);
});
The ECONNRESET error means that the other side (browser) closed the connection abruptly. On browser refresh, browser simple killed the connection with the websocket server.
To solve this, you have to listen for the error event on the websocket server instance.
// listen for "error" event so that the whole app doesn't crash
wss.on("error", function(error){
console.log(error);
}
I was having the same problem, but it resolved after this command:
npm install #ionic/app-scripts#nightly --save-dev
I have a use case where I need to take input from browser pass it to my node server over a socket, this input is then send to a third party website for processing again over socket. The result received from the third party website needs to be sent back to browser.
node server
var express = require('express');
var app = express();
var server = require('http').createServer(app);
var socketIO = require('socket.io'),
server, io;
var thirdPartSocketClient = require('socket.io-client');
//Custom imports
var thirdParty = require('./ms_socket.js');
var socket = socketIO(server);
socket.on('connection', function(client) {
var token = null;
//Token from third party site that we should have before sending the actual info
thirdParty.getToken(function callback(returnToken) {
token = returnToken;
});
thirdPartSocketClient = thirdParty.getTranslation(token);
client.on('audio', function(data) {
thirdPartSocketClient.emit(data);
});
});
server.listen(8080, function() {
console.log('Open http://localhost:8080 in your browser');
});
ms_socket.js
//Exported function making a socket call to third party service
var exports = module.exports = {};
var request = require('request');
var wsClient = require('socket.io-client');
var fs = require('fs');
exports.getToken = function(callback) {
//send back the token
}
exports.getTranslation = function(accessToken) {
var ws = new wsClient(thirdPartySocketURL);
// event for connection failure
ws.on('connectFailed', function(error) {
console.log('Initial connection failed: ' + error.toString());
});
// event for connection succeed
ws.on('connect', function(connection) {
console.log('Websocket client connected');
// process message that is returned
//processMessage would process the incoming msg from third party service
connection.on('message', processMessage);
connection.on('close', function(reasonCode, description) {
console.log('Connection closed: ' + reasonCode);
});
// print out the error
connection.on('error', function(error) {
console.log('Connection error: ' + error.toString());
});
});
// connect to the service
ws.connect(thirdPartySocketURL, null, null, {
'Authorization': 'Bearer ' + accessToken
});
return ws;
}; //End of export function
I am able to receive the data from browser, make a connection to third party service (can see the socket connection) and emit the data. however I am unable to receive the reply back from the third part service.
Is it because node is not listening to my socket events of thirdparty ?
Not sure exactly why its not working.
I save the data locally on the server, read the file and then send it, then I get a response back from the service.
If this is not a "right" design can you please suggest a good way, should I be using message queues (if yes, feel free to recommend one)
Thanks
I think what I need to do is reset Socket.io entirely after each test using socket.io.
Any ideas? Here's what I'm doing:
I have a test using Socket.IO's Client library, an angular service (github.com/chrisenytc/ng-socket), requireJS, and a local test server. When using karma's watch feature, it runs fine the first time, but fails subsequent attempts (event listeners aren't triggered, debug logging shows an 'xhr poll error').
the simple version of the test is (full version):
define(['services/serviceModule', 'angular-mocks'], function() {
describe('ILC Server Services', function() {
var socket;
beforeEach(module('ignisLibriColloqui.services', function(Config, $socketProvider) {
$socketProvider.setUrl(Config.ilcTestServerUrl);
Config.ilcServerUrl = Config.ilcTestServerUrl;
url = Config.ilcTestServerUrl;
}));
beforeEach(inject(function(ILCServerService, $socket) {
ilcServerService = ILCServerService;
socket = $socket;
}));
it('expects emit(\'ping\') to trigger on(\'pong\')', function(done) {
socket.emit('ping',{})
socket.on('pong',function(data) {
done();
});
});
});
});
and the simple server is (full version)
var httpPort = 10999;
var socketPort = 5001;
var restify = require('restify');
var socketio = require('socket.io')(socketPort);
var fs = require('fs');
var server = restify.createServer({
name: 'ilcServer Mock'
});
var io = socketio.listen(server);
server.get(/.*/, restify.serveStatic({
'directory': __dirname,
'default': './app/index.html',
'maxAge': 0
}));
io.sockets.on('connection', function(socket) {
var socketId = socket.id;
console.log('user connected');
socket.on('ping', function(data) {
console.log('ping');
socket.emit('pong', data);
});
socket.on('disconnect',function() {
console.log('disconnect');
socket.disconnect();
});
});
server.listen(httpPort, function() {
console.log('restify server listening at %s', server.url, 'socket port:', socketPort);
});
Edit
After carefully exploring the connections using the logging described by the Socket.io docs it has become clear to me that disconnecting the client is not enough. The client logs the "pong" events without firing the socket.on('pong',event), even when using an afterEach to cause socket.disconnect() and socket.io.connect(function(){done()}) to trigger, the new calls to socket.emit are not triggered.