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socket.io application keeps loading

Why does my socket.io webapplication keeps loading, i've implemented auth with certifications, but when i try to access localhost, it keeps loading. ive tried follow this doc, but dosent help:https://socket.io/docs/v3/client-initialization/
i dont get any error.
server.s
'use strict';
// Setup basic express server
var express = require('express');
var app = express();
var port = process.env.PORT || 4000;
var crypto = require('crypto');
var sqlite3 = require('sqlite3').verbose();
var db = new sqlite3.Database('./data/db.sqlite');
const bcrypt = require('bcrypt');
const tls = require('tls');
var validator = require('validator');
// Routing
app.use(express.static(__dirname + '/public'));
app.use(express.json());
// Chatroom
// usernames which are currently connected to the chat
var usernames = {};
var numUsers = 0;
const fs = require("fs");
const server = require("https").createServer({
cert: fs.readFileSync("./server-cert.pem"),
key: fs.readFileSync("./server-key.pem")
});
server.listen(port, function () {
console.log('Server listening at port %d', port);
});
const io = require("socket.io")(server);
io.on('connection', function (socket) {
console.log("works")
}
client.js
const fs = require("fs");
const socket = require("socket.io-client")(4000, {
ca: fs.readFileSync("./server-cert.pem")
});
socket.on("connect_error", (err) => {
console.log(`connect_error due to ${err.message}`);
});

jaeger endpoint isnt recieving data using jaeger Node.js client

Was trying to connect to jaeger using HTTP request using nodejs but the spans are not reaching the jaeger endpoint. please help with this code snippet.,
var initTracer = require('jaeger-client').initTracer;
var config = {
'serviceName': 'servicename1',
'reporter': {
'collectorEndpoint': 'http://jaeger-collector:14268/api/traces',
}
};
var options = {
tags: {
'servicename1': '1.0'
}
};
var tracer = initTracer(config, options);
var express = require('express');
var app = express();
var http = require('http');
var server = http.createServer(app);
app.get('/', (req, res) => {
const span = tracer.startSpan('http_request');
res.send('Hello Jaeger');
span.log({'event': 'request_end'});
span.finish();
});
app.get('/', function(req, res) {
res.send("Hello World!");
});
server.listen(3000);
console.log('Express server started on port %s', server.address().port);
Any help would be much appreciated!

Got it! We need to enable sampling strategy to reach the collector endpoint.
var initTracer = require('jaeger-client').initTracer;
var config = {
'serviceName': 'Jaeger_Service',
'reporter': {
'collectorEndpoint': 'http://jaeger-collector:14268/api/traces',
},
'sampler': {
'type': 'const',
'param' : 0.1
}
};
var options = {
'logger': {
'info': function logInfo(msg) {
console.log('INFO ', msg)
},
'error': function logError(msg) {
console.log('ERROR', msg)
}
}
};
var tracer = initTracer(config, options);
var express = require('express');
var app = express();
var http = require('http');
var server = http.createServer(app);
app.get('/', (req, res) => {
const span = tracer.startSpan('http_request');
res.send('Hello Jaeger');
span.log({'event': 'request_end'});
span.finish();
});
server.listen(8000);
console.log('Express server started on port %s', server.address().port);

communicate between modules nodjs

I have a express module in a file to register username and in another file, socket.io module to create chat. what might be the best way to send username to socket module?
server.js
var express = require('express');
app = express();
var http = require('http').Server(app);
var io = require('socket.io')(http);
var morgan = require('morgan');
var wagner = require('wagner-core');
var bodyParser = require('body-parser');
var port = process.env.PORT || 8080;
var name = [];
app.use(morgan('dev'));
app.use(express.static('public'));
app.use(bodyParser.urlencoded({'extended':'true'})); // parse application/x-www-form-urlencoded
app.use(bodyParser.json()); // parse application/json
app.use(bodyParser.json({ type: 'application/vnd.api+json' })); // parse application/vnd.api+json as json
var dependencies = require("./app/dependencies.js")(wagner);
require('./app/routes.js')(app,wagner);
require('./app/socketio.js')(io,wagner);
http.listen(port,function(){
console.log('listening on *:'+port);
});
./app/routes.js
module.exports = function(app,wagner) {
// api ------------------------------------------------------------------
app.post('/api/user', function(req, res) {
console.log(req.body);
// name.push(req.body.name);
res.json({ message: 'from post' });
wagner.invoke(function (UserName){
UserName = "mjt";
});
});
};
./app/socketio.js
module.exports = function (io,wagner) {
io.on('connection', function(socket){
var userName = wagner.invoke(function(UserName) {
console.log(UserName);
});
console.log('a user connected');
io.emit('user connected', "connected");
socket.on('chat message', function(msg) {
console.log('message: ' + msg);
io.emit('chat message', msg);
});
socket.on('disconnect',function () {
console.log('user disconnect');
io.emit('user disconnected', "disconnected");
});
});
}

Found a way to pass data by making the module singleton, this might not be best solution, but I could achieve what I wanted
./app/socketio.js
var socketio = function () {}
socketio.prototype.users = [];
socketio.prototype.start = function(io){
console.log("from start");
var that = this.users;
var people = {};
io.on('connection', function(socket){
console.log(that);
console.log('a user connected');
io.emit('user connected', "connected");
socket.on('chat message', function(msg) {
console.log('message: ' + msg);
io.emit('chat message', msg);
});
socket.on('disconnect',function () {
console.log('user disconnect');
io.emit('user disconnected', "disconnected");
});
});
}
socketio.prototype.updateUser = function (user) {
console.log(user);
this.users.push(user);
console.log(this.users);
}
module.exports = exports = new socketio();
server.js
var express = require('express');
app = express();
var http = require('http').Server(app);
var io = require('socket.io')(http);
var morgan = require('morgan');
var wagner = require('wagner-core');
var bodyParser = require('body-parser');
var port = process.env.PORT || 8080;
var name = [];
var socketIo = require('./app/socketio.js');
var startio = socketIo.start(io);
socketIo.updateUser("hey");
socketIo.updateUser("there");
app.use(morgan('dev'));
app.use(express.static('public'));
app.use(bodyParser.urlencoded({'extended':'true'})); // parse application/x-www-form-urlencoded
app.use(bodyParser.json()); // parse application/json
app.use(bodyParser.json({ type: 'application/vnd.api+json' })); // parse application/vnd.api+json as json
var dependencies = require("./app/dependencies.js")(wagner);
require('./app/routes.js')(app,wagner,socketIo);
http.listen(port,function(){
console.log('listening on *:'+port);
});
Hope this helps to needed ones like me, please suggest better ways, thanks

express.Createserver() not working

I am beginner to nodejs. I tried below code. But server is not listening to the port and host.
var fs = require("fs");
var config = JSON.parse(fs.readFileSync("config.json"));
var host = config.host;
var port = config.port;
var express = require("express") ,http = require("http");
var app = express();
var server = http.createServer(app);
app.get("/", function(request, response){
response.send("hello");
});
app.listen(port, host);
I also tried below code. But found in SO that this method is deprecated. And I replaced it with above code. Though it is not working. I also tried installing express globally then also not listening to port. What might be the problem.
var express = require("express");
var app = express.createServer();
app.get('/', function(request, response){
response.send("hello");
});
app.listen(port, host);
This is my config file.
[{
"host" : "127.0.0.1",
"port" : 1337
}]

config is array not object, you need to access it accordingly(or change the config) .Here is corrected code;
var fs = require("fs");
var config = JSON.parse(fs.readFileSync("config.json"));
var host = config[0].host;
var port = config[0].port;
var express = require("express") ,http = require("http");
var app = express();
var server = http.createServer(app);
app.get("/", function(request, response){
response.send("hello");
});
var server = http.createServer(app);
app.get("/", function(request, response){
response.send("hello");
});
var server = app.listen(port, host);
server.on('error', function(err) {
console.log('error:' + err);
});
server.on('listening', function(){
console.log('server is up, all is well');
});

Nodejs Publish from Client in pub/sub

I am trying to build a small app in nodejs to publish and subscribe. I am stucked in how I can publish from client side. Here is the code I have.
Here is my server code (server.js)
var express = require('express'),
app = express(),
http = require('http'),
server = http.createServer(app);
app.use(express.bodyParser());
app.get('/', function(req, res) {
res.sendfile(__dirname + '/public/index.html');
});
app.post('/publish/:channel/:event/', function(req, res) {
console.log("**************************************");
var params = req.params;
console.log(req.params);
console.log(req.body);
var data = req.body;
console.log("**************************************");
var result = io.sockets.emit(params.channel,{event:params.event,data:data});
//console.log(result);
console.log("**************************************");
res.sendfile(__dirname + '/public/index.html');
});
//include static files
app.use(express.static(__dirname + '/public'));
server = server.listen(3000);
var io = require('socket.io').listen(server);
io.sockets.on('connection', function (s) {
socket = s
socket.emit('c1', { hello: 'world' });
socket.on('test', function (data) {
socket.emit('c1', { hello: 'world' });
console.log('test');console.log(data);
});
});
And here is client code
var narad = {};
narad.url = 'http://192.168.0.46:3000';
narad.lisentingChannels = {}
var socket = io.connect(narad.url);
function Channel(channelName) {
this.channelName = channelName; //serviceObject is the object of
this.events = {};
};
Channel.prototype.bind = function (event, callback) {
this.events[event] = callback;
};
narad.subscribe = function (channelName) {
var channel = new Channel(channelName)
this.lisentingChannels[channelName] = channel;
socket.on(channelName, this.callbackBuilder(channel))
return this.lisentingChannels[channelName];
}
narad.callbackBuilder = function (channel) {
return function (data) {
var callback = channel.events[data["event"]];
callback(data.data);
}
}

You can use the emit method on both the client and the server websocket connections, taken from Socket.io:
var socket = io.connect(narad.url);
socket.emit('publish', 'message');
Then on your server you listen for the message:
socket.on('publish', function (data) {
// Emit the published message to the subscribers
socket.emit('subscribers', data);
console.log(data);
});
This way you are using the bi-directional communication of websockets without having to use some POST api.