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How to handle Error: socket hang up while waiting Node and React

I've been working on a NodeJS express route the accepts a get request, counts and analyzes about 15000+ data, so from my react app (Axios) when I hit the get URL, the processing and analyzing takes more than 4 to 5 min and the socket hangs up on about 2min what should I do to make my react app wait longer or get a response in any other way. Maybe an HTTP 202 has its way but I don't know how to do it, Any Help?

the wise choice is to use websocket or socket-io for such use cases.
but you can also :
use express timeout . to keep the connection alive between the client and the server:
first, install :
npm install connect-timeout
after that change your server entry point(app.js) file.
var express = require('express')
var timeout = require('connect-timeout')
// example of using this top-level; note the use of haltOnTimedout
// after every middleware; it will stop the request flow on a timeout
var app = express()
app.use(timeout('400s'))
app.use(haltOnTimedout)
// Add your routes here, etc.
function haltOnTimedout (req, res, next) {
if (!req.timedout) next()
}
app.listen(3000)
for more details : express official
or if you don't want to install any third-party module :
app.use(function(req, res, next){
res.setTimeout(120000, function(){
console.log('Request has timed out.');
res.send(408);
});
next();
});

UnhandledPromiseRejectionWarning Error: Slash in host identifier

I am trying to run nodemon index.js in my terminal but I am getting the following error which I have absolutely no idea what it means as for me is very unclear.
Can please anyone explain to me how to solve this?
index.js
const express = require('express');
const morgan = require('morgan');
const bodyParser = require('body-parser');
const mongoose = require('mongoose');
var app = express();
var router = require('./services/router');
mongoose.connect('mongodb://localhost:apiAuth');
app.use(morgan('combined'));
app.use(bodyParser.json());
app.use('/v1', router);
var PORT = process.env.PORT || 3000;
var HOST = process.env.HOST || '127.0.0.1';
console.log('Listening on', HOST, PORT);
app.listen(PORT, HOST);
services/router.js
var router = require('express').Router();
function protected(req, res, next) {
res.send('Here is the secret!');
}
router.route('/protected')
.get(protected);
module.exports = router;
Terminal
[nodemon] restarting due to changes...
[nodemon] restarting due to changes...
[nodemon] starting `node index.js`
Listening on 127.0.0.1 3000
(node:29104) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 2): Error: Slash in host identifier
(node:29104) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

The problem comes from your connection to MongoDB via Mongoose.
Short version :
You have entered a bad login URL:
mongoose.connect('mongodb://localhost:apiAuth');
^^^^^^^
I think you want to write (or something close to it):
mongoose.connect('mongodb://localhost:'+apiAuth);
Here's an example of a MongoDB login URL : mongodb://127.0.0.1:27017/my_db.
Or the doc: Standard Connection String Format
Long version :
The resolution of the problem is the same as above, but you would have located it yourself.
For my part, I proceeded like that (because I had exactly the same problem, with as much information).
Isolate the code that generates the error: You can simply comment on parts of your code to determine which zone is crashing.
Add a catch() after the connection with Mongoose: mongoose.connect(...).catch((e) => { console.log(e); throw e; }. This will have indicated directly the line concerned and some additional information.
This kind of technique works in a lot of cases.

I also have same error as like above (Error: Slash in host identifier). I resolved the issue. I am accessing mongooses as like below. My database password contains # so here is the problem when our password having # special character we need to pass with the help of encodeURIComponent. I passed the user name and password as like below its working fine for me.
Error:
mongoose.connect('mongodb://xxx-xx:7a?VNXd##sabfpV8=gRLwnNvC_8#196.89.12.168:27017/xxxxx',function(err,db){
if(err){
console.log(err);
}else {
console.log('connected to the Test db');
}
});
Resolved code:
mongoose.connect('mongodb://xxx-xx:'+encodeURIComponent("7a?VNXd###safpV8=gRLwnNvC_8")+'#196.89.12.168:27017/xxxxx',function(err,db){
if(err){
console.log(err);
}else {
console.log('connected to the Test db');
}
});

I was facing similar error, what i did is
Previous Error Causing Version:
mongoose.connect("mongodb://localhost:cat_app");
Working Version
mongoose.connect("mongodb://localhost/cat_app");
Both are same except : is replaced with /

Node.js - Auto Refresh In Dev

I am trying to improve the DEV experience in my Node. To do that, I want to:
a) restart my server when server-side code is changed
b) refresh the browser when client-side code is changes. In an effort to accomplish this, I began integrating nodemon and browserSync into my gulp script.
In my gulp script, I have the following task:
gulp.task('startDevEnv', function(done) {
// Begin watching for server-side file changes
nodemon(
{ script: input.server, ignore:[input.views] })
.on('start', function () {
browserSync.init({
proxy: "http://localhost:3002"
});
})
;
// Begin watching client-side file changes
gulp.watch([ input.css, input.js, input.html ], function() { browserSync.reload(); });
done();
});
When the above task runs, my browser opens to http://localhost:3000/. My app is visible as expected. However, in the console window, I notice:
Error: listen EADDRINUSE :::3002
I understand to some extend. I have app.set('port', process.env.PORT || 3002); in my server.js file. Yet, I thought that was purpose of setting the proxy value. Still, whenever I make a code change, I see the following related error in my console window:
[07:08:19] [nodemon] restarting due to changes...
[07:08:19] [nodemon] starting `node ./dist/server.js`
events.js:142
throw er; // Unhandled 'error' event
^
TypeError: args.cb is not a function
at Object.init (/Users/me/Website/Develop/node_modules/browser-sync/lib/public/init.js:25:25)
at null.<anonymous> (/Users/me/Website/Develop/gulpfile.js:142:25)
at emitNone (events.js:73:20)
at emit (events.js:167:7)
at Object.run (/Users/me/Website/Develop/node_modules/nodemon/lib/monitor/run.js:97:7)
at Function.run.kill (/Users/me/Website/Develop/node_modules/nodemon/lib/monitor/run.js:221:7)
at null.<anonymous> (/Users/me/Website/Develop/node_modules/nodemon/lib/monitor/run.js:333:7)
at emitOne (events.js:83:20)
at emit (events.js:170:7)
at restartBus (/Users/me/Website/Develop/node_modules/nodemon/lib/monitor/watch.js:162:7)
Me-MBP:Develop me$ events.js:142
throw er; // Unhandled 'error' event
^
Error: listen EADDRINUSE :::3002
at Object.exports._errnoException (util.js:856:11)
at exports._exceptionWithHostPort (util.js:879:20)
at Server._listen2 (net.js:1238:14)
at listen (net.js:1274:10)
at Server.listen (net.js:1370:5)
at Object.<anonymous> (/Users/me/Website/Develop/dist/server.js:70:8)
at Module._compile (module.js:399:26)
at Object.Module._extensions..js (module.js:406:10)
at Module.load (module.js:345:32)
at Function.Module._load (module.js:302:12)
At this point, my code changes do not appear in my browser. I do not understand what I'm doing wrong. I suspect I have my ports misconfigured. But, I'm not really sure how they should be setup.
By default BrowserSync uses port 3000. BrowserSync also uses port 3001 for the BrowserSync UI. For these two reasons, I thought I would set the port to 3002 in my server.js file and create the proxy shown above. What am I doing wrong?

You actually don't need to use gulp for this to work.
a) restart my server when server-side code is changed
Install nodemon globally using npm i -g nodemon then on your app folder do nodemon or nodemon ${index-file-of-your-app}.
b) refresh the browser when client-side code is changes.
Use browserify or webpack. I prefer using webpack; you may need to learn about the configuration a little bit but the good thing with webpack is that you don't need to refresh it. Once changes are found the changes will be reflected on the browser automatically. https://github.com/webpack/docs/wiki/hot-module-replacement-with-webpack

You can livereload both front and backend changes to the browser by using the 'livereload', 'connect-livereload', and 'nodemon' packages together. Also, this way you don't need Gulp or Grunt. Here's how the packages play together:
livereload opens a high port and notifies the browser of changed public files
connect-livereload monkey patches every served HTML page with a snippet that connects to this high port
nodemon is then used to restart the server on changed backend files
Set up livereload in Express
Set up the Express to both start livereload server watching the public directory and ping the browser during nodemon-induced restart:
const livereload = require("livereload");
const connectLivereload = require("connect-livereload");
// open livereload high port and start to watch public directory for changes
const liveReloadServer = livereload.createServer();
liveReloadServer.watch(path.join(__dirname, 'public'));
// ping browser on Express boot, once browser has reconnected and handshaken
liveReloadServer.server.once("connection", () => {
setTimeout(() => {
liveReloadServer.refresh("/");
}, 100);
});
const app = express();
// monkey patch every served HTML so they know of changes
app.use(connectLivereload());
Start Express with nodemon
Then you'd start the server with nodemon, for example, with a dedicated watch script by running npm run watch.
The key point here is to ignore the public directory that's already being watched by livereload. You can also configure files with non-default extensions, like pug and mustache, to be watched.
"scripts": {
"start": "node ./bin/www",
"watch": "nodemon --ext js,pug --ignore public"
},
You can read a longer explanation in "Refresh front and backend changes to browser with Express, LiveReload and Nodemon."

#mateeyow is right.
But if you want the browser to reload automaticaly, you also need livereload-plugin.
Enable webpack-hot-replacement only replace code in browser's memory, livereload-plugin do reload it.
See rock for example: https://github.com/orange727/rock/blob/master/app/templates/webpack/webpack.make.js#L255
Just as:
webpackConfig.plugins: [
new webpack.HotModuleReplacementPlugin(),
new LiveReloadPlugin({
appendScriptTag: true,
port: config.ports.livereload,
})];

I might be missing some context (e.g. I'm not sure what input represents), however, I think the npm module reload might solve your problem. Here's an example from the npm package page:
var express = require('express')
, http = require('http')
, path = require('path')
, reload = require('reload')
, bodyParser = require('body-parser')
, logger = require('morgan')
var app = express()
var publicDir = path.join(__dirname, '')
app.set('port', process.env.PORT || 3000)
app.use(logger('dev'))
app.use(bodyParser.json()) //parses json, multi-part (file), url-encoded
app.get('/', function(req, res) {
res.sendFile(path.join(publicDir, 'index.html'))
})
var server = http.createServer(app)
//reload code here
//optional reload delay and wait argument can be given to reload, refer to [API](https://github.com/jprichardson/reload#api) below
reload(server, app, [reloadDelay], [wait])
server.listen(app.get('port'), function(){
console.log("Web server listening on port " + app.get('port'));
});

The EADDRINUSE error is normally due to a connection already open on the specified port. This is probably due to a previous instance of the connection not being correctly closed when restarting the app.
Take a look at this gist and in particular try something like this in your gulp file:
'use strict';
var gulp = require('gulp');
var browserSync = require('browser-sync');
var nodemon = require('gulp-nodemon');
gulp.task('default', ['browser-sync'], function () {});
gulp.task('browser-sync', ['nodemon'], function() {
browserSync.init(null, {
proxy: "http://localhost:3002"
});
});
gulp.task('nodemon', function (cb) {
var started = false;
return nodemon({
script: 'app.js'
}).on('start', function () {
// to avoid nodemon being started multiple times
if (!started) {
cb();
started = true;
}
});
});

node.js Error: connect ECONNREFUSED; response from server

I have a problem with this little program:
var http = require("http");
var request = http.request({
hostname: "localhost",
port: 8000,
path: "/",
method: "GET"
}, function(response) {
var statusCode = response.statusCode;
var headers = response.headers;
var statusLine = "HTTP/" + response.httpVersion + " " +statusCode + " " + http.STATUS_CODES[statusCode];
console.log(statusLine);
for (header in headers) {
console.log(header + ": " + headers[header]);
}
console.log();
response.setEncoding("utf8");
response.on("data", function(data) {
process.stdout.write(data);
});
response.on("end", function() {
console.log();
});
});
The result in console is this:
events.js:141
throw er; // Unhandled 'error' event
^
Error: connect ECONNREFUSED 127.0.0.1:8000
at Object.exports._errnoException (util.js:870:11)
at exports._exceptionWithHostPort (util.js:893:20)
at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1063:14)
I do not understand why this happens.

From your code, It looks like your file contains code that makes get request to localhost (127.0.0.1:8000).
The problem might be you have not created server on your local machine which listens to port 8000.
For that you have to set up server on localhost which can serve your request.
Create server.js
var express = require('express');
var app = express();
app.get('/', function (req, res) {
res.send('Hello World!'); // This will serve your request to '/'.
});
app.listen(8000, function () {
console.log('Example app listening on port 8000!');
});
Run server.js : node server.js
Run file that contains code to make request.

Please use [::1] instead of localhost, and make sure that the port is correct, and put the port inside the link.
const request = require('request');
let json = {
"id": id,
"filename": filename
};
let options = {
uri: "http://[::1]:8000" + constants.PATH_TO_API,
// port:443,
method: 'POST',
json: json
};
request(options, function (error, response, body) {
if (error) {
console.error("httpRequests : error " + error);
}
if (response) {
let statusCode = response.status_code;
if (callback) {
callback(body);
}
}
});

I solved this problem with redis-server, you can install that like this!
sudo apt-get install redis-server
after that see the port and change it!

I had the same problem on my mac, but in my case, the problem was that I did not run the database (sudo mongod) before; the problem was solved when I first ran the mondo sudod on the console and, once it was done, on another console, the connection to the server ...

Just run the following command in the node project:
npm install
Its worked for me.

i ran the local mysql database, but not in administrator mode, which threw this error

If you have stopped the mongod.exe service from the task manager, you need to restart the service. In my case I stopped the service from task manager and on restart it doesn't automatically started.

I got this error because my AdonisJS server was not running before I ran the test. Running the server first fixed it.

If this is the problem with connecting to the redis server (if your redis.createClient function does not work although you are sure that you have written the right parameters to the related function), just simply type redis-server in another terminal screen. This probably gonna fix the issue.
P.S.: Sorry if this is a duplicate answer but there is no accepted answer, so, I wanted to share my solution too.

This is very slight error. When I was implementing Event server between my processes on nodejs.
Just check for the package you're using to run your server like Axios.
Maybe you might have relocated the files or disconnected some cache data on the browsers.
It's simple ,In your relevant directory run the following command
I was using axios so I used
npm i axios
Restart the server
npm start
This will work.

use a proxy property in your code it should work just fine
const https = require('https');
const request = require('request');
request({
'url':'https://teamtreehouse.com/chalkers.json',
'proxy':'http://xx.xxx.xxx.xx'
},
function (error, response, body) {
if (!error && response.statusCode == 200) {
var data = body;
console.log(data);
}
}
);

"Object is not a function" when passing a Node.js HTTP server object to Socket.IO

This was working a few months ago when I was creating an HTTPS server, but I switched to http (not sure this switch is directly related, just mentioning it in case) today when revisiting this application, where I create a server and pass it to socket.io:
init.js
var server = require(dirPath + "/custom_modules/server").serve(80);
var socket = require(dirPath + "/custom_modules/socket").socket(server);
It is important that I pass the server to socket.io (I know there are alternate ways of initializing the socket) this way because that's how it has to be done in order to encrypt the websocket connection when I switch back to serving HTTPS later.
So my server module:
//serve files
module.exports.serve = function(port) {
//var server = https.createServer(options, function(req, res) { // SSL Disabled
var server = http.createServer(function(req, res) {
// Parse & process URL
var reqInfo = url.parse(req.url, true, true), path = reqInfo.pathname;
// Quickly handle preloaded requests
if (preloaded[path])
preloadReqHandler(req, res, preloaded[path], path);
// Handle general requests
else
generalReqHandler(req, res, reqInfo);
}).listen(port);
return server; //this should be returning an http server object for socket.io
};
and my socket module:
module.exports.socket = function(server) {
//create socket
var socket = require(dirPath + '/node_modules/socket.io')(server);
// ^ error
// .. snip ..
//handle client connection
socket.on("connection", function(client) {
// .. snip ..
});
};
and my error:
/home/ec2-user/Sales_Freak/server/custom_modules/socket.js:17
var socket = require(dirPath + '/node_modules/socket.io')(server);
^
TypeError: object is not a function
at Object.module.exports.socket (/home/ec2-user/Sales_Freak/server/custom_modules/socket.js:17:59)
at Object.<anonymous> (/home/ec2-user/Sales_Freak/server/init.js:16:59)
Assume all of the necessary Node.JS modules are required properly above. What silly mistake am I making today?

The exported module is not a function, refer to your previous statement:
var socket = require(dirPath + "/custom_modules/socket").socket(server);
And compare that to your current statement:
var socket = require(dirPath + '/node_modules/socket.io')(server);
I think you meant to do this instead.
var socket = require(dirPath + '/node_modules/socket.io').socket(server);

This might or might not be helpful to others, but my problem was that I changed the directory of my Node.js server files and socket.io wasn't installed in the new location.
The module was there in node_modules but not installed. I'm actually not sure how installation works with npm modules, but the module existed and therefore didnt throw an error saying it didnt exist, but did not act like it was really there until I did npm install socket.io
If you get this error in this situation, you forgot install socket.io.