Heroku says : Cannot find module 'socket.io' - node.js

Question

I'm deploying an node.js app with deps/modules like : stylus, express, socket.io on heroku.
The beginning of the server.js
/**
* Bootstrap app.
*/
// I've tried with and without that line... not sure what it does
require.paths.unshift(__dirname + '/../../lib/');
/**
* Module dependencies.
*/
// I've tried with "socket.io", "./socket.io" and "Socket.IO"
var express = require('express')
, stylus = require('stylus')
, nib = require('nib')
, sio = require('socket.io');
The file package.json
{
"name": "test.io" , "description": "blabla" , "version": "0.0.1" , "dependencies": {
"express": "2.3.11"
, "jade": "0.12.1"
, "stylus": "0.13.3"
, "nib": "0.0.8"
} }
So the one and only heroku web worker crash. Here's the log :
2011-10-24T09:15:27+00:00 heroku[slugc]: Slug compilation finished
2011-10-24T09:15:35+00:00 heroku[web.1]: Unidling
2011-10-24T09:15:35+00:00 heroku[web.1]: State changed from down to created
2011-10-24T09:15:35+00:00 heroku[web.1]: State changed from created to starting
2011-10-24T09:15:39+00:00 heroku[web.1]: State changed from starting to crashed
2011-10-24T09:15:39+00:00 heroku[web.1]: State changed from crashed to created
2011-10-24T09:15:39+00:00 heroku[web.1]: State changed from created to starting
2011-10-24T09:15:41+00:00 heroku[web.1]: Starting process with command `node app.js`
2011-10-24T09:15:41+00:00 app[web.1]:
2011-10-24T09:15:41+00:00 app[web.1]: node.js:134
2011-10-24T09:15:41+00:00 app[web.1]: throw e; // process.nextTick error, or 'error' event on first tick
2011-10-24T09:15:41+00:00 app[web.1]: ^
2011-10-24T09:15:41+00:00 app[web.1]: Error: Cannot find module 'socket.io'
2011-10-24T09:15:41+00:00 app[web.1]: at Function._resolveFilename (module.js:320:11)
2011-10-24T09:15:41+00:00 app[web.1]: at Function._load (module.js:266:25)
2011-10-24T09:15:41+00:00 app[web.1]: at require (module.js:348:19)
2011-10-24T09:15:41+00:00 app[web.1]: at Object.<anonymous> (/app/app.js:18:11)
2011-10-24T09:15:41+00:00 app[web.1]: at Module._compile (module.js:404:26)
2011-10-24T09:15:41+00:00 app[web.1]: at Object..js (module.js:410:10)
2011-10-24T09:15:41+00:00 app[web.1]: at Module.load (module.js:336:31)
2011-10-24T09:15:41+00:00 app[web.1]: at Function._load (module.js:297:12)
2011-10-24T09:15:41+00:00 app[web.1]: at Array.<anonymous> (module.js:423:10)
2011-10-24T09:15:41+00:00 app[web.1]: at EventEmitter._tickCallback (node.js:126:26)
2011-10-24T09:15:41+00:00 heroku[web.1]: Process exited
2011-10-24T09:15:44+00:00 heroku[web.1]: State changed from starting to crashed
So, any ideas ? Ever happened to anyone ?

Answer 1

I believe you should add socket.io in dependencies in package.json.
{ "name": "test.io" , "description": "blabla" , "version": "0.0.1" , "dependencies": { "express": "2.3.11" , "jade": "0.12.1" , "stylus": "0.13.3" , "nib": "0.0.8" , "socket.io" : "0.8.5" } }
Or just do this:
npm install socket.io --save
Which will install the latest version of socket.io and add it to the dependencies.

Answer 2

npm install socket.io
did the trick for me. If you are under windows make sure you are running it as administrator.

Answer 3

These are solutions to socket.io related problems
I hope i will work
Ports in your (index.js or server.js) & (index.html and your client.js) port must be different. (refer below code)
=============your index.js file ======================
(port here is 8000)
const express = require("express")
var app = express();
const http = require('http')
var server = http.createServer(app);
const port = process.env.PORT || 8000
server.listen(port,()=>
{
console.log("Listening at port => "+port)
});
var io = require('socket.io')(server, {
cors: {
origin: '*',
}
});
const cors = require("cors")
app.use(cors())
=============your client.js file ======================
port here is 8080
const socket = io.connect('https://localhost:8080/')
=============your index.html file ======================
port here is 8080
<script defer src="https://localhost:8080/socket.io/socket.io.js">
</script>
Remember your "server.js or index.js" port should be different from "client.js" port (Rememeber this is important)
(index.html and your client.js) port must be same
You should always use 'http' while working with socket.io (refer above code)
U may not included cors as it allows u to have more resourses , without cors heroku prevent some dependencies to not install in heroku (refer above code)
Try replacing "io" to "io.connect"
const socket = io.connect('https://localhost:8080/')
Must write tag at the end in the HTML
U may forget to add this code which is must in "socket.io"
It is required in your html file
delete "node_modules" and "package-lock.json"
and write "npm i" in cmd
This should be in package.json 's scripts
"start":"node index.js",
I am not talking about nodemon , use simple node over here
May be version is creating a problem , u can avoid it by copying all "devDependencies" to "dependencies" in "package.json" and put "*" in version like this
"dependencies": {
"cors": "*",
"express": "*",
"nodemon": "*",
"socket.io": "*"
},
"devDependencies": {}

Answer 4

Are you sure you have socket io installed? Try running:
npm install socket.io
This will install the latest socket.io available in nodes packet repository.