issues while installing engine.io node js

Question

I am trying to install engine.io (https://www.npmjs.com/package/engine.io)

I am getting the following error:

C:\Windows\system32>npm install engine.io

[email protected] install C:\Windows\system32\node_modules\engine.io\node_modules\ws
(node-gyp rebuild 2> builderror.log) || (exit 0)


C:\Windows\system32\node_modules\engine.io\node_modules\ws>node "C:\Program File
s (x86)\nodejs\node_modules\npm\bin\node-gyp-bin\\..\..\node_modules\node-gyp\bi
n\node-gyp.js" rebuild
[email protected] node_modules\engine.io
├── [email protected]
├── [email protected] ([email protected])
├── [email protected] ([email protected], [email protected], [email protected], ba
[email protected], [email protected], [email protected])
└── [email protected] ([email protected], [email protected], [email protected])

After this I try to execute this js script

var engine = require('engine.io');
var server = engine.listen(80);

server.on('connection', function(socket){
  socket.send('utf 8 string');
  socket.send(new Buffer([0, 1, 2, 3, 4, 5])); // binary data
});

I get this error

C:\Windows\system32>node "c:\users\user\documents\visual studio 2010\Projec ts\nodes\WebApplication1\NodeFiles\engineTest.js"
module.js:338
throw err;
^
Error: Cannot find module 'engine.io'
at Function.Module._resolveFilename (module.js:336:15)
at Function.Module._load (module.js:278:25)
at Module.require (module.js:365:17)
at require (module.js:384:17)
at Object. (c:\users\user\documents\visual studio 2010\Proje cts\node\WebApplication1\NodeFiles\engineTest.js:1:76)
at Module._compile (module.js:460:26)
at Object.Module._extensions..js (module.js:478:10)
at Module.load (module.js:355:32)
at Function.Module._load (module.js:310:12)
at Function.Module.runMain (module.js:501:10)

--------------------------------------------------------------------------

Actually I think I am not doing something right. Let me explain

First of all i think the installation of engine.io is correct as all of you are suggesting.

Now when I try running the command "var engine = require('engine.io');" from the node console, it works perfectly and the engine variable is instantiated with the data.

When I check engine it shows me.

C:\Users\Ankur>node
> var engine = require('engine.io');
undefined
> engine
{ [Function]
  protocol: 1,
  Server:
   { [Function: Server]
     errors:
      { UNKNOWN_TRANSPORT: 0,
        UNKNOWN_SID: 1,
        BAD_HANDSHAKE_METHOD: 2,
        BAD_REQUEST: 3 },
     errorMessages:
      { '0': 'Transport unknown',
        '1': 'Session ID unknown',
        '2': 'Bad handshake method',
        '3': 'Bad request' } },
  Socket: [Function: Socket],
  Transport: [Function: Transport],
  transports:
   { polling: { [Function: polling] upgradesTo: [Object] },
     websocket: [Function: WebSocket] },
  parser:
   { protocol: 3,
     packets:
      { open: 0,
        close: 1,
        ping: 2,
        pong: 3,
        message: 4,
        upgrade: 5,
        noop: 6 },
     encodePacket: [Function],
     encodeBase64Packet: [Function],
     decodePacket: [Function],
     decodeBase64Packet: [Function],
     encodePayload: [Function],
     decodePayload: [Function],
     encodePayloadAsBinary: [Function],
     decodePayloadAsBinary: [Function] },
  listen: [Function: listen],
  attach: [Function: attach] }
>

But when I write that line in a JS file and then try and run it with the node command it breaks.Error

C:\Users\Ankur>node "e:\engine.js"
module.js:338
    throw err;
          ^
Error: Cannot find module 'engine.io'
    at Function.Module._resolveFilename (module.js:336:15)
    at Function.Module._load (module.js:278:25)
    at Module.require (module.js:365:17)
    at require (module.js:384:17)
    at Object.<anonymous> (e:\engine.js:1:76)
    at Module._compile (module.js:460:26)
    at Object.Module._extensions..js (module.js:478:10)
    at Module.load (module.js:355:32)
    at Function.Module._load (module.js:310:12)
    at Function.Module.runMain (module.js:501:10)

C:\Users\Ankur>

I think I am doing something silly.

Could someone please help me out?

Answer 1

You have installed the engine.io module under the directory C:\Windows\system32. This means that you have a node_modules folder in systems32, not in your project folder. This is not what you want.

I would recommend you start from scratch:

Open the cmd and do the following commands

1. Create a folder for your project:
   • mkdir testproject
2. Navigate into the text projects folder:
   • cd testproject
3. Install the modules you require, i.e. engine.io:
   • npm install engine.io
4. Now you should have a folder named node_modules in your project folder
5. Create the file app.js in the project folder with your content.
6. Run app.js
   • node app.js

Your app should now work.