npm link not working on windows?

Question

I'm using node v0.10.32. Windows 8.1.

My objective is to link a node application as a node_module in another main app.

I go to my-module folder and do

npm link

Then, I go to the main-app folder and do

npm link my-module

This is the result

c:\dev\main-app>npm link my-module
unbuild [email protected]
c:\dev\main-app\node_modules\my-module ->     C:\Users\Nizar\AppData\Roaming\npm\node_modules\my-module -> C:\dev\my-module

But, the linkage does NOT seem to work, require('my-module') throws the following error

    c:\dev\main-app>node app.js

    module.js:340
        throw err;
              ^
    Error: Cannot find module 'my-module'
        at Function.Module._resolveFilename (module.js:338:15)

• my-module is indeed v0.0.2.
• I can access it from main-app/node_module/my-module
• This folder exists C:\Users\Nizar\AppData\Roaming\npm\node_modules\my-module
• my-module package.json has "name": "my-module"

Moreover, %NODE_PATH% is correctly set:

  c:\dev\main-app>echo %NODE_PATH%
  C:\Users\Nizar\AppData\Roaming\npm\node_modules

Ideas?

Answer 1

There are a few things to try. On Windows, npm link is handled by creating junction points. Issuing a dir node_modules command should result in a line like:

01/15/2016 11:02 AM <JUNCTION> my-module [C:\Users\Nizar\AppData\Roaming\npm\node_modules\my-module]

Assuming that's there, then the problem is more than likely:

1. A lack of an index.js file (which is the default filename node uses to resolve modules)
2. You're using a different file than index.js as the main file of your module, in which case you need to tell node what that file is, by using the main key in your package.json file.

For example (taken from here):

{
  "name": "node-js-sample",
  "version": "0.2.0",
  "description": "A sample Node.js app using Express 4",
  "main": "index.js", // <-- LIKE THIS
  "scripts": {
    "start": "node index.js"
  },
  "dependencies": {
    "express": "^4.13.3"
  },
  "engines": {
    "node": "4.0.0"
  },
  "repository": {
    "type": "git",
    "url": "https://github.com/heroku/node-js-sample"
  },
  "keywords": [
    "node",
    "heroku",
    "express"
  ],
  "author": "Mark Pundsack",
  "contributors": [
    "Zeke Sikelianos <[email protected]> (http://zeke.sikelianos.com)"
  ],
  "license": "MIT"
}