NPM global install “cannot find module”

Question

I wrote a module which I published to npm a moment ago (https://npmjs.org/package/wisp)

So it installs fine from the command line:

$ npm i -g wisp

However, when I run it from the command line, I keep getting an error that optimist isn't installed:

$ wisp 
Error: Cannot find module 'optimist'
    at Function.Module._resolveFilename (module.js:338:15)
    at Function.Module._load (module.js:280:25)
    at Module.require (module.js:362:17)
    at require (module.js:378:17)
    at Object.<anonymous> (/usr/local/lib/node_modules/wisp/wisp:12:10)
    at Object.<anonymous> (/usr/local/lib/node_modules/wisp/wisp:96:4)
    at Module._compile (module.js:449:26)
    at Object.exports.run (/usr/local/lib/node_modules/coffee-script/lib/coffee-script/coffee-script.js:68:25)
    at compileScript (/usr/local/lib/node_modules/coffee-script/lib/coffee-script/command.js:135:29)
    at fs.stat.notSources.(anonymous function) (/usr/local/lib/node_modules/coffee-script/lib/coffee-script/command.js:110:18)

However, I have specified in package.json as a dependancy:

{
  "name": "wisp",
  "author": "Brendan Scarvell <[e-mail]>",
  "version": "0.1.0",
  "description": "Global nodejs file server",
  "dependencies": {
    "optimist": "~0.3.4"
  },
  "repository": "git://github.com/tehlulz/wisp",
  "bin": {
    "wisp" : "./wisp"
  }
}

Does anyone know what to do to get this running? I know its to do with the bin part adding the executable to bin and the node_modules in that directory being empty. No idea how to resolve this.

Answer 1

I got this error Error: Cannot find module 'number-is-nan' whereas the module actually exists. It was due to a bad/incomplete Node.js installation.

For Windows , as other answers suggest it, you need a clean Node installation :

• Uninstall Node.js
• Delete the two folders npm and npm_cache in C:\Users\user\AppData\Roaming
• Restart Windows and install Node.js
• Run npm initor (npm init --yes for default config)
• Set the Windows environment variable for NODE_PATH. This path is where your packages are installed. It's probably something likeNODE_PATH = C:\Users\user\node_modules or C:\Users\user\AppData\Roaming\npm\node_modules
• Start a new cmd console and npm should work fine

Note :

Try the last points before reinstalling Node.js, it could save you some time and avoid to re-install all your packages.

Answer 2

For Windows, from Nodejs cannot find installed module on Windows? what worked for me is running npm link as in

npm link wisp

Answer 3

I did this in simple way...

1. Un-Install node from control panel [Windows 7]
2. Install node again
3. Install protractor npm install --global --verbose protractor
   Update web driver manager.
   

works fine for me.

Hope this helps you....

Answer 4

I had this problem for request-promise. In my case, replacing:

npm install request-promise --global

with

npm install request-promise --cli

worked (source)

Also, try setting the environment variable

NODE_PATH=%AppData%\npm\node_modules