Brendan Scarvell Brendan Scarvell - 4 months ago 22
Node.js Question

NPM global install "cannot find module"

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 <bscarvell@gmail.com>",
"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

For anyone else running into this, I had this problem due to my npm installing into a location that's not on my NODE_PATH.

[root@uberneek ~]# which npm
/opt/bin/npm
[root@uberneek ~]# which node
/opt/bin/node
[root@uberneek ~]# echo $NODE_PATH

My NODE_PATH was empty, and running npm install --global --verbose promised-io showed that it was installing into /opt/lib/node_modules/promised-io:

[root@uberneek ~]# npm install --global --verbose promised-io
npm info it worked if it ends with ok
npm verb cli [ '/opt/bin/node',
npm verb cli   '/opt/bin/npm',
npm verb cli   'install',
npm verb cli   '--global',
npm verb cli   '--verbose',
npm verb cli   'promised-io' ]
npm info using npm@1.1.45
npm info using node@v0.8.4
[cut]
npm info build /opt/lib/node_modules/promised-io
npm verb from cache /opt/lib/node_modules/promised-io/package.json
npm verb linkStuff [ true, '/opt/lib/node_modules', true, '/opt/lib/node_modules' ]
[cut]

My script fails on require('promised-io/promise'):

[neek@uberneek project]$ node buildscripts/stringsmerge.js 

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

I probably installed node and npm from source using configure --prefix=/opt. I've no idea why this has made them incapable of finding installed modules. The fix for now is to point NODE_PATH at the right directory:

export NODE_PATH=/opt/lib/node_modules

My require('promised-io/promise') now succeeds.