Nodejs cannot find installed module on Windows?

问题:

I am learning nodejs at the moment on Windows. Several modules are installed globally with npm.cmd, and nodejs failed to find the installed modules. Take jade for example,

npm install jade -g

Jade is installed in directory \"C:\\Program Files (x86)\\nodejs\\node_modules\", but the following code will fail with a \"Cannot find module \'jade\'\" error,

var jade = require(\'jade\');

However, the code will run successfully when jade is locally installed (without -g option in npm). I don\'t want to use locally-installed modules, it\'s a waste of disk space for me, can someone help me to make the globally-installed modules work on Windows?

回答1:

Add an environment variable called NODE_PATH and set it to %USERPROFILE%\\Application Data\\npm\\node_modules (Windows XP), %AppData%\\npm\\node_modules (Windows 7/8/10), or wherever npm ends up installing the modules on your Windows flavor. To be done with it once and for all, add this as a System variable in the Advanced tab of the System Properties dialog (run control.exe sysdm.cpl,System,3).

Quick solution in Windows 7+ is to just run:

rem for future
setx NODE_PATH %AppData%\\npm\\node_modules
rem for current session
set NODE_PATH=%AppData%\\npm\\node_modules

It\'s worth to mention that NODE_PATH is only used when importing modules in Node apps. When you want to use globally installed modules\' binaries in your CLI you need to add it also to your PATH, but without node_modules part (for example %AppData%\\npm in Windows 7/8/10).

---

Old story

I\'m pretty much new to node.js myself so I can be not entirely right but from my experience it\'s works this way:

1. -g is not a way to install global libraries, it\'s only a way to place them on system path so you can call them from command line without writing the full path to them. It is useful, for example, then node app is converting local files, like less — if you install it globally you can use it in any directory.
2. node.js itself didn\'t look at the npm global dir, it is using another algorithm to find required files: http://nodejs.org/api/modules.html#modules_file_modules (basically its scanning every folder in the path, starting from the current for node_modules folder and checks it).

See similar question for more details: How do I install a module globally using npm?

回答2:

if you are in the windows7 platform maybe you should change the NODE_PATH like this: %AppData%\\npm\\node_modules

回答3:

I know i can awake a zombie but i think this is still a problem, if you need global access to node modules on Windows 7 you need to add this to your global variable path:

C:\\Users\\{USER}\\AppData\\Roaming\\npm

Important: only this without the node_modules part, took me half hour to see this.

回答4:

For making it work on windows 10 I solved it by adding the folder %USERPROFILE%\\AppData\\Roaming\\npm to my PATH. Having \\node_modules appended like this: %USERPROFILE%\\AppData\\Roaming\\npm\\node_modules\\ did not work for me.

回答5:

I\'ll just quote from this node\'s blog post...

In general, the rule of thumb is:

• If you’re installing something that you want to use in your program, using require(\'whatever\'), then install it locally, at the root of your project.
• If you’re installing something that you want to use in your shell, on the command line or something, install it globally, so that its binaries end up in your PATH environment variable.

...

Of course, there are some cases where you want to do both. Coffee-script and Express both are good examples of apps that have a command line interface, as well as a library. In those cases, you can do one of the following:

1. Install it in both places. Seriously, are you that short on disk space? It’s fine, really. They’re tiny JavaScript programs.
2. Install it globally, and then npm link coffee-script or npm link express (if you’re on a platform that supports symbolic links.) Then you only need to update the global copy to update all the symlinks as well.

回答6:

To make it short, use npm link jade in your app directory.

回答7:

Tried to add/edit environment variables and come to conclude that:

1. Edit/add User variables (of the upper box) instead of System variables (of the lower part); otherwise you have to \"run as administrator\" to get it work.
2. Append ;%AppData%\\npm to Path in order to use it as a command line tool (if supported, like jshint and grunt-cli).
3. Create NODE_PATH and set it %AppData%\\npm\\node_modules in order to require(\'<pkg_name>\') in scripts without install it in the project directory. (But npm link is suggested for this requirement if you\'re working on OS with mklink such as Vista and newer.)

Test environment:

• Win 7 (Ent., 64-bit, SP1), Node.js 4.2.4, npm 2.14.12
• Win 8.1 (Ent., 64-bit), Node.js 0.10.30, npm 1.4.21

回答8:

I ran into this issue on Windows 7, running

npm install -g gulp

as administrator while being logged on as a normal user.

Solution: When executing the same installation as normal user (not \"run as admin\" for cmd) all was fine. I guess it is related to the default install and search path.

回答9:

I had a terrible time getting global modules to work. Eventually, I explicitly added C:\\Users\\yourusername\\AppData\\Roaming\\npm to the PATH variable under System Variables. I also needed to have this variable come before the nodejs path variable in the list.

I am running Windows 10.

回答10:

From my expierience with win8.1 npm installs modules on C:\\Users\\[UserName]\\AppData\\Roaming\\npm\\node_modules but dumply searches them on C:\\Users\\[UserName]\\node_modules.

One simple solution reference module in application by full path:

var jsonminify = require(\"C:/Users/Saulius/AppData/Roaming/npm/node_modules/jsonminify\");

回答11:

For windows, everybody said you should set environment variables for nodejs and npm modules, but do you know why? For some modules, they have command line tool, after installed the module, there\'are [module].cmd file in C:\\Program Files\\nodejs, and it\'s used for launch in window command. So if you don\'t add the path containing the cmd file to environment variables %PATH% , you won\'t launch them successfully through command window.

回答12:

Alternatively you could add to ~/.npmrc right prefix. I\'ve got C:\\Program Files\\nodejs for 64 Win7.

回答13:

I stumbled on this question because I want to use node.js with visual studio 2015 on my new computer with windows 10. I used node.js on windows 7 and 8 and 8.1 Never a problem node.js finding a module. I use a legacy node.js 0.10.39 because I have to use this version because of the serial and RFXCOM module.

The answer for windows 10 is to set the NODE_PATH in the enviroment variables with C:\\Users\\User\\node_modules.

回答14:

For Windows 10, I had to locally install gulp in the folder:

C:\\Users\\myaccount\\AppData\\Roaming\\npm\\node_modules

npm install gulp

This fixed my issue of \"gulp is not recognized\"

回答15:

I had the same issue, trying to install bower with npm install -g bower

I think this was because node was installed by another user, not me.

I uninstalled node, and then I reinstalled it. During installation, I saw this text for the option Add to PATH > npm modules:

Message in node installation

After node installation, I executed npm install -g bower again. And now bower works.

Sure is not necessary reinstall node with own user, like me. Solution must be via NODE_PATH or PATH variables, as other users have explained.

This is only to remark that this problem occurs only if node has been installed by another user (or if during installation the option Add to PATH > npm modules has not been marked).

回答16:

Just download and re-install the node from this and this will fix all the path issues.

Don\'t forget to restart your command prompt or terminal.

回答17:

if you are using windows , it takes some steps , 1) create a file called package.json

 {
  \"name\": \"hello\"
, \"version\": \"0.0.1\"
, \"dependencies\": {
    \"express\": \"*\"
  }
}

where hello is the name of the package and * means the latest version of your dependency

2) code to you project directory and run the following command

npm install

It installs the dependencies