node.js - 无法访问全局安装的节点模块

Question

我尝试使用命令 安装@hapi/joi

alok@alok-HP-Laptop-14s-cr1xxx:~/tmp/js$ sudo npm install @hapi/joi -g
+ @hapi/joi@16.1.7
updated 1 package in 2.833s

我可以看到安装@hapi/joi在/usr/local/lib/node_modules

alok@alok-HP-Laptop-14s-cr1xxx:~/tmp/js/tmp$ npm root -g
/usr/local/lib/node_modules

alok@alok-HP-Laptop-14s-cr1xxx:~/tmp/js/tmp$ npm list -g @hapi/joi
/usr/local/lib
`-- @hapi/joi@16.1.7  

alok@alok-HP-Laptop-14s-cr1xxx:~/tmp/js$ tree /usr/local/lib/node_modules/@hapi/joi/ -L 1
/usr/local/lib/node_modules/@hapi/joi/
├── CHANGELOG.md
├── dist
├── lib
├── LICENSE.md
├── node_modules
├── package.json
└── README.md

3 directories, 4 files

但我无法访问它

alok@alok-HP-Laptop-14s-cr1xxx:~/tmp/js$ node
> var Joi = require('@hapi/joi'); // this is not working
{ Error: Cannot find module '@hapi/joi'
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:581:15)
    at Function.Module._load (internal/modules/cjs/loader.js:507:25)
    at Module.require (internal/modules/cjs/loader.js:637:17)
    at require (internal/modules/cjs/helpers.js:22:18) code: 'MODULE_NOT_FOUND' }
> 
> 
> var Joi = require('/usr/local/lib/node_modules/@hapi/joi') // This is working
undefined

我的node和npm是

alok@alok-HP-Laptop-14s-cr1xxx:~/tmp/js$ which node
/usr/bin/node
alok@alok-HP-Laptop-14s-cr1xxx:~/tmp/js$ node -v
v10.15.2
alok@alok-HP-Laptop-14s-cr1xxx:~/tmp/js$ npm -v
6.11.3

alok@alok-HP-Laptop-14s-cr1xxx:~/tmp/js$ echo $NODE_PATH # this shows nothing

alok@alok-HP-Laptop-14s-cr1xxx:~/tmp/js$ node
> process['env']['PATH']
'/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin'
>

为什么我得到Error: Cannot find module '@hapi/joi'？如何解决这个问题？

Answer 1

添加/usr/local/lib/node_modules使其NODE_PATH工作

# Add this line in yuor ~/.bashrc
export NODE_PATH="/usr/local/lib/node_modules:$NODE_PATH"

或者

# Add this line in yuor ~/.bashrc
export NODE_PATH="`npm root -g`:$NODE_PATH"

或者

// Add this line at top in your node.js script
module.paths.push('/usr/local/lib/node_modules/')

在Ubuntu 20.04上测试，这应该也适用于其他Linux 发行版。

Answer 2

你应该使用 npm init 它会生成 package.json 然后你可以运行你的 js 文件。

Answer 3

你检查过你的用户文件夹吗？我node_module这里有一个文件夹/Users/<username>/node_modules它可能在里面。

你将不得不改变$PATH也许。