如何发布一个NPM包

1，编写模块
作为演示实例，新建一个sayHi.js文件，相关代码如下：

exports.sayHi = function(){
    return 'Hello World';
}

2，初始化包
package.json文件的内容尽管相对较多，，但实际发布一个包时并不需要一行一行的编写。使用 npm init 命令（在终端执行）就能帮你生成package.json文件。(NPM会通过提问式的交互逐个填入选项就行)

> npm init
//然后根据提示操作就行了
//执行结果
npm WARN config production Use `--omit=dev` instead.
npm WARN config production Use `--omit=dev` instead.
This utility will walk you through creating a package.json file.
It only covers the most common items, and tries to guess sensible defaults.

See `npm help init` for definitive documentation on these fields
and exactly what they do.

Use `npm install <pkg>` afterwards to install a package and
save it as a dependency in the package.json file.

Press ^C at any time to quit.
package name: (a01) a01
version: (1.0.0) 0.0.1
description: A hello world package
git repository:
keywords:  Hello World
author: smzk
license: (ISC)
About to write to E:\webqBasic\package.json:

{
  "name": "a01",
  "version": "0.0.1",
  "description": "A hello world package",
  "main": "know.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "smzk",
  "license": "ISC",
  "dependencies": {
    "express": "^4.18.2"
  },
  "devDependencies": {},
  "keywords": [
    "Hello",
    "World"
  ]
}

Is this OK? (yes)

3，注册包仓库账号
为了维护包，NPM必须要使用仓库账号才允许将包发布到仓库中。注册账号的命令是 npm adduser 。（也是提问式的交互）

> npm adduser
//然后根据提示操作就行了
//执行结果
npm WARN config production Use `--omit=dev` instead.
npm WARN config production Use `--omit=dev` instead.
npm WARN adduser `adduser` will be split into `login` and `register` in a future version. `adduser` will become an alias of `register`. `login` (currently an alias) will 
become its own command.
npm notice Log in on https://registry.npmjs.org/
Username: smzk
Password:
Email: (this IS public) 2717141437@qq.com
npm notice Please check your email for a one-time password (OTP)
Enter one-time password: 60185323
Logged in as smzk on https://registry.npmjs.org/.

注意：可能注册的时候会报下面的错误（[FORBIDDEN] Public registration is not allowed）

npm WARN config production Use `--omit=dev` instead.
npm WARN adduser `adduser` will be split into `login` and `register` in a future version. `adduser` will become an alias of `register`. `login` (currently an alias) will 
become its own command.
npm notice Log in on https://registry.npmmirror.com/
Username: smzk
Password:
Email: (this IS public) 2717141437@qq.com
npm ERR! code E403
npm ERR! 403 403 Forbidden - PUT https://registry.npmmirror.com/-/user/org.couchdb.user:smzk - [FORBIDDEN] Public registration is not allowed
npm ERR! 403 In most cases, you or one of your dependencies are requesting
npm ERR! 403 a package version that is forbidden by your security policy, or
npm ERR! 403 on a server you do not have access to.

npm ERR! A complete log of this run can be found in:

问题原因：是你的NPM使用了镜像地址。
解决方法：输入命令 npm config set registry https://registry.npmjs.org/ 即可

查看npm源：
> npm config get registry
切换npm源方法一：
> npm config set registry http://registry.npmjs.org
切换npm源方法二：
> nrm use npm

4，上传包
上传包的命令 npm publish ，

>  npm publish .
//执行结果
npm WARN config production Use `--omit=dev` instead.
npm notice
npm notice 📦  a01@0.0.1
npm notice === Tarball Contents ===
npm notice 254B know.js
npm notice 345B package.json
npm notice === Tarball Details ===
npm notice name:          a01
npm notice version:       0.0.1
npm notice filename:      a01-0.0.1.tgz
npm notice package size:  464 B
npm notice unpacked size: 599 B
npm notice shasum:        22f555f7736aaa790dc9292d0f8e4a07d5219100
npm notice integrity:     sha512-DLR4vVCfYQcPp[...]9RyTObjzLfOow==
npm notice total files:   2
npm notice
npm notice Publishing to https://registry.npmjs.org/
+ a01@0.0.1

5，安装包
为了测试自己上传的包，可以换一个目录执行命令 npm install a01 （a01 是包名）

> npm install a01 
//执行结果
npm WARN config production Use `--omit=dev` instead.
npm WARN config production Use `--omit=dev` instead.
added 58 packages, and audited 59 packages in 13s

7 packages are looking for funding
  run `npm fund` for details

6，管理包权限
如果需要多人对包进行发布，可以使用命令 npm owner 帮助你

//查看管理包的所有者
> npm owner ls a01
//执行结果
npm WARN config production Use `--omit=dev` instead.
npm WARN config production Use `--omit=dev` instead.
smzk <2717141437@qq.com>

//添加包的拥有者
> npm owner add <user> <package name>

//删除包的拥有者
> npm owner rm <user> <package name>

7，拓展（分析包）
在使用NPM过程种，当你不能确定当前目录下能否可以通过require()顺利引入想要的包时，可以执行命令 npm ls 分析包。
这个命令可以分析出当前路径下能够通过模块路径找到的所有包，并生成依赖树。

├── connect-mongo@4.6.0
├── cookie-parser@1.4.6
├── debug@2.6.9
├── ejs@2.6.2
├── express-session@1.17.3
├── express@4.16.4
├── http-errors@1.6.3
├── jsonwebtoken@8.5.1
├── mongoose@6.6.6
├── morgan@1.9.1
└── multer@1.4.5-lts.1