npm knowledge basics

npm inro

https://www.npmjs.com/

npm is the package manager for javascript

npm 为 nodejs默认的包管理工具， 为nodejs软件内置。

安装nodejs后， 使用 npm install xxx 可以安装第三方软件库

对于开发者自己建立一个npm工程， 使用npm init完成。

demo

各个参数解读，见官方文档：

https://docs.npmjs.com/files/package.json#version

{

"name": "dijistra",

"version": "1.0.4",

"description": "a simple dijistra implementation of js version",

"main": "./dist/dijistra.umd.js",

"scripts": {

"build": "webpack --config webpack-config.js",

"publish": "npm publish",

"lint": "eslint src"

},

"keywords": ["dijistra", "algorithm"],

"author": "lightsong",

"license": "MIT",

"repository": {

"type": "git",

"url": "https://github.com/fanqingsong/dijistra_algorithm"

},

"devDependencies": {

"babel-core": "^6.9.1",

"babel-eslint": "^6.0.4",

"babel-loader": "^6.2.4",

"babel-plugin-syntax-dynamic-import": "^6.18.0",

"babel-preset-es2015": "^6.9.0",

"babel-preset-stage-2": "^6.5.0",

"css-loader": "^0.23.1",

"eslint": "^2.12.0",

"eslint-config-airbnb-base": "^3.0.1",

"eslint-plugin-babel": "^3.2.0",

"html-webpack-plugin": "^2.21.0",

"style-loader": "^0.13.1",

"webpack": "^3.5.4",

"webpack-dev-server": "^1.14.1"

},

"dependencies": {

"pleasejs": "^0.4.2"

}

}

版本号含义

版本号的格式有多种， 支持各种需求场景。 

默认 npm install --save-dev xxx 是按照兼容格式来  ^ x.xx.xx

https://docs.npmjs.com/files/package.json#dependency

See semver for more details about specifying version ranges.

• version Must match version exactly
• >version Must be greater than version
• >=version etc
• <version
• <=version
• ~version “Approximately equivalent to version” See semver
• ^version “Compatible with version” See semver
• 1.2.x 1.2.0, 1.2.1, etc., but not 1.3.0
• http://... See ‘URLs as Dependencies’ below
• * Matches any version
• "" (just an empty string) Same as *
• version1 - version2 Same as >=version1 <=version2.
• range1 || range2 Passes if either range1 or range2 are satisfied.
• git... See ‘Git URLs as Dependencies’ below
• user/repo See ‘GitHub URLs’ below
• tag A specific version tagged and published as tag See npm-dist-tag
• path/path/path See Local Paths below

详细说明：

https://docs.npmjs.com/misc/semver

Hyphen Ranges X.Y.Z - A.B.C§

Specifies an inclusive set.

• 1.2.3 - 2.3.4 := >=1.2.3 <=2.3.4

X-Ranges 1.2.x 1.X 1.2.* *§

Any of X, x, or * may be used to “stand in” for one of the numeric values in the [major, minor, patch] tuple.

• * := >=0.0.0 (Any version satisfies)
• 1.x := >=1.0.0 <2.0.0 (Matching major version)
• 1.2.x := >=1.2.0 <1.3.0 (Matching major and minor versions)

Tilde Ranges ~1.2.3 ~1.2 ~1§

Allows patch-level changes if a minor version is specified on the comparator. Allows minor-level changes if not.

• ~1.2.3 := >=1.2.3 <1.(2+1).0 := >=1.2.3 <1.3.0
• ~1.2 := >=1.2.0 <1.(2+1).0 := >=1.2.0 <1.3.0 (Same as 1.2.x)
• ~1 := >=1.0.0 <(1+1).0.0 := >=1.0.0 <2.0.0 (Same as 1.x)
• ~0.2.3 := >=0.2.3 <0.(2+1).0 := >=0.2.3 <0.3.0
• ~0.2 := >=0.2.0 <0.(2+1).0 := >=0.2.0 <0.3.0 (Same as 0.2.x)
• ~0 := >=0.0.0 <(0+1).0.0 := >=0.0.0 <1.0.0 (Same as 0.x)
• ~1.2.3-beta.2 := >=1.2.3-beta.2 <1.3.0 Note that prereleases in the 1.2.3 version will be allowed, if they are greater than or equal to beta.2. So, 1.2.3-beta.4 would be allowed, but 1.2.4-beta.2 would not, because it is a prerelease of a different [major, minor, patch] tuple.

Caret Ranges ^1.2.3 ^0.2.5 ^0.0.4§

Allows changes that do not modify the left-most non-zero digit in the [major, minor, patch] tuple. In other words, this allows patch and minor updates for versions 1.0.0 and above, patch updates for versions 0.X >=0.1.0, and no updates for versions 0.0.X.

Many authors treat a 0.x version as if the x were the major “breaking-change” indicator.

Caret ranges are ideal when an author may make breaking changes between 0.2.4 and 0.3.0 releases, which is a common practice. However, it presumes that there will not be breaking changes between 0.2.4 and 0.2.5. It allows for changes that are presumed to be additive (but non-breaking), according to commonly observed practices.

• ^1.2.3 := >=1.2.3 <2.0.0
• ^0.2.3 := >=0.2.3 <0.3.0
• ^0.0.3 := >=0.0.3 <0.0.4
• ^1.2.3-beta.2 := >=1.2.3-beta.2 <2.0.0 Note that prereleases in the 1.2.3 version will be allowed, if they are greater than or equal to beta.2. So, 1.2.3-beta.4 would be allowed, but 1.2.4-beta.2 would not, because it is a prerelease of a different [major, minor, patch] tuple.
• ^0.0.3-beta := >=0.0.3-beta <0.0.4 Note that prereleases in the 0.0.3 version only will be allowed, if they are greater than or equal to beta. So, 0.0.3-pr.2 would be allowed.

npm发布

https://www.jianshu.com/p/d9fb02a891d9

先到官网上注册， 然后使用邮箱确认。

本地登录，输入完用户名，密码，邮箱后没有错误信息就完成了。

$ npm adduser
Username: your name
Password: your password
Email: (this IS public) your email

要设置一个版本号

npm社区版本号规则采用的是semver（语义化版本），主要规则版本格式：主版本号.次版本号.修订号，版本号递增规则如下：

• 主版本号：当你做了不兼容的 API 修改，
• 次版本号：当你做了向下兼容的功能性新增，
• 修订号：当你做了向下兼容的问题修正。
  先行版本号及版本编译信息可以加到“主版本号.次版本号.修订号”的后面，作为延伸。

　　发布

 npm publish

// 需要设置库URL

npm config set registry=http://registry.npmjs.org

例子：

https://www.npmjs.com/package/dijistra