npm中package.json

通常我们使用npm init命令来创建一个npm程序时，会自动生成一个package.json文件。package.json文件会描述这个NPM包的所有相关信息，包括作者、简介、包依赖、构建等信息，格式是严格的JSON格式。

常用命令

npm i --save packageName 安装依赖包
npm i --save-dev packageName
npm i [email protected] 安装指定版本的包，版本号用@符号连接

属性介绍

• name
  name和version是package.json中最重要的两个字段，也是发布到NPM平台上的唯一标识，如果没有正确设置这两个字段，包就不能发布和被下载。
• version
  包的版本号。如"1.0.0"。
• license
  包的开源协议名称。
• main
  包的入口文件。
• repository
  包的仓库地址。

"repository": {
    "type": "git",
    "url": "git+https://github.com/rainnaZR/es6-react.git"
  },

• scripts
  通过设置这个可以使NPM调用一些命令脚本，封装一些功能。

"scripts": {"start": "babel-node src/pages/index.js",
    "build": "webpack --config config/webpack.config.js",
    "watch": "webpack-dev-server --config config/webpack.config.js --hot --inline --progress"
  }

比较有用

  "scripts": {
    "clean": "rimraf dist",
    "compile": "better-npm-run compile",
    "lint": "eslint src tests server",
    "lint:fix": "npm run lint -- --fix",
    "start": "better-npm-run start",
    "dev": "better-npm-run dev",
    "portal": "better-npm-run portal",
    "test": "jest --config jest.config.js",
    "test:dev": "npm run test -- --watch",
    "deploy": "better-npm-run deploy",
    "deploy:dev": "better-npm-run deploy:dev",
    "deploy:prod": "better-npm-run deploy:prod",
    "codecov": "cat coverage/*/lcov.info | codecov",
    "i18n": "better-npm-run i18n"
  },

• dependencies
  指定依赖的其它包，这些依赖是指包发布后正常执行时所需要的，也就是线上需要的包。使用下面的命令来安装：

npm install --save packageName

如果是开发中依赖的包，可以在devDependencies设置。

• devDependencies
  这些依赖只有在开发时候才需要。使用下面的命令来安装：

npm install --save-dev packageName 

demo:

{
  "name": "react",
  "version": "1.0.0",
  "description": "Command line instructions",
  "keywords": [
    "react",
    "es6",
    "react with es6"
  ],
  "homepage": "https://github.com/rainnaZR/es6-react",
  "bugs": {
    "url": "https://github.com/rainnaZR/es6-react",
    "email": "[email protected]"
  },
  "license": "ISC",
  "author": "ZRainna",
  "main": "src/pages/index.js",
  "directories": {
    "tests": "tests",
    "lib":"lib",
    "docs":"docs"
  },
  "repository": {
    "type": "git",
    "url": "git+https://github.com/rainnaZR/es6-react.git"
  },
  "scripts": {"start": "babel-node src/pages/index.js",
    "build": "webpack --config config/webpack.config.js",
    "watch": "webpack-dev-server --config config/webpack.config.js --hot --inline --progress"
  },
  "babel": {
    "presets": [
      "es2015-node5"
    ]
  },
  "devDependencies": {
    "webpack": "^1.13.2",
    "webpack-dev-server": "^1.16.1"
  },
  "dependencies": {
    "babel-loader": "^6.2.5",
    "babel-preset-es2015": "^6.14.0",
    "babel-preset-react": "^6.11.1",
    "react": "^15.3.2",
    "react-dom": "^15.3.2",
    "react-redux": "^4.4.5",
    "react-router": "^2.8.1",
    "redux": "^3.6.0"
  }
}