常用包

• 框架：
  yarn add express
• 数据库链接：
  yarn add sequelize
  yarn add mysql2
• 处理 favicon：
  yarn add serve-favicon
• 纪录日志：
  yarn add morgan
• 生成文档：
  yarn add --dev apidoc
• 解析请求参数：
  yarn add body-parser
• 设置 HTTP 头(提高安全性)：
  yarn add helmet
• 文件变动监控(自动重启)：
  yarn add --dev nodemon (启动服务器脚本中替换 node 即可)
• 允许 cors 请求：
  yarn add cors
• 压缩数据：
  yarn add compression
• 响应时间:
  yarn add response-time
• 数据伪造:
  yarn add faker
  – 数据验证:
  yarn add express-validator
• 进程管理:
  yarn add --dev pm2
  带重启(nodemon用于开发环境)，日志，负载均衡

serve-favicon

优点：把请求 favicon 的记录从日志中去除。缓存 icon 提高性能。使用兼容性最好的 Content-Type。
使用方式：

var favicon = require('serve-favicon')

app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')))

morgan

使用方式：

var morgan = require('morgan')

app.use(morgan('combined')) //参数可选 dev tiny 或自定义输出日志格式，详见文档

// 导出日志文件
var express = require('express')
var fs = require('fs')
var morgan = require('morgan')
var path = require('path')

var app = express()

// create a write stream (in append mode)
var accessLogStream = fs.createWriteStream(path.join(__dirname, 'access.log'), {flags: 'a'})

// setup the logger
app.use(morgan('combined', {stream: accessLogStream}))

body-parser

使用方式：

var bodyParser = require('body-parser')

// parse application/x-www-form-urlencoded
app.use(bodyParser.urlencoded({ extended: false }))
//设置 false 使用 querystring 解析，处理 ajax 提交的复杂数据更在行。(true 使用 qs 解析)
// parse application/json
app.use(bodyParser.json())

apidoc

使用方式:
生成文档命令: apidoc -i routes/ -o doc/( routes 是程序入口，doc 是文档出口)
注释示例：

/**
 * @api {get} /user/:id Read data of a User
 * @apiVersion 0.3.0
 * @apiName GetUser
 * @apiGroup User
 * @apiPermission admin
 *
 * @apiDescription Compare Verison 0.3.0 with 0.2.0 and you will see the green markers with new items in version 0.3.0 and red markers with removed items since 0.2.0.
 *
 * @apiParam {String} id The Users-ID.
 *
 * @apiSuccess {String}   id            The Users-ID.
 * @apiSuccess {Date}     registered    Registration Date.
 * @apiSuccess {Date}     name          Fullname of the User.
 * @apiSuccess {String[]} nicknames     List of Users nicknames (Array of Strings).
 * @apiSuccess {Object}   profile       Profile data (example for an Object)
 * @apiSuccess {Number}   profile.age   Users age.
 * @apiSuccess {String}   profile.image Avatar-Image.
 * @apiSuccess {Object[]} options       List of Users options (Array of Objects).
 * @apiSuccess {String}   options.name  Option Name.
 * @apiSuccess {String}   options.value Option Value.
 *
 * @apiError NoAccessRight Only authenticated Admins can access the data.
 * @apiError UserNotFound   The <code>id</code> of the User was not found.
 *
 * @apiErrorExample Response (example):
 *     HTTP/1.1 401 Not Authenticated
 *     {
 *       "error": "NoAccessRight"
 *     }
 */

helmet

var express = require('express')
var helmet = require('helmet')

var app = express()

app.use(helmet())

cors

使用方式：

// 允许所有跨域请求
var express = require('express')
var cors = require('cors')
var app = express()

app.use(cors())

// 允许某路由的跨域请求
app.get('/products/:id', cors(), function (req, res, next) {
  res.json({msg: 'This is CORS-enabled for a Single Route'})
})

// 允许某些域的请求
var whitelist = ['http://example1.com', 'http://example2.com']
var corsOptions = {
  origin: function (origin, callback) {
    if (whitelist.indexOf(origin) !== -1) {
      callback(null, true)
    } else {
      callback(new Error('Not allowed by CORS'))
    }
  }
}

app.get('/products/:id', cors(corsOptions), function (req, res, next) {
  res.json({msg: 'This is CORS-enabled for a whitelisted domain.'})
})

// 允许 GET/POST 以外的请求
app.options('/products/:id', cors()) // enable pre-flight request for DELETE request
app.del('/products/:id', cors(), function (req, res, next) {
  res.json({msg: 'This is CORS-enabled for all origins!'})
})

// 对所有路由允许
app.options('*', cors()) // include before other routes

compression

使用方式：

var compression = require('compression')
var express = require('express')

var app = express()
app.use(compression({filter: shouldCompress}))

function shouldCompress (req, res) {
  if (req.headers['x-no-compression']) {
    // don't compress responses with this request header
    return false
  }

  // fallback to standard filter function
  return compression.filter(req, res)
}

response-time

使用方式：
该中间件将响应时间写在响应头 X-Response-Time 中

var express = require('express')
var responseTime = require('response-time')

var app = express()
// 统计响应进入该中间件到写完响应头的毫秒数
app.use(responseTime())

express-validator

验证规则

// 初始化
app.use(expressValidator())
// this line must be immediately after any of the bodyParser middlewares!

// 检查参数是否符合标准
req.check('testparam', 'Error Message').notEmpty().isInt()

// 将参数转化为
req.sanitize('postparam').toBoolean()

// 返回验证结果
req.getValidationResult().then(function(result) {
  // do something with the validation result
})

pm2

pm2 start app.js --name="api" # Start application and name it "api"
pm2 stop all                  # Stop all apps
pm2 logs                      # Display logs of all apps
pm2 web     后访问     http://localhost:9615/        # 查看系统状态