构建自己的模块

你还可以引用一个对象来公开导出并持续将方法附加到该对象：

const auth = module.exports = {}
const config = require('../config')
const request = require('request')

auth.email = function (data, callback) {
  // Authenticate with an email address
}

auth.facebook = function (data, callback) {
  // Authenticate with a Facebook account
}

auth.twitter = function (data, callback) {
  // Authenticate with a Twitter account
}

auth.slack = function (data, callback) {
  // Authenticate with a Slack account
}

auth.stack_overflow = function (data, callback) {
  // Authenticate with a Stack Overflow account
}

要使用其中任何一个，只需像往常一样要求模块：

const auth = require('./auth')

module.exports = function (req, res, next) {
  auth.facebook(req.body, function (err, user) {
    if (err) return next(err)

    req.user = user
    next()
  })
}