node.js + express 完成登录接口功能

第一步创建文件并初始化

yarn init

第二步安装依赖 

yarn add express nodemon

nodemon 用于热更新
第三步创建功能文件 （bodyParser 已删除请忽略）

common/index.js 

const fs = require('fs');
// promisify 异步处理
const { promisify } = require('util');
const path = require('path');




const readFile = promisify(fs.readFile)





// 获取 json 数据
const getFileData = async (fileName) => {
  const filePath = path.join(__dirname, `../json/${fileName}.json`)
  const data = await readFile(filePath, 'utf-8')
  return JSON.parse(data)
}





module.exports = {
  getFileData
}

json/userData.json

[
  {
    "userName": "Fengchengzhi",
    "sex": "男",
    "age": 25,
    "mobile": 123456,
    "mailbox": "xxxxx",
    "password": "123456"
  },
  {
    "userName": "root",
    "sex": "男",
    "age": 25,
    "mobile": 123456,
    "mailbox": "xxxxx",
    "password": "123456"
  }
]

router/login.js

const express = require('express');
// 获取 json 数据
const { getFileData } = require('../common');


const router = express.Router();





// 登录
router.post('/api/login', async(req, res) => {
  global.isLogin = true
  // 获取所有用户信息
  const allUserInfo = await getFileData('userData')
  const { userName, password } = req.body
  const info = allUserInfo.find(item => item.userName == userName)
  if (!info) {
    res.json({
      code: 500,
      data: null,
      message: '用户不存在！'
    })
  } else {
    if (info.password !== password) {
      res.json({
        code: 500,
        data: null,
        message: '密码错误！'
      })
    } else {
      res.json({
        code: 200,
        data: info,
        message: '登录成功！'
      })
    }
  }
})





// 退出登陆
router.post('/api/loginOut', (req, res) => {
  global.isLogin = false
  res.json({
    code: 200,
    data: null,
    message: '退出登录成功！'
  })
})





module.exports = router;
 

index.js

const express = require('express');
const app = express();
const login = require('./router/login');
const menu = require('./router/menu');


// 登录状态
global.isLogin = false





// 解析 application/json 数据
app.use(express.json())
// 解析 application/x-www-form-urlencoded 数据
app.use(express.urlencoded())





// 登录拦截
app.all('*', (req, res, next) => {
  if (req.url !== '/api/login') {
    if (!global.isLogin) {
      return res.json({
        code: 304,
        data: null,
        message: '未登录！'
      })
    }
  }
  next()
})





// router
app.use('/', login);
app.use('/', menu);





app.listen(5000, () => {
  console.log('服务启动')
})

package.json

{
  "name": "node-api",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "dependencies": {"express": "^4.17.3",
    "nodemon": "^2.0.15"
  },
  "scripts": {
    "start": "nodemon index.js"
  }
}

启动 yarn start

测试结果 （注意这里的请求是做过跨域处理的）