npm i redis@3.0.2 -S

// src\config\envs\dev.js

module.exports = {
  // redis 连接配置
  redisConf: {
    port: '6379',
    host: '127.0.0.1',
    password: 'xiaowei123'
  },
}

// src\cache\index.js

const redisClient = require('../db/redis')

/**
 * redis set
 * @param {string} key key
 * @param {string|Object} val val
 * @param {number} timeout 过期时间，单位 s ，默认 1h
 */
function cacheSet(key, val, timeout = 60 * 60) {
  let formatVal
  if (typeof val === 'object') {
    formatVal = JSON.stringify(val)
  } else {
    formatVal = val
  }
  redisClient.set(key, formatVal)
  redisClient.expire(key, timeout)
}

/**
 * redis get
 * @param {string} key key
 */
function cacheGet(key) {
  const promise = new Promise((resolve, reject) => {
    redisClient.get(key, (err, val) => {
      if (err) {
        reject(err)
        return
      }
      if (val == null) {
        resolve(null)
        return
      }

      try {
        resolve(JSON.parse(val))
      } catch (ex) {
        resolve(val)
      }
    })
  })
  return promise
}

module.exports = {
  cacheSet,
  cacheGet,
}

// src\db\redis.js

const redis = require('redis')
const { redisConf } = require('../config/index')

// 创建客户端
const { port, host, password } = redisConf
const opt = {}
if (password) {
  opt.password = password // prd 环境需要密码
}
const redisClient = redis.createClient(port, host, opt)
redisClient.on('error', err => {
  console.error('redis connect error', err)
})
// 运行 node src/db/redis.js 进行测试连接
redisClient.on('connect', () => {
  console.log('redis connect success')
  redisClient.set('foo', 'bar', redis.print) // => "Reply: OK"
  redisClient.get('foo', redis.print) // => "Reply: bar"
  redisClient.quit()
})

module.exports = redisClient

// src\routes\index.js
const router = require('koa-router')()
const packageInfo = require('../../package.json')
const testMysqlConn = require('../db/mysql2')
const ENV = require('../utils/env')
const { WorkModel } = require('../models/WorksModel')
const { cacheGet, cacheSet } = require('../cache/index')

// 测试数据库连接
router.get('/api/db-check', async (ctx) => {
  // 测试 mysql 数据库连接
  const mysqlRes = await testMysqlConn()

  // 测试 mongodb 数据库连接
  let mongodbConn
  try {
    mongodbConn = true
    await WorkModel.findOne()
  } catch (error) {
    mongodbConn = false
  }

  // 测试 Redis 连接
  cacheSet('name', 'biz editor sever OK - by redis')
  const redisTestVal = await cacheGet('name')

  ctx.body = {
    errno: 0,
    data: {
      name: 'biz editor server',
      version: packageInfo.version,
      ENV,
      mysqlConn: mysqlRes.length > 0,
      mongodbConn,
      redisConn: redisTestVal != null,
    }
  }
})

module.exports = router