Migrate framework from express4 to koa2

[Kimi-Gao]

Express vs. Koa

1. http://javascript.ruanyifeng.com/nodejs/koa.html
2. http://koacn.com/
3. http://koajs.com/
4. https://zhuanlan.zhihu.com/p/23525034
5. https://github.com/koajs/koa/blob/master/docs/koa-vs-express.md
6. Express和koa各有啥优缺点? 知乎
7. https://github.com/guo-yu/koa-guide
8. Release 5.0 expressjs/express#2237
9. https://expressjs.com/en/starter/installing.html
10. https://eggjs.org/zh-cn/tutorials/mysql.html

Koa Middleware

https://github.com/koajs/koa/wiki
https://www.npmjs.com/package/koa-middlewares

Demo

https://github.com/superalsrk/koa2-boilerplate

Authorization

https://github.com/rkusa/koa-passport
https://github.com/jaredhanson/passport-local
https://github.com/koajs/jwt
https://github.com/auth0/node-jsonwebtoken
http://mp.weixin.qq.com/s/PgjBS2a2AKbjssVHyC2Dqw
koajs/session#20
https://github.com/hiddentao/koa-session-mongo
https://github.com/jdesboeufs/connect-mongo

Router

https://github.com/alexmingoia/koa-router

Others

https://github.com/functionscope/Node-Excel-Export

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