Introduction to DeNO

• deno Official website ：https://deno.land/
• deno Chinese Translation Network ：https://deno-cn.vercel.app/

What is? Deno?

Node.Js author Ryan Dahl stay 2018 year 8 month 23 Japan released the first version of v0.1.0 Of deno, Why? Ryan Dahl To change your life and create a new runtime ？

1. Too many and incompatible module import rules ：ES modular 、CommonJs…
2. node_modules Black holes
3. Yes callback ES5、Promise ES6 and async/await( be based on Promise)ES7 Two ways of writing
4. Too many tools （webpack、vite、babel、tsc…）

• Ruan Yifeng is right deno Explanation ：deno Explain

Learning cost

• Study deno More concerned must be language ,deno Our position is still runtime Runtime , But in particular, it is Typescript、JavaScript Runtime , That is, it can run directly Typescript( The internal will, however ts Translate it into js) and Javascript

• So using node My classmates can ECMAscript Grammatically seamlessly migrate to node

• Learn something ：

deno Tool command ： Because there is no npm, Package management is deno Helping us
deno Some special case Syntax ： Because the best use promise structure , less .

for await(const conn of listener) {
    
	// ...
}

• Work : because deno only v1.18.2 edition , You can't find it if you want to try deno Related development

If you're looking for a job , It's better to learn node, To engage in enterprise level micro service development, we must learn Typescript, At present, very thoughtful frameworks are being used , Such as support Ioc DI、Aop… Framework midwayjs、nestjs、darukjs、malagujs, If you like it very much serverless Recommended malagujs

The enterprise level framework is deno Doesn't exist in ？ There is , Look at ecology

• ecology

  • At present, high-quality deno library ：https://github.com/hylerrix/awesome-deno-cn

  • Support deno The source of discovery （ I'm not sure. It must be deno Of , It also supports node）：https://www.skypack.dev/

  • The official discovery source （ Certain support deno）：https://deno.land/x

• Think about it ：node Capable web application 、 structure vue、react Project tools

1. web Application Library / frame ：
   Imitation koa Of ：https://github.com/ako-deno/ako
   Imitation express Of ：https://github.com/cmorten/opine
   suffer nest Enlightening typescript library ( In development …)：https://github.com/SampaioLeal/destjs

2. Build a library of front-end projects / frame ：
   suffer next.js(react) Enlightening SSR frame ：https://alephjs.org/docs
   stay deno Build running under Vue2/3 Tools for ：https://github.com/mggower/vno

Why? nest We are not going to migrate to deno?

Officials are going to see deno Make plans for the development of issue：https://github.com/nestjs/nest/issues/4495

Original words ：“Deno Not mature enough , You can't even try to NestJS Transplant to it . I suggest we first look at “ smaller ” Of Node.js Project how it develops with —— Whether they are transplanted or rewritten . According to the trend set by the community and “ standard ”, We will consider working with NestJS Move together .”

deno With Compat Mode compatible node.js, But not supported typescript,issue：https://github.com/nestjs/nest/issues/8867

Because compatibility does not support typescript, That's equivalent to writing the project well and using deno run , It doesn't make much sense

• Thoughts and feelings
  What we need most now is to settle down and use typescript and node Write some tools , For example, some Vue、React、Nestjs Use the scaffold template to seal the scaffold .

as for deno If it gets better and better with its ecology , It's not too late to get to know him and use it ,deno To be honest, there are still many ways to go , Because it just came out, so many serverless Is not supported , Unless you customize deno Environmental Science , At present, there is basically no work , And enterprise level framework deno It's not perfect .

Generally speaking, at present deno There is no overwhelming reason for me to use , Instead, it brings me some shortcomings , Such as ： ecology , No resources npm Clear central source, etc ,deno A small dinosaur in a developing stage , I hope one day , You can also experience its style in the enterprise .

• deno analysis ：
  We don't need deno：https://segmentfault.com/a/1190000040122104

• deno course ：
  Deno Introduction Manual ：
  https://chinese.freecodecamp.org/news/the-deno-handbook-with-examples/

• great Deno Introduction and actual combat ：
  https://juejin.cn/post/6844904162321252360

• Asynchronous function in deno Timeout in ：
  https://medium.com/deno-the-complete-reference/timeout-for-async-functions-in-deno-52cee16e6e92