L2jLiga / fastify-decorators

Set of Typescript decorators to build Fastify server with controllers, services and hooks

Framework aimed to provide useful TypeScript decorators to implement controllers, services and request handlers, built with Fastify.

Benefits

• Fastify compatible - Built with Fastify and supports all its features and plugins
  • JSON Schema validation - Build JSON Schemas to validate and speedup your requests and replies
  • High performance - Framework adds as less overhead to Fastify as it can
• Highly customizable - Create your controllers, services and their methods as you wish
• 100% TypeScript - Written in TypeScript and comes with all the required typings
• Plugins - Library provides APIs to extend its functionality
  • Simple DI - Provides simple Dependency Injection interface to bind your services
  • TypeDI - Provides integration with TypeDI

Documentation

• Getting started
• Bootstrapping
• Controllers
• Request Handlers
• Testing
• Plugins Development
• Migration guide (V4)

Fastify versions support

Fastify Decorators	Fastify
1.x	2.x
2.x	2.x
< 3.12.x	3.x
>= 3.12.x	3.x & 4.x
4.x	4.x

Alternatives

• NestJS - A progressive Node.js framework for building efficient, reliable and scalable server-side applications.
• Fastify Resty - Modern and declarative REST API framework for superfast and oversimplification backend development, build on top of Fastify and TypeScript.

Getting started

Hello! Thank you for checking out fastify-decorators!

This documents aims to be gentle introduction to the fastify-decorators and its usages.

Prerequisites

• Typescript
• Fastify
• typings for NodeJS (@types/node package installed)

Install

Install with npm

npm i fastify-decorators --save

Install with yarn

yarn add fastify-decorators

Additional TypeScript configuration

Fastify-decorators requires experimentalDecorators feature to be enabled. For this you need to update your TypeScript config:

tsconfig.json:

{
  "compilerOptions": {
    "experimentalDecorators": true
  }
}

Note: if you struggle which target please refer to table below:

Node version	target
14.x	es2020
16.x	es2021
18.x	es2022

fastify-decorators itself use "target": "es2018" to support NodeJS 10+ (see Node.js ES2018 Support).

Your first server

Request handler way

Let's write your first server with request handler:

Project structure:

 ├── index.ts
 ├── handlers
 │    └── first.handler.ts
 └── tsconfig.json

index.ts:

import { bootstrap } from 'fastify-decorators';

// Require the framework and instantiate it
const instance = require('fastify')();

// Register handlers auto-bootstrap
instance.register(bootstrap, {
  // Specify directory with our handler
  directory: new URL(`handlers`, import.meta.url),

  // Specify mask to match only our handler
  mask: /\.handler\./,
});

// Run the server!
instance.listen(3000);

handlers/first.handler.ts:

import { GET, RequestHandler } from 'fastify-decorators';

@GET({
  url: '/hello',
})
export default class FirstHandler extends RequestHandler {
  async handle() {
    return 'Hello world!';
  }
}

Controllers way

fastify-decorators also provides way to build controllers with multiple handlers:

Project structure:

 ├── index.ts
 ├── controllers
 │    └── first.controller.ts
 └── tsconfig.json

index.ts:

import { bootstrap } from 'fastify-decorators';

// Require the framework and instantiate it
const instance = require('fastify')();

// Register handlers auto-bootstrap
instance.register(bootstrap, {
  // Specify directory with our controllers
  directory: new URL(`controllers`, import.meta.url),

  // Specify mask to match only our controllers
  mask: /\.controller\./,
});

// Run the server!
instance.listen(3000);

controllers/first.controller.ts:

import { Controller, GET } from 'fastify-decorators';

@Controller({ route: '/' })
export default class FirstController {
  @GET({ url: '/hello' })
  async helloHandler() {
    return 'Hello world!';
  }

  @GET({ url: '/goodbye' })
  async goodbyeHandler() {
    return 'Bye-bye!';
  }
}

Also, we need to enable experimentalDecorators feature in our TypeScript config

tsconfig.json:

{
  "compilerOptions": {
    "experimentalDecorators": true
  }
}

Build and run server

After all our files done we have to build server before we can run it:

1. Add to our package.json script to build server:

   "scripts": {
     "build": "tsc"
   }
   

2. Run build script With npm:

   npm run build
   

   with yarn:

   yarn build
   

3. Start server

   node index.ts
   

Awesome, that was easy.

License

This project licensed under MIT License