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Version: 2.10.2 (latest)

Architecture Overview

FoalTS is a framework for creating server-side Node.js applications. It is written in TypeScript, a typed superset of JavaScript that provides advanced development tools and the latest language features.

FoalTS architecture is organized around three main components: controllers, services and hooks.

Controllers

Controllers are classes instantiated as singletons. Their methods process the incoming HTTP requests.

import { Get, HttpResponseOK } from '@foal/core';

class AppController {

@Get('/')
index() {
return new HttpResponseOK('Hello world!');
}

}

Services

Services are also classes instantiated as singletons. They are used by the controllers (or hooks) to perform specific tasks.

import { dependency, Get, HttpResponseOK } from '@foal/core';

class FormatService {
withDate(message: string): string {
return `${new Date()} - ${message}`;
}
}

class AppController {
@dependency
format: FormatService;

@Get('/')
index() {
const message = this.format.withDate('Hello world!');
return new HttpResponseOK(message);
}

}

Hooks

Hooks are small functions that add extra logic before or after the execution of a controller method.

import { Get, HttpResponseOK } from '@foal/core';
import { JWTRequired } from '@foal/jwt';

class AppController {

@Get('/')
@JWTRequired()
index() {
return new HttpResponseOK('Hello world!');
}

}

A Simple Application

Controllers may have sub-controllers. Hooks can be attached to the controllers or their methods.

Here's an example of what a FoalTS application may look like.

import { Context, controller, Get, HttpResponseNotFound, HttpResponseOK, Log } from '@foal/core';
import { JWTRequired } from '@foal/jwt';

@JWTRequired()
class ApiController {
private products = [
{ id: 1, name: 'phone' },
{ id: 2, name: 'computer' },
]

@Get('/products')
listProducts() {
return new HttpResponseOK(this.products);
}

@Get('/products/:id')
getProduct(ctx: Context) {
const product = this.products.find(
p => p.id === parseInt(ctx.request.params.id, 10)
);

if (!product) {
return new HttpResponseNotFound();
}

return new HttpResponseOK(product);
}
}

@Log('Receiving a request...')
class AppController {
subControllers = [
controller('/api', ApiController)
];

@Get('/')
index() {
return new HttpResponseOK('Welcome!');
}
}

Request Lifecycle