Tutorial: Flitter Core

libflitter is the core package that runs Flitter. Flitter's initialization structure is broken into individual bits called units, and these units are called one after the other to launch the application.

Each unit contains a function that, when called, initializes that particular unit. This function sets up the Unit's resources. However, the primary work of units are as services. Every unit provides some service that you can require in the rest of the injectable classes.

Injecting Services

You can require the instantiated module:libflitter/Unit~Unit services in other injectable classes (e.g. controllers/models/middleware) by adding their service name to the static services getter on the injectable class. For example, to access an instance of the module:libflitter/config/ConfigUnit~ConfigUnit service (to access app configs), we would request the configs service:

const { Model } = require('flitter-orm')

class MyAppModel extends Model {
	static get services() {
		return [...super.services, 'configs'] // It's important to keep the services required by parent classes in this array
	}

	// ... other code ...

	app_name() {
		return this.configs.get('app.name')
	}
}

Here, we overloaded the services property on the Model, which is provided by module:flitter-di/src/Injectable~Injectable to include the configs service in addition to the other services requested by parent classes.

This is the standard way of injecting services into other classes in Flitter.

Service Name Cheatsheet

Here are the names and service classes for common services provided by first-party Flitter modules. This list is not exhaustive, nor are all of these services installed with Flitter by default, but these are some of the most common ones: