@forrestjs/core

ForrestJS helps you build a Modular JavaScript Application where you can (almost) forget about the infrastructure and FOCUS ON YOUR BUSINESS VALUE.

Install & Setup

npm add @forrestjs/core

Quick Code Example

const forrest = require('@forrestjs/core');
const fastify = require('@forrestjs/service-fastify');

forrest.run({
  // Add ForrestJS wrappers to famous and useful libraries
  services: [fastify],

  // Integrate your Business Logic with the running services
  features: [{
    target: '$FASTIFY_ROUTE',
    handler: {
      method: 'GET',
      url: '/',
      handler: async () => 'Hello World',
    },
  }],

  // Provide configuration to Services and Features
  settings: {
    fastify: {
      port: '8080'
    }
  }
]);

Vocabulary

ForrestJS Extensions

Extensions are at the very core of any ForrestJS Application. You can create or implement (register) extensions, depending on what you want to achieve.

When you create a ForrestJS Feature, you register extensions in order to provide custom business logic to existing Services (and Features).

EXAMPLE: You can register a new extension to $FASTIFY_ROUTE to provide a new Fastify route definition in your app.

When you create a new ForrestJS Service, you create new extensions as so to allow further specialization of your logic.

EXAMPLE: When your Postgres connection is established, you create a new extension so that other Features can run their initialization SQL queries.

ForrestJS Feature

A ForrestJS Feature is a package of Extensions that serve the same goal.

EXAMPLE: you can pack together a few $FASTIFY_ROUTE extensions into a Feature called "static-pages".

Such Feature has the goal to provide generic information to the website visitor.

ForrestJS Service

A ForrestJS Service implements a generic piece of business logic that should extended by some Features in order to provide real user value.

EXAMPLE: service-pg keeps an active connection pool towards a PostgreSQL database.

But without some Features that actually use it to run some SQL queries, it doesn't really do much for the end user.

Services are often thin wrappers around existing NPM Modules such Fastify or Node Postgres.

ForrestJS App

A ForrestJS App is a composition of Services and Features that provide some kind of User value.

App Manifest

We call "App Manifest" the entry point of a ForrestJS App (usually src/index.js).

This piece of code is mostly declarative and implements some specific responsibilities:

1. Validate the App's Environment
2. Provide configuration to Services and Features
3. Compose the App with lists of Services and Features
4. Handle boot errors

Service (or Feature) Manifest

We call "Service or Feature Manifest" the entry point of a ForrestJS Service or Feature. (usually: src/(services|features)/xxx/index.js).

This piece of code is mostly declarative and implements some specific responsibilities:

1. Register all the Extensions that are implemented by the Service/Feature
2. Declare new Extension's Targets for new Extensions provided by the Service/Feature

App Boot Lifecycle