@hawkstow/sfr NPM

Single File Router (SFR)

Overview

SFR allows the declaration of services including its controllers, handlers and validators in one single file.

Featuring a configurable Inversion of Control pattern for dependency libraries, It allows developers to easily inject dependencies on either handlers or controllers for convenient and easy access.

Due to it's self-contained and structured format, The SFR has allowed for the development of several extensions such as:

OpenAPI Service Translator
```
	`A plugin which also uses API-Bundler's ability to extract metadata from individual SFRs
```
It's main purpose is to translate and create service-level documentation which follows the OpenAPI Standard, this essentially opens up doors to extensive tooling support, instrumentation, automated endpoint testing, automated documentation generation, just to name a few.`

UAC - ACM Self-Registration Scheme

	`The in-house API-Bundler was designed to extract useful information from individual SFRs, termed service-artifacts, they are reported to a centralized authority through the well-documented UAC - ACM Self-Registration Scheme, this is prerogative to the grand scheme of Resource Administration.`

Structure

A regular SFR is composed of the following objects

Object Name	Description
CFG	configuration information relayed to the API-bundler (service-parser).
Validators	POJO representation of what values are allowed for each endpoint.
Handlers	Express middlewares which acts as the main logic block for each endpoint.
Controllers	Functions that execute calls to the database.

Usage

import sfr from "@hawkstow/sfr";
import express from "express";

const api_path = "api";
const doc_path = "docs";

const app = express();

/*
	Note: 
	SFR Bundler will look for two folders, named "rest" and "ws" inside the "path". 
	The placement of SFRs define the protocol that they'll use. 
	`
	i.e:rest SFRs reside within "rest", websocket SFRs reside in "ws".
*/

sfr({
  root : "dist",   //Specifies the working directory
  path : api_path, //Specifies the API directory i.e: where SFR files reside
  out  : doc_path  //Specifies the directory for the resulting OAS documents
}, app);

Error-Handling

The library automatically handles errors on both handlers and controllers, however, care must be taken on how error-handling is done by the developer, the following table illustrates what error-handling styles are allowed for both cases.