How to successfully decouple your frameworks from your business logic to improve testing and maintainability

Caio Tony — Fri, 18 Feb 2022 14:24:41 +0000

Hi Folks, Howdy?

have you ever heard about God Objects? never? already? however, let me explain what a hell is this:

In object-oriented programming, a God Object (sometimes also called an Omniscient or All-knowing object) is an object that references a large number of distinct types, has too many unrelated or uncategorized methods, or some combination of both. The God object is an example of an anti-pattern and a code smell. definition from wikipedia

Turn your attention to the bolded sentence, this is the main problem of God objects and also the issue that turns it into anti-pattern/principle cause it notably is opposed to single-responsibility principle. let's look to a example:

import { postModel } from "../models/post";
import { Post } from "../types"
import express from "express";
import { Request, Response } from express
const router = express.Router()


class controller {
  static async handle (request: Request, response: Response): Promise<Post[]> {

   try{
    if (request["query"] == {}) {
      return response.status(400).json({
        statusCode: 400,
        message: "must inform query parameters"
      })
    }
    const { query } = request;
    const posts: Promise<Post[]> = await postModel.find(query).lean();

    return response.status(201).json(posts)
  }catch(err) {
    return response.status(500).json({
      statusCode: 500,
      message: "internal server error"
    })
  }

  }
}

router.get("/posts", controller.handle);

export controller;

DEV Community: Caio Tony

How to successfully decouple your frameworks from your business logic to improve testing and maintainability