Enhancement: Code Reusability: Repetitive Code Patterns Across the Codebase - Issue 9

[HTSagara]

Overview

The code base had some redundancy. In this PR I tried to reduce it as much as possible. Most of the changes were made in the server side.

Backend

Utils folder

In the utils folder I added three new files asyncHandler.js, dbUtils.js, and responseHandler.js

asynceHandler.js

This file exports a function called asyncHandler that wraps asynchronous route handlers in an Express.js application. It ensures that any errors occurring in asynchronous code are caught and handled properly. If an error occurs, it logs the error message and responds with a 500 Internal Server Error, or with a custom error message if provided.

// utils/asyncHandler.js
const asyncHandler =
  (fn, errorMessage = "Internal server error") =>
  (req, res, next) =>
    Promise.resolve(fn(req, res, next)).catch((error) => {
      console.error(`Error: ${error.message}`);
      res.status(500).json({ error: errorMessage });
    });

module.exports = asyncHandler;

This function was implemented in most of the routes.

dbUtils.js

This file provides utility functions for interacting with the database:

• getBuyerById: Retrieves a buyer's information from the Buyers table by their Buyer_ID.
• getTransactionsByBuyerId: Fetches all transactions associated with a given buyer from the Transactions table, identified by their Buyer_ID. Both functions use PostgreSQL queries to interact with the database.

// /utils/dbUtils.js
const pool = require("../config/db");

const getBuyerById = async (buyerId) => {
  const query = "SELECT * FROM Buyers WHERE Buyer_ID = $1";
  const { rows } = await pool.query(query, [buyerId]);
  return rows.length > 0 ? rows[0] : null;
};

const getTransactionsByBuyerId = async (buyerId) => {
  const query = "SELECT * FROM Transactions WHERE Buyer_ID = $1";
  const { rows } = await pool.query(query, [buyerId]);
  return rows;
};

module.exports = {
  getBuyerById,
  getTransactionsByBuyerId,
};

responseHandler.js

This file provides utility functions to handle HTTP responses:

• send404: Sends a 404 Not Found response with a custom error message.
• send500: Sends a 500 Internal Server Error response with a custom error message.
• sendSuccess: Sends a 200 OK response with a custom success data payload. These functions are used to standardize response handling in an Express.js application.

// utils/responseHandler.js
const send404 = (res, message) => res.status(404).json({ error: message });

const send500 = (res, message) => res.status(500).json({ error: message });

const sendSuccess = (res, data) => res.status(200).json(data);

module.exports = {
  send404,
  send500,
  sendSuccess,
};

Frontend

For the frontend the only change that I made was the suggested one in the issue description. I couldn't find the routes to create a new user so I could not login and test the rest of the frontend. So, I decided to stick with the proposed change.

AdminDashboard.jsx

I created the reusable button component that accepts the prop.

// Reusable ButtonLink component
const ButtonLink = ({ to, text }) => {
  return (
    <Link to={to} className="mr-4">
      <button className="px-4 py-2 bg-blue-500 text-white rounded hover:bg-blue-600">
        {text}
      </button>
    </Link>
  );
};

[vercel[bot]]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
dbms-project	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Oct 18, 2024 10:09pm

[manascb1344]

Thanks for the awesome PR @HTSagara Really appreciate your contribution!