Structured Development in PHP

Author ID: VA035840

1. Introduction

This document outlines best practices for organizing PHP code in a maintainable and scalable way. Structured development improves readability, reusability, and long-term stability of your application.

2. File and Directory Organization

  • /config – Configuration files (database, paths, constants)
  • /lib – Reusable libraries and helper functions
  • /modules – Feature-specific business logic
  • /public – Entry points (index.php, assets)
  • /templates – HTML layouts and partials

3. Separation of Concerns

Avoid mixing HTML and PHP logic. Keep database access, data processing, and presentation in distinct layers. This makes debugging and updating easier.

4. Example: Simple Config and Bootstrap

// config/db.php
define('DB_HOST', 'localhost');
define('DB_USER', 'root');
define('DB_PASS', '');
define('DB_NAME', 'app_db');
  
// public/index.php
require_once '../config/db.php';
require_once '../lib/db_connect.php';
require_once '../modules/home.php';
  

5. Function Reuse and Libraries

Common utilities such as form validation, string formatting, and error logging should be abstracted into separate library files for reuse across modules.

6. Error Handling Strategy

  • Enable strict error reporting during development
  • Use try-catch blocks around risky operations (e.g., DB connection)
  • Log errors to file and show generic messages to users

7. Conclusion

Structured PHP development is not about frameworks, but about discipline. By consistently separating logic, managing files properly, and using modular practices, even a plain PHP project can remain clean, safe, and scalable over time.