⚙️ Backend Overview

This document provides a complete overview of the backend architecture, including the request lifecycle, folder structure, and code organization philosophy used throughout the application.

🔁 Request Lifecycle

Here’s what happens from the moment a request hits the server to when a response is returned:

  1. Router:
    • The Router class matches incoming HTTP requests to a defined route and applies any attached middleware.
  2. Middleware:
    • Middleware classes can intercept the request before it hits the controller. Examples include authentication checks, CSRF verification, etc.
  3. Controller:
    • If all middleware pass, the corresponding controller is invoked. The controller handles validation, business logic, and calls models as needed.
  4. Validation:
    • The Validator class checks that incoming data meets defined rules. Errors are returned as JSON responses if validation fails.
  5. Model Interaction:
    • Models handle all communication with the database. Queries are abstracted behind model methods.
  6. Response:
    • A response is returned using the Response class, typically as a JSON object with a proper HTTP status code.
App/
├── Controllers/     # Request handlers for your routes
├── Core/            # Core classes (Router, Request, Response, Validator, etc.)
├── Middleware/      # Middleware logic (e.g., AuthMiddleware)
├── Models/          # Database abstraction and queries
├── Views/           # (If applicable) for server-rendered pages
├── Config/          # Environment and configuration settings
database/
└── migrations/      # Table creation scripts with up/down methods
tests/
└── Unit/            # Unit tests
└── Feature/         # Integration tests
public/
└── index.php        # Entry point
.env.example         # Sample environment variables
.cardikit            # CLI tool

🧼Code Organization Philosophy

  • Explicit & Modular: Each class and file has one clear responsibility. Core logic is centralized, avoiding duplication.
  • Minimal Global State: No unnecessary globals. Data is passed explicitly to functions and constructors.
  • PSR-4 Autoloading: All classes are namespaced and autoloaded by Composer.
  • Validation First: Data is validated at the boundary (controllers), not deep inside the logic.
  • Testability: Classes are designed to be unit-tested. The system supports mocking and avoids hidden side effects.

🧽 Linting & Standards

  • PSR-12 for PHP code style
  • Consistent docblocks with @package, @since, and parameter annotations
  • Class names use PascalCase, file names match class names
  • Methods and variables use camelCase
  • Align multiline arrays and parameters for readability
  • Limit neting to 2-3 levels

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