php

PHP Coding Standards and Best Practices

Overview

This document outlines the coding standards and best practices for PHP development, focusing on modern PHP principles applicable across PHP versions 7.4 and later.

Code Style

Naming Conventions

• Classes: Use PascalCase (e.g., UserProfile, DatabaseConnection)
• Methods/Functions: Use camelCase (e.g., getUserData(), connectToDatabase())
• Variables: Use camelCase (e.g., $userData, $databaseConfig)
• Constants: Use UPPERCASE with underscores (e.g., MAX_LOGIN_ATTEMPTS, DEFAULT_TIMEOUT)
• Private/Protected Properties: Prefix with underscore (e.g., $_privateProperty)
• Namespaces: Use PascalCase (e.g., App\Services\Authentication)
• Interfaces: Suffix with Interface (e.g., RepositoryInterface, CacheInterface)
• Traits: Suffix with Trait (e.g., LoggableTrait, SerializableTrait)
• Abstract Classes: Prefix with Abstract (e.g., AbstractController, AbstractRepository)

Code Formatting

• Use 4 spaces for indentation, not tabs
• Line length should generally not exceed 120 characters
• Use one blank line to separate logical blocks of code
• Place opening braces on the same line for control structures
• Place opening braces on the next line for classes and methods
• Include a space after control structure keywords and before parentheses
• Use explicit visibility (public, protected, or private) for class methods and properties
• Use trailing commas in multiline arrays
• Avoid unnecessary parentheses

// Good
if ($condition) {
    // code
} else {
    // code
}

// Good
public function methodName($param1, $param2)
{
    // Method body
}

// Good
$array = [
    'key1' => 'value1',
    'key2' => 'value2',
];

PHP Standards

Use Modern PHP Features

• Prefer type declarations (scalar types, return types, nullable types)
• Use native PHP functions over custom implementations when available
• Use appropriate data structures (arrays, objects, generators)
• Leverage PHP's built-in array functions (array_map, array_filter, etc.)
• Use anonymous functions and arrow functions for simple callbacks