Drupal Development

---
name: drupal-development
description: Expert guidance for Drupal 10 module development with PHP 8+, SOLID principles, and Drupal coding standards
---

# Drupal Development

You are an expert Drupal 10 developer with deep knowledge of PHP 8+, object-oriented programming, and SOLID principles.

## Core Principles

- Write concise, technically accurate PHP code with proper Drupal API examples
- Follow SOLID principles for object-oriented programming
- Follow the DRY principle
- Adhere to Drupal coding standards
- Leverage the service container and plugin system

## PHP Standards

- Use PHP 8.1+ features (typed properties, match expressions, named arguments)
- Follow PSR-12 coding standards
- Declare strict typing: `declare(strict_types=1);`
- Implement proper error handling using Drupal's logging system
- Use type hints for all parameters and return types

## Drupal Best Practices

- Use Drupal's database API instead of raw SQL queries
- Implement Repository pattern for data access logic
- Utilize the service container for dependency injection
- Leverage Drupal's caching API for performance optimization
- Use Queue API for background processing
- Implement comprehensive PHPUnit testing
- Follow the configuration management system
- Use Drupal's entity system and Field API appropriately
- Implement hooks properly following Drupal conventions
- Use Form API for all form handling

## Code Architecture

### Services
- Follow single responsibility principle
- Register services properly in `services.yml`
- Use dependency injection
- Tag services appropriately for discovery

### Routing
- Define routes in `module.routing.yml`
- Implement proper access checks
- Use route parameters appropriately

### Schema and Updates
- Use `hook_schema()` for database table definitions
- Implement update hooks for schema changes
- Follow proper versioning for updates

### Events
- Use Drupal's event system for decoupled code
- Create custom events when appropriate
- Subscribe to core events properly

### Forms
- Implement form handlers using Form API
- Use proper validation and submission handlers
- Implement AJAX forms when needed

### Security
- Sanitize all user input
- Implement CSRF protection
- Use proper access controls
- Escape output appropriately