MCP WordPress Server

# Architecture Guide This guide explains the system architecture and design patterns used in the MCP WordPress Server. ## 🏗️ Overall Architecture The MCP WordPress Server follows a modular, layered architecture designed for scalability, maintainability, and extensibility. ```text ┌─────────────────────────────────────────────────────────────┐ │ MCP Server Layer │ ├─────────────────────────────────────────────────────────────┤ │ Tool Registry │ ├─────────────────────────────────────────────────────────────┤ │ Posts │ Pages │ Media │ Users │ Comments │ Taxonomies │... │ ├─────────────────────────────────────────────────────────────┤ │ WordPress Client Layer │ ├─────────────────────────────────────────────────────────────┤ │ Auth Manager │ Request Manager │ Cache Manager │ Metrics │ ├─────────────────────────────────────────────────────────────┤ │ WordPress REST API │ └─────────────────────────────────────────────────────────────┘ ``` ## 🎯 Design Principles ### 1. Composition Over Inheritance - **Manager Pattern**: Client functionality split into focused managers - **Dependency Injection**: Tools receive client instances for testability - **Single Responsibility**: Each class has one clear purpose ### 2. Type Safety First - **100% TypeScript**: Complete type coverage for all APIs - **Strict Mode**: Enabled for maximum type safety - **Zod Validation**: Runtime validation matching compile-time types ### 3. Modular Architecture - **Pluggable Tools**: Easy to add new WordPress management tools - **Manager System**: Focused, replaceable components - **Clean Interfaces**: Well-defined boundaries between layers ### 4. Performance by Design - **Intelligent Caching**: Multi-layer caching with invalidation - **Request Optimization**: Batching and deduplication - **Resource Management**: Memory and connection pooling ## 🔧 Core Components ### MCP Server (`src/index.ts`) **Purpose**: Main entry point implementing the Model Context Protocol **Key Features**: - Tool registration and discovery - Request routing and handling - Multi-site configuration support - Error handling and logging **Architecture Pattern**: Facade + Factory ```typescript class MCPWordPressServer { private toolRegistry: ToolRegistry; private clients: Map<string, WordPressClient>; constructor(config: Config) { this.toolRegistry = new ToolRegistry(); this.clients = this.initializeClients(config); } } ``` ### WordPress Client (`src/client/WordPressClient.ts`) **Purpose**: Primary interface to WordPress REST API **Architecture Pattern**: Composition + Manager Pattern ```typescript class WordPressClient { private authManager: AuthenticationManager; private requestManager: RequestManager; private cacheManager: CacheManager; constructor(config: ClientConfig) { this.authManager = new AuthenticationManager(config); this.requestManager = new RequestManager(config); this.cacheManager = new CacheManager(config); } } ``` **Manager Responsibilities**: - **AuthenticationManager**: Handle all authentication methods - **RequestManager**: HTTP operations, retries, rate limiting - **CacheManager**: Intelligent caching with invalidation ### Tool System (`src/tools/`) **Purpose**: WordPress management functionality exposed as MCP tools **Architecture Pattern**: Class-based Tools with Dependency Injection ```typescript export class PostTools { constructor(private client: WordPressClient) {} async createPost(params: CreatePostParams): Promise<PostResult> { return toolWrapper(this.client, "create_post", params, async () => { const validatedParams = createPostSchema.parse(params); return await this.client.posts.create(validatedParams); }); } } ``` **Tool Categories**: - **Content Tools**: Posts, Pages, Media (18 tools) - **User Management**: Users, Comments (13 tools) - **Site Management**: Taxonomies, Settings, Auth (23 tools) - **Performance**: Cache, Monitoring (10 tools) ### Performance System (`src/performance/`) **Purpose**: Real-time performance monitoring and optimization **Architecture Pattern**: Observer + Strategy Pattern ```typescript class PerformanceMonitor { private collectors: MetricsCollector[]; private analytics: PerformanceAnalytics; collect(metric: Metric): void { this.collectors.forEach((collector) => collector.collect(metric)); this.analytics.analyze(metric); } } ``` **Components**: - **MetricsCollector**: Gather performance data - **PerformanceAnalytics**: Analyze trends and patterns - **AlertSystem**: Notify on performance degradation ### Cache System (`src/cache/`) **Purpose**: Intelligent multi-layer caching for performance **Architecture Pattern**: Decorator + Strategy Pattern ```typescript class CacheManager { private strategies: Map<string, CacheStrategy>; async get<T>(key: string): Promise<T | null> { const strategy = this.strategies.get(this.getStrategyKey(key)); return await strategy.get(key); } } ``` **Cache Layers**: - **Memory Cache**: Fast in-memory storage - **Site-Specific Cache**: Isolated cache per WordPress site - **Invalidation Logic**: Smart cache invalidation on updates ## 🔒 Security Architecture ### Input Validation Pipeline ```text User Input → Zod Schema → Sanitization → WordPress API ↓ ↓ ↓ Type Safety SQL Injection XSS Protection Prevention ``` ### Authentication Flow ```text Client Request → Auth Manager → WordPress API ↓ ↓ Token Validation Permission Check ``` **Security Layers**: 1. **Input Validation**: Comprehensive Zod schemas 2. **Authentication**: Multiple secure methods 3. **Authorization**: WordPress permission system 4. **Transport Security**: HTTPS enforcement 5. **Rate Limiting**: API abuse prevention ## 🚀 Request Flow ### Standard Tool Execution ```text MCP Request → Tool Registry → Tool Class → Client Manager → WordPress API ↓ ↓ ↓ ↓ Validation Parameter Authentication HTTP Request Processing ``` ### Cached Request Flow ```text MCP Request → Cache Check → [Cache Hit] → Cached Response ↓ ↓ Cache Miss WordPress API → Cache Store → Response ``` ## 📊 Data Flow ### Configuration Loading ```text Environment Variables → Config Validation → Client Initialization Multi-Site Config ↗ ↓ Tool Registration ``` ### Error Handling ```text Error Occurrence → Error Classification → User-Friendly Message ↓ ↓ Logging System MCP Response ``` ## 🧪 Testing Architecture ### Test Strategy **Unit Tests**: Individual component testing - Mock external dependencies - Test business logic in isolation - Focus on edge cases and error conditions **Integration Tests**: Multi-component testing - Real WordPress API connections - End-to-end tool functionality - Authentication method validation **Contract Tests**: API compatibility testing - WordPress REST API changes - MCP protocol compliance - Backward compatibility verification ### Test Structure ```text tests/ ├── unit/ # Component isolation tests ├── integration/ # Multi-component tests ├── security/ # Security validation tests ├── performance/ # Performance regression tests └── property/ # Property-based tests ``` ## 🔄 Build & Deployment ### Build Pipeline ```text TypeScript Source → Compilation → Bundling → Distribution ↓ ↓ ↓ Type Check Optimization NPM Package Docker Image ``` ### Release Process ```text Commit → CI/CD Pipeline → Tests → Security Scan → Publishing ↓ ↓ ↓ ↓ Conventional All Pass Vulnerability NPM + Docker Commits Free + GitHub ``` ## 📈 Performance Optimizations ### Caching Strategy **Multi-Layer Caching**: - **L1 Cache**: In-memory (fastest) - **L2 Cache**: Site-specific (isolated) - **L3 Cache**: Persistent (cross-session) **Cache Invalidation**: - **Time-based**: TTL expiration - **Event-based**: Content update invalidation - **Manual**: Administrative cache clearing ### Request Optimization **Batching**: Group related requests **Deduplication**: Eliminate duplicate requests **Connection Pooling**: Reuse HTTP connections **Compression**: Reduce payload size ## 🔮 Extensibility ### Adding New Tools 1. **Create Tool Class**: Follow existing patterns 2. **Define Parameters**: Zod schema validation 3. **Implement Logic**: Use client managers 4. **Add Tests**: Unit and integration tests 5. **Register Tool**: Add to tool registry ### Adding New Managers 1. **Extend BaseManager**: Inherit common functionality 2. **Implement Interface**: Define manager contract 3. **Add to Client**: Compose into main client 4. **Test Integration**: Verify with existing tools ### Adding New Authentication 1. **Extend AuthenticationManager**: Add new method 2. **Implement Strategy**: Handle auth flow 3. **Add Configuration**: Support new config options 4. **Test Security**: Validate security properties ## 🔍 Monitoring & Observability ### Metrics Collection **Performance Metrics**: - Request latency and throughput - Cache hit rates and efficiency - Memory usage and garbage collection **Business Metrics**: - Tool usage patterns - Authentication success rates - Error rates and types ### Logging Strategy **Structured Logging**: JSON format for parsing **Log Levels**: DEBUG, INFO, WARN, ERROR **Contextual Information**: Request IDs, user context **Security Logging**: Authentication events, suspicious activity ## 📚 Further Reading - **[API Reference](API_REFERENCE.md)** - Complete technical API documentation - **[Testing Guide](TESTING.md)** - Test suite and best practices - **[Security Guidelines](SECURITY_DEVELOPMENT.md)** - Security best practices - **[Performance Guide](PERFORMANCE_DEVELOPMENT.md)** - Performance optimization --- **Understanding the architecture?** This foundation enables the system's reliability, performance, and extensibility. Each component is designed to be testable, maintainable, and scalable.