DISTRIBUTED-SYSTEM

Microservices Architecture Implementation

This project implements all 22 microservice patterns described in MICROSERVICE-PATTERNS.MD using Rust and modern cloud-native technologies.

Project Structure

MICROSERVICES-ARCH/
├── gateway/              # API Gateway service
├── bff/                  # Backend-for-Frontend services
│   └── web-bff/          # Web-specific BFF
├── services/             # Core domain services
│   ├── user-service/     # User management service
│   └── order-service/    # Order processing service
├── shared/               # Shared libraries and models
├── messaging/            # Messaging infrastructure
├── observability/        # Tracing and metrics
├── security/             # Security utilities
├── config/               # Configuration management
└── docs/                 # Documentation
    └── architecture/     # Architecture documentation

Implemented Patterns

1. Service-per-Bounded-Context - Separate services for User and Order domains
2. API Style & Versioning - RESTful APIs with versioning
3. Service Discovery & Naming - Configuration-based service discovery
4. API Gateway (Edge) - Centralized API gateway
5. Backends-for-Frontends (BFF) - Web BFF for frontend integration
6. Async Messaging Basics - NATS-based messaging system
7. Idempotent Endpoints & Dedup - Idempotency patterns
8. Data Ownership (Private Schema) - Database per service
9. Outbox Pattern (Transactional Events) - Consistent event publishing
10. Change Data Capture (CDC) for Integration - Event-driven integration
11. Event Schema Governance - Versioned event schemas
12. Consumer-Driven Contracts (CDCt) Testing - Contract testing
13. Anti-Corruption Layer (ACL) - Data transformation layers
14. Read Models & CQRS-Lite - Read/write model separation
15. Caching Tiers (Service & Shared) - Multi-level caching
16. Rate Limits, Quotas, and Shaping - Rate limiting middleware
17. Security: mTLS + AuthN/Z Between Services - JWT-based security
18. Secrets & Config Management (Per Service) - Environment-based config
19. Health, Readiness, and Graceful Shutdown - Health check endpoints
20. Observability: Tracing, Metrics, Correlation - OpenTelemetry integration
21. CI/CD Per Service (Pipelines & Templates) - Workspace-based builds
22. Deployment Topology (Single Region, Many Services) - Kubernetes-ready

Technologies Used

• Rust - Core language
• Axum - Web framework
• SQLx - Database toolkit
• NATS - Messaging system
• OpenTelemetry - Observability
• Tower/Tokio - Async runtime and middleware
• Serde - Serialization
• Moka - Caching

Getting Started

1. Install Rust toolchain
2. Navigate to the project root
3. Run services individually or use workspace commands:

# Build all services
cargo build

# Run a specific service
cargo run -p user-service

# Run the gateway
cargo run -p gateway

Services

• Gateway - Runs on port 3000
• User Service - Runs on port 3001
• Order Service - Runs on port 3002
• Web BFF - Runs on port 3003

Documentation

See docs/architecture/l2-patterns.md for detailed implementation of each pattern.