Microservices Patterns
Microservices Patterns
Comprehensive guide to microservices patterns and anti-patterns
Decompose by Business Capability
Organize services around business capabilities rather than technical layers
Use Case:
When you need to align services with business domains and reduce coupling
Pros:
- +Services aligned with business functions
- +Teams can work independently
- +Clear service boundaries
Cons:
- -Requires deep business domain knowledge
- -May result in data duplication
- -Complex cross-service transactions
Examples:
Decompose by Subdomain
Use Domain-Driven Design subdomains to define service boundaries
Use Case:
When applying DDD principles to microservices architecture
Pros:
- +Clear domain boundaries
- +Reduced coupling between services
- +Better team autonomy
Cons:
- -Requires DDD expertise
- -Complex domain modeling
- -Potential service proliferation
Examples:
Database per Service
Each microservice has its own private database
Use Case:
When you need data isolation and service autonomy
Pros:
- +Service independence
- +Technology diversity
- +Better fault isolation
Cons:
- -Data consistency challenges
- -Complex queries across services
- -Increased operational overhead
Examples:
Shared Database
Multiple services sharing the same database
Use Case:
Never recommended - included as anti-pattern example
Pros:
- +Simple ACID transactions
- +Easy data consistency
- +Familiar development model
Cons:
- -Tight coupling between services
- -Difficult to scale independently
- -Technology lock-in
Examples:
Saga Pattern
Manage distributed transactions using a sequence of local transactions
Use Case:
When you need to maintain data consistency across multiple services
Pros:
- +Maintains data consistency
- +Better fault tolerance
- +No distributed locks
Cons:
- -Complex error handling
- -Eventual consistency
- -Difficult debugging
Examples:
API Gateway
Single entry point for all client requests to microservices
Use Case:
When you need to manage cross-cutting concerns and client complexity
Pros:
- +Single entry point
- +Cross-cutting concerns handling
- +Request routing and composition
Cons:
- -Single point of failure
- -Performance bottleneck
- -Additional complexity
Examples:
Backend for Frontend (BFF)
Create separate backend services for different frontend applications
Use Case:
When different clients have different data and API requirements
Pros:
- +Optimized for specific clients
- +Reduced client complexity
- +Independent evolution
Cons:
- -Code duplication
- -Additional services to maintain
- -Potential inconsistencies
Examples:
Service Mesh
Infrastructure layer for service-to-service communication
Use Case:
When you need advanced traffic management and observability
Pros:
- +Traffic management
- +Security policies
- +Observability
Cons:
- -Additional complexity
- -Performance overhead
- -Learning curve
Examples:
Circuit Breaker
Prevent cascading failures by monitoring service health
Use Case:
When you need to handle service failures gracefully
Pros:
- +Prevents cascading failures
- +Fast failure detection
- +Automatic recovery
Cons:
- -Additional complexity
- -Configuration overhead
- -Potential false positives
Examples:
Bulkhead
Isolate resources to prevent total system failure
Use Case:
When you need to isolate critical resources from failures
Pros:
- +Fault isolation
- +Resource protection
- +Better availability
Cons:
- -Resource overhead
- -Complex configuration
- -Potential underutilization
Examples:
Distributed Tracing
Track requests across multiple services
Use Case:
When you need to debug and monitor distributed systems
Pros:
- +End-to-end visibility
- +Performance analysis
- +Debugging capabilities
Cons:
- -Performance overhead
- -Storage requirements
- -Complex setup
Examples:
Health Check API
Provide endpoints for monitoring service health
Use Case:
When you need to monitor service availability and health
Pros:
- +Service health visibility
- +Automated monitoring
- +Load balancer integration
Cons:
- -Additional endpoints to maintain
- -Potential security exposure
- -False positive/negative risks
Examples:
Distributed Monolith
Microservices that are tightly coupled and must be deployed together
Use Case:
Anti-pattern to avoid - services should be independently deployable
Pros:
- +None - this is an anti-pattern
Cons:
- -Tight coupling
- -Deployment dependencies
- -Reduced benefits of microservices
Examples:
Chatty Interfaces
Services making too many fine-grained calls to each other
Use Case:
Anti-pattern to avoid - design coarse-grained interfaces
Pros:
- +None - this is an anti-pattern
Cons:
- -Poor performance
- -Network overhead
- -Increased latency
Examples:
Pattern Categories Summary
Pro Tip: Start with decomposition patterns to define service boundaries, then apply communication and data management patterns. Always be aware of anti-patterns to avoid common pitfalls in microservices architecture.