Enterprise integration patterns
I implement well-established integration patterns for reliable, scalable architectures:
Event-driven architecture
Event sourcing pattern
Store application state as a sequence of events. Benefits include:
- Complete audit trail of all state changes
- Ability to rebuild state by replaying events
- Temporal queries (view state at any point in time)
- Support for event-driven microservices
Implementation: Event Hubs for ingestion, Event Grid for routing, Cosmos DB for event store
CQRS (command query responsibility segregation)
Separate read and write operations for optimized performance:
- Write model optimized for consistency and validation
- Read models denormalized for query performance
- Independent scaling of read and write workloads
- Different data stores for commands and queries
Implementation: Service Bus for commands, Event Grid for synchronization, SQL/Cosmos for read models
Saga pattern for distributed transactions
Manage long-running business processes across multiple services:
- Choreography: Services publish events and react to events from others
- Orchestration: Central coordinator manages saga execution
- Compensation: Undo completed steps if saga fails
- Eventual consistency across distributed systems
Implementation: Durable Functions for orchestration, Service Bus for reliable messaging
A saga in action
When one step of a multi-system process fails, the steps that already completed are undone in reverse order, so no system is left half-updated.
An order saga with compensation
Create order
Order API
Reserve stock
Inventory
Charge payment
Payments
Book shipment
Carrier
Messaging patterns
- Request-reply: Synchronous communication with response correlation
- Publish-subscribe: One-to-many message distribution with topics
- Competing consumers: Multiple workers processing messages from a queue
- Message routing: Content-based routing with filters and subscriptions
- Priority queue: Process high-priority messages first
- Claim check: Store large payloads externally, pass reference in message