Can you give examples of architectural patterns used in microservices development?

Microservice systems often employ the following architectural patterns:

• API Gateway: a single entry point for all clients that routes requests to the appropriate microservices, performs authentication, data aggregation, and caching.

• Circuit Breaker: a pattern to increase system resilience, preventing repeated calls to a failing service, allowing the system to recover quickly.

• Event-Driven Architecture: microservices interact through events, ensuring loose coupling and asynchronous communication.

• Database per Service: each microservice has its own database, which helps avoid conflicts and increases independence.

• Service Discovery: automatic detection of microservice addresses in a dynamic environment.

• Saga Pattern: managing distributed transactions through a sequence of local transactions with compensating actions.

An example of using Circuit Breaker in Python with the pybreaker library:

import pybreaker

circuit_breaker = pybreaker.CircuitBreaker(fail_max=3, reset_timeout=60)

@circuit_breaker
def call_microservice():
    # call to an external microservice
    pass

These patterns help build scalable, resilient, and easily maintainable microservice systems.