The Circuit Breaker pattern is a critical Java design pattern that helps ensure fault tolerance and resilience in microservices and distributed systems. Using Circuit Breaker, it is possible to prevent a system from repeatedly trying to execute an operation likely to fail, allowing it to recover from faults and prevent cascading failures.
The intent of the Commander pattern in Java, especially in the context of distributed transactions, is to manage and coordinate complex transactions across multiple distributed components or services. This pattern ensures data consistency and integrity in distributed systems, making it crucial for microservices architecture. It encapsulates transaction commands and coordination logic, facilitating the implementation of distributed transaction protocols like two-phase commit or Saga.
The Health Check pattern in Java is designed to proactively monitor the health of individual software components or services, allowing for quick identification and remediation of issues that may affect overall system functionality in microservices architectures.
The Microservices Aggregator pattern helps aggregate responses from multiple microservices into a single unified response, optimizing client-server interactions in scalable systems.
The API Gateway design pattern aims to provide a unified interface to a set of microservices within a microservices architecture. It acts as a single entry point for clients, routing requests to the appropriate microservices and aggregating results, thereby simplifying the client-side code.
Log Aggregation is a crucial microservices design pattern that centralizes the collection, storage, and analysis of logs from multiple sources, facilitating efficient monitoring, debugging, and operational intelligence.
To manage and coordinate distributed transactions across multiple services in a fault-tolerant and reliable manner.
Real-world example
Imagine a travel agency coordinating a vacation package for a customer. The package includes booking a flight, reserving a hotel room, and renting a car. Each of these bookings is managed by a different service provider. If the flight booking is successful but the hotel is fully booked, the agency needs to cancel the flight and notify the customer. This ensures that the customer does not end up with only a partial vacation package. In the Saga pattern, this scenario is managed by a series of coordinated transactions, with compensating actions (like canceling the flight) to maintain consistency.
