Microservice pattern: Command-side replica

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Description:
The Command-Side Replica design pattern in a microservices architecture focuses on creating replicas of the command side of the services to handle command requests more efficiently. This pattern is beneficial in scenarios where the command operations need to be highly available and scalable. By implementing command-side replicas, we ensure that the system can handle high loads and maintain performance and reliability.

Main elements of the pattern:

1. Command Replication: Creating multiple instances of the command service to distribute the load.
2. Load Balancing: Utilizing load balancers to distribute incoming command requests across the replicas.
3. Consistency Management: Ensuring that all replicas remain consistent, often using techniques like eventual consistency or distributed transactions.
4. Fault Tolerance: Implementing mechanisms to handle failures and ensure high availability of command services.

References:

1. Microservices Patterns: With examples in Java
2. Designing Data-Intensive Applications
3. Command-Side Replica Pattern
4. Project Contribution Guidelines

Acceptance Criteria:

1. A working implementation of the Command-Side Replica pattern with at least two replicas handling command requests.
2. Proper load balancing setup to distribute incoming requests across the replicas.
3. Documentation and unit tests demonstrating the functionality, consistency, and fault tolerance of the implemented pattern.