How are services connected to each other? What interaction approaches have you used?

Services can be interconnected through various interaction mechanisms, depending on the system architecture and requirements. Main approaches:

• Synchronous interaction via HTTP/REST API — services exchange requests and responses in real-time. A simple and common method, but it can lead to delays and resilience issues.

• Asynchronous interaction via message queues (RabbitMQ, Kafka) — services publish events or messages, which other services process independently. Enhances scalability and resilience.

• gRPC or other binary protocols — effective for internal communication between services with low latency.

• Event-driven architecture — services respond to events, simplifying expansion and integration.

• Shared Database — a rare and undesirable approach where multiple services work directly with a single database.

The choice of approach depends on performance, reliability, scalability, and system complexity requirements.