Could you describe the main principles and structure of microservices architecture?

Microservices architecture is a style of building applications where the system is broken down into many small, independent services, each responsible for its own business function.

Main principles:

• Modularity and independence: each microservice implements a specific functionality and can be developed, deployed, and scaled independently.
• Data isolation: each service manages its own database, reducing coupling.
• Communication via API: interaction between services occurs through well-defined interfaces, most often REST or gRPC.
• Autonomy: services can be written in different languages and use different technologies.
• Fault tolerance: failure of one service should not lead to the collapse of the entire system.

The structure of a microservices architecture typically includes:

• A set of microservices, each responsible for a specific business logic.
• API Gateway — an entry point for clients that routes requests to the appropriate services.
• Message exchange systems or brokers (e.g., Kafka, RabbitMQ) for asynchronous interaction.
• Monitoring and logging systems to track the state of services.

Example of a microservice in C# (Web API):

[ApiController]
[Route("api/[controller]")]
public class OrdersController : ControllerBase
{
    [HttpGet("{id}")]
    public IActionResult GetOrder(int id)
    {
        // Logic to get the order
        return Ok(new { Id = id, Product = "Book", Quantity = 1 });
    }
}