How is communication between microservices implemented in the system architecture?

In microservices architecture, communication between services is usually implemented through:

• HTTP REST API — the most common method, where microservices exchange data via HTTP requests using JSON or another format.
• gRPC — a high-performance remote procedure call protocol, often used in Go for efficient communication.
• Messages through message brokers (e.g., RabbitMQ, Kafka) — asynchronous message exchange, allowing services to be loosely coupled and scalable.

Example of a simple HTTP client in Go to call another microservice:

resp, err := http.Get("http://serviceB/api/data")
if err != nil {
    log.Fatal(err)
}
defer resp.Body.Close()
body, _ := ioutil.ReadAll(resp.Body)
fmt.Println(string(body))

The choice of method depends on performance requirements, reliability, and architectural decisions.