.NET Architecture & System Design Interview Question #115

When should you use REST between services?

Microservices, API Gateway, Service Communication & Event-Driven Architecture Mid-Level Intermediate

Quick Interview Answer

REST over HTTP is appropriate when services need request-response communication, broad interoperability, resource-oriented APIs, and standard web infrastructure.

Detailed Explanation

REST over HTTP is appropriate when services need request-response communication, broad interoperability, resource-oriented APIs, and standard web infrastructure.

For internal service calls, REST is easy to inspect and widely supported. However, excessive synchronous REST chains can create latency and availability coupling, so not every interaction should be a direct HTTP call.

Code Example

GET /api/orders/42
POST /api/orders

Service A
   |
 HTTP/JSON
   v
Service B