Как сравнить RestClient и Feign Client? Что лучше выбрать?

RestClient and Feign Client are both used for calling REST services in Java, but they have different approaches and capabilities.

• RestClient (for example, RestTemplate or WebClient in Spring) is a low-level HTTP client that requires manual construction of requests, handling responses, and errors. It is flexible and versatile, suitable for complex scenarios where fine-tuning is needed.

• Feign Client is a declarative HTTP client that allows describing REST APIs as interfaces with annotations. Feign automatically generates implementations, simplifying code and improving readability. It integrates well with Spring Cloud and supports pluggable decoders, error handling, and load balancing.

Which one to choose?

• If you need a simple, declarative, and convenient way to describe REST clients with minimal code — Feign.
• If you require fine control over HTTP requests, customization, or asynchronous operations — RestClient (especially WebClient) is preferable.

Example of Feign:

@FeignClient(name = "userClient", url = "https://api.example.com")
public interface UserClient {
    @GetMapping("/users/{id}")
    User getUserById(@PathVariable("id") Long id);
}

Example of RestTemplate:

RestTemplate restTemplate = new RestTemplate();
User user = restTemplate.getForObject("https://api.example.com/users/{id}", User.class, id);

Ultimately, the choice depends on the project requirements and team preferences.