Spring Boot 3.2+ ile Java veya Kotlin arayüzleri üzerinden deklaratif ve tip güvenli HTTP istemcileri tanımlayabilirsiniz. Bu makalede JSONPlaceholder API örneği ile baştan sona nasıl yapılandıracağınızı öğreneceksiniz.
Spring Boot 3.2+ ile Java veya Kotlin arayüzleri üzerinden deklaratif ve tip güvenli HTTP istemcileri tanımlayabilirsiniz. Bu makalede JSONPlaceholder API örneği ile baştan sona nasıl yapılandıracağınızı öğreneceksiniz.
Bu bölümde Neden HTTP Arayüz İstemcisi? konusunu netleştirip uygulamada kullanacağınız temel noktaları özetliyoruz.
@HttpExchange, @GetExchange ve WebClientAdapter bileşenlerini kullanır.Bu bölümde Gereksinimler konusunu netleştirip uygulamada kullanacağınız temel noktaları özetliyoruz.
Projenizin yapı dosyasına Web starter’ı ekleyin:
Maven:
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency>
Gradle:
implementation 'org.springframework.boot:spring-boot-starter-web'
application.yml veya application.properties dosyanıza ekleyin:
jsonplaceholder: base-url: https://jsonplaceholder.typicode.com
jsonplaceholder.base-url=https://jsonplaceholder.typicode.com
./mvnw spring-boot:run # veya gradle bootRun
curl http://localhost:8080/posts curl http://localhost:8080/posts/1
Artık Spring Boot HTTP Interface Client için üretim odaklı bir Spring Boot temeliniz var. Sonraki adımda ayarları kendi domainine uyarlayıp test ve gözlemlenebilirlik katmanını ekleyerek gerçek trafik altında doğrulayın.
// src/main/java/com/example/client/dto/PostDTO.java package com.example.client.dto; public record PostDTO( Integer userId, Integer id, String title, String body ) {} // src/main/java/com/example/client/JsonPlaceholderClient.java package com.example.client; import com.example.client.dto.PostDTO; import org.springframework.web.service.annotation.GetExchange; import org.springframework.web.service.annotation.HttpExchange; import org.springframework.web.bind.annotation.PathVariable; import java.util.List; @HttpExchange(url = "${jsonplaceholder.base-url}", accept = "application/json") public interface JsonPlaceholderClient { @GetExchange("/posts") List<PostDTO> getPosts(); @GetExchange("/posts/{id}") PostDTO getPost(@PathVariable("id") Integer id); }
// src/main/kotlin/com/example/client/dto/PostDTO.kt package com.example.client.dto data class PostDTO( val userId: Int, val id: Int, val title: String, val body: String ) // src/main/kotlin/com/example/client/JsonPlaceholderClient.kt package com.example.client import com.example.client.dto.PostDTO import org.springframework.web.service.annotation.GetExchange import org.springframework.web.service.annotation.HttpExchange import org.springframework.web.bind.annotation.PathVariable @HttpExchange(url = "${jsonplaceholder.base-url}", accept = "application/json") interface JsonPlaceholderClient { @GetExchange("/posts") fun getPosts(): List<PostDTO> @GetExchange("/posts/{id}") fun getPost(@PathVariable("id") id: Int): PostDTO }
// src/main/java/com/example/config/HttpClientConfig.java package com.example.config; import com.example.client.JsonPlaceholderClient; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.web.client.support.RestClientAdapter; import org.springframework.web.service.invoker.HttpServiceProxyFactory; import org.springframework.web.service.invoker.RestClient; @Configuration public class HttpClientConfig { @Bean public JsonPlaceholderClient jsonPlaceholderClient(RestClient.Builder restClientBuilder) { RestClient restClient = restClientBuilder .baseUrl("https://jsonplaceholder.typicode.com") .build(); var factory = HttpServiceProxyFactory .builderFor(RestClientAdapter.create(restClient)) .build(); return factory.createClient(JsonPlaceholderClient.class); } }
// src/main/kotlin/com/example/config/HttpClientConfig.kt package com.example.config import com.example.client.JsonPlaceholderClient import org.springframework.context.annotation.Bean import org.springframework.context.annotation.Configuration import org.springframework.web.client.support.RestClientAdapter import org.springframework.web.service.invoker.HttpServiceProxyFactory import org.springframework.web.service.invoker.RestClient @Configuration class HttpClientConfig { @Bean fun jsonPlaceholderClient(restClientBuilder: RestClient.Builder): JsonPlaceholderClient { val restClient = restClientBuilder .baseUrl("https://jsonplaceholder.typicode.com") .build() val factory = HttpServiceProxyFactory .builderFor(RestClientAdapter.create(restClient)) .build() return factory.createClient(JsonPlaceholderClient::class.java) } }
// src/main/java/com/example/service/PostService.java package com.example.service; import com.example.client.JsonPlaceholderClient; import com.example.client.dto.PostDTO; import lombok.RequiredArgsConstructor; import org.springframework.stereotype.Service; import java.util.List; @Service @RequiredArgsConstructor public class PostService { private final JsonPlaceholderClient client; public List<PostDTO> getAllPosts() { return client.getPosts(); } public PostDTO getPostById(Integer id) { return client.getPost(id); } } // src/main/java/com/example/controller/PostController.java package com.example.controller; import com.example.client.dto.PostDTO; import com.example.service.PostService; import lombok.RequiredArgsConstructor; import org.springframework.http.ResponseEntity; import org.springframework.web.bind.annotation.*; import java.util.List; @RestController @RequestMapping("/posts") @RequiredArgsConstructor public class PostController { private final PostService postService; @GetMapping public List<PostDTO> getAllPosts() { return postService.getAllPosts(); } @GetMapping("/{id}") public ResponseEntity<PostDTO> getPostById(@PathVariable Integer id) { PostDTO post = postService.getPostById(id); return post != null ? ResponseEntity.ok(post) : ResponseEntity.notFound().build(); } }
// src/main/kotlin/com/example/service/PostService.kt package com.example.service import com.example.client.JsonPlaceholderClient import com.example.client.dto.PostDTO import org.springframework.stereotype.Service @Service class PostService(private val client: JsonPlaceholderClient) { fun getAllPosts(): List<PostDTO> = client.getPosts() fun getPostById(id: Int): PostDTO = client.getPost(id) } // src/main/kotlin/com/example/controller/PostController.kt package com.example.controller import com.example.client.dto.PostDTO import com.example.service.PostService import org.springframework.http.ResponseEntity import org.springframework.web.bind.annotation.* @RestController @RequestMapping("/posts") class PostController(private val postService: PostService) { @GetMapping fun getAllPosts(): List<PostDTO> = postService.getAllPosts() @GetMapping("/{id}") fun getPostById(@PathVariable id: Int): ResponseEntity<PostDTO> = ResponseEntity.ok(postService.getPostById(id)) }