Declarative RestClient is implemented

src/main/java/com/mb/livedataservice/client/jsonplaceholder/DeclarativeJSONPlaceholderRestClient.java

@@ -0,0 +1,26 @@
+package com.mb.livedataservice.client.jsonplaceholder;
+
+import com.mb.livedataservice.client.jsonplaceholder.request.PostRequest;
+import com.mb.livedataservice.client.jsonplaceholder.response.PostResponse;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.service.annotation.DeleteExchange;
+import org.springframework.web.service.annotation.GetExchange;
+import org.springframework.web.service.annotation.PostExchange;
+
+import java.util.List;
+
+public interface DeclarativeJSONPlaceholderRestClient {
+
+    @GetExchange("/posts")
+    List<PostResponse> getAllPosts();
+
+    @GetExchange("/posts/{id}")
+    PostResponse getPost(@PathVariable Integer id);
+
+    @DeleteExchange("/posts/{id}")
+    void deletePost(@PathVariable Integer id);
+
+    @PostExchange("/posts")
+    PostResponse createPost(@RequestBody PostRequest post);
+}

src/main/java/com/mb/livedataservice/config/DeclarativeHttpInterfaces.java

@@ -0,0 +1,54 @@
+package com.mb.livedataservice.config;
+
+import com.mb.livedataservice.client.jsonplaceholder.DeclarativeJSONPlaceholderRestClient;
+import com.mb.livedataservice.exception.BaseException;
+import com.mb.livedataservice.exception.ErrorCode;
+import lombok.SneakyThrows;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.HttpStatusCode;
+import org.springframework.http.client.JdkClientHttpRequestFactory;
+import org.springframework.http.client.support.BasicAuthenticationInterceptor;
+import org.springframework.web.client.RestClient;
+import org.springframework.web.client.support.RestClientAdapter;
+import org.springframework.web.service.invoker.HttpServiceProxyFactory;
+
+import java.time.Duration;
+
+@Configuration
+public class DeclarativeHttpInterfaces {
+
+    @Bean
+    public DeclarativeJSONPlaceholderRestClient declarativeJSONPlaceholderRestClient(RestClient.Builder builder, JSONPlaceholderClientProperties JSONPlaceholderClientProperties) {
+        JdkClientHttpRequestFactory jdkClientHttpRequestFactory = new JdkClientHttpRequestFactory();
+        jdkClientHttpRequestFactory.setReadTimeout(Duration.ofSeconds(15));
+
+        RestClient restClient = builder
+                .baseUrl(JSONPlaceholderClientProperties.getUrl())
+                .requestFactory(jdkClientHttpRequestFactory)
+                .requestInterceptor(new BasicAuthenticationInterceptor(JSONPlaceholderClientProperties.getClientId(), JSONPlaceholderClientProperties.getClientSecret()))
+                .defaultStatusHandler(HttpStatusCode::isError, (request, response) -> {
+                    throw new BaseException(new ErrorCode() {
+
+                        @Override
+                        @SneakyThrows
+                        public HttpStatus getHttpStatus() {
+                            return HttpStatus.resolve(response.getStatusCode().value());
+                        }
+
+                        @Override
+                        @SneakyThrows
+                        public String getCode() {
+                            return response.getStatusText();
+                        }
+                    });
+                })
+                .build();
+
+        return HttpServiceProxyFactory
+                .builderFor(RestClientAdapter.create(restClient))
+                .build()
+                .createClient(DeclarativeJSONPlaceholderRestClient.class);
+    }
+}

src/test/java/com/mb/livedataservice/integration_tests/api/controller/TutorialControllerTest.java

@@ -4,6 +4,7 @@
 import com.mb.livedataservice.api.request.ApiTutorialUpdateRequest;
 import com.mb.livedataservice.api.response.ApiTutorialResponse;
 import com.mb.livedataservice.base.BaseUnitTest;
+import com.mb.livedataservice.client.jsonplaceholder.DeclarativeJSONPlaceholderRestClient;
 import com.mb.livedataservice.client.jsonplaceholder.JSONPlaceholderRestClient;
 import com.mb.livedataservice.client.jsonplaceholder.request.PostRequest;
 import com.mb.livedataservice.client.jsonplaceholder.response.PostResponse;
@@ -66,6 +67,9 @@ class TutorialControllerTest extends BaseUnitTest {
     @Autowired
     private JSONPlaceholderRestClient JSONPlaceholderRestClient;
 
+    @Autowired
+    private DeclarativeJSONPlaceholderRestClient declarativeJSONPlaceholderRestClient;
+
     @BeforeAll
     static void setup(@Autowired TestRestTemplate restTemplate) {
         //Prepare some test data
@@ -215,4 +219,28 @@ void shouldGetPostById() {
         PostResponse post = JSONPlaceholderRestClient.getPostById(5);
         assertNotNull(post);
     }
+
+    @Test
+    public void shouldGetAllPosts() {
+        List<PostResponse> posts = declarativeJSONPlaceholderRestClient.getAllPosts();
+        assertThat(posts.size()).isEqualTo(100);
+    }
+
+    @Test
+    public void shouldGetSinglePost() {
+        PostResponse post = declarativeJSONPlaceholderRestClient.getPost(5);
+        assertThat(post.id()).isEqualTo(5);
+    }
+
+    @Test
+    public void shouldDeleteSinglePost() {
+        declarativeJSONPlaceholderRestClient.deletePost(5);
+    }
+
+    @Test
+    public void shouldCreateNewPost() {
+        PostRequest newPost = new PostRequest(1, null, "new title", "new body");
+        PostResponse post = declarativeJSONPlaceholderRestClient.createPost(newPost);
+        assertThat("new title").isEqualTo(post.title());
+    }
 }