BAEL-1756 (#4230)

* code samples for spring data key value
BAEL-1467

* changes to add spring-data-keyvalue to parent pom.

* Update README.md

* Update README.md

* Update README.md

* How to Use Spring RestTemplate Interceptor

* Spring annotations article (#4232)

* Spring annotations

* commented VehicleFactoryApplication to fix CI build

* BAEL-1756 Test typo fixed

spring-rest/src/main/java/com/baeldung/transfer/LoginForm.java

@@ -7,6 +7,12 @@ public class LoginForm {
     public LoginForm() {
     }
 
+    public LoginForm(String username, String password) {
+        super();
+        this.username = username;
+        this.password = password;
+    }
+    
     public String getUsername() {
         return username;
     }

spring-rest/src/main/java/org/baeldung/config/RestClientConfig.java

@@ -0,0 +1,30 @@
+package org.baeldung.config;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.baeldung.interceptors.RestTemplateLoggingInterceptor;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.client.BufferingClientHttpRequestFactory;
+import org.springframework.http.client.ClientHttpRequestInterceptor;
+import org.springframework.http.client.SimpleClientHttpRequestFactory;
+import org.springframework.util.CollectionUtils;
+import org.springframework.web.client.RestTemplate;
+
+@Configuration
+public class RestClientConfig {
+
+    @Bean
+    public RestTemplate restTemplate() {
+        RestTemplate restTemplate = new RestTemplate(new BufferingClientHttpRequestFactory(new SimpleClientHttpRequestFactory()));
+
+        List<ClientHttpRequestInterceptor> interceptors = restTemplate.getInterceptors();
+        if (CollectionUtils.isEmpty(interceptors)) {
+            interceptors = new ArrayList<ClientHttpRequestInterceptor>();
+        }
+        interceptors.add(new RestTemplateLoggingInterceptor());
+        restTemplate.setInterceptors(interceptors);
+        return restTemplate;
+    }
+}

spring-rest/src/main/java/org/baeldung/interceptors/RestTemplateLoggingInterceptor.java

@@ -0,0 +1,41 @@
+package org.baeldung.interceptors;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+
+import org.apache.commons.lang3.StringUtils;
+import org.springframework.http.HttpRequest;
+import org.springframework.http.client.ClientHttpRequestExecution;
+import org.springframework.http.client.ClientHttpRequestInterceptor;
+import org.springframework.http.client.ClientHttpResponse;
+import org.springframework.util.StreamUtils;
+
+public class RestTemplateLoggingInterceptor implements ClientHttpRequestInterceptor {
+
+    @Override
+    public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
+        logRequest(body);
+        ClientHttpResponse response = execution.execute(request, body);
+        logResponse(response);
+        response.getHeaders().add("Foo", "bar");
+        return response;
+    }
+
+    private void logRequest(byte[] body) {
+        String payLoad = StringUtils.EMPTY;
+        if (body.length > 0) {
+            payLoad = new String(body, StandardCharsets.UTF_8);
+        }
+        System.out.println("Request Body > " + payLoad);
+    }
+
+    private void logResponse(ClientHttpResponse response) throws IOException {
+        String payLoad = StringUtils.EMPTY;
+        long contentLength = response.getHeaders()
+            .getContentLength();
+        if (contentLength != 0) {
+            payLoad = StreamUtils.copyToString(response.getBody(), StandardCharsets.UTF_8);
+        }
+        System.out.println("Response Body > " + payLoad);
+    }
+}

spring-rest/src/test/java/org/baeldung/resttemplate/RestTemplateIntegrationTest.java

@@ -0,0 +1,43 @@
+package org.baeldung.resttemplate;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+import org.baeldung.config.RestClientConfig;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.web.client.RestTemplate;
+
+import com.baeldung.transfer.LoginForm;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes = RestClientConfig.class)
+public class RestTemplateIntegrationTest {
+
+    @Autowired
+    RestTemplate restTemplate;
+
+    @Test
+    public void givenRestTemplate_whenRequested_thenLogAndModifyResponse() {
+        LoginForm loginForm = new LoginForm("userName", "password");
+        HttpHeaders headers = new HttpHeaders();
+        headers.setContentType(MediaType.APPLICATION_JSON);
+        HttpEntity<LoginForm> requestEntity = new HttpEntity<LoginForm>(loginForm, headers);
+
+        ResponseEntity<String> responseEntity = restTemplate.postForEntity("http://httpbin.org/post", requestEntity, String.class);
+
+        assertThat(responseEntity.getStatusCode(), is(equalTo(HttpStatus.OK)));
+        assertThat(responseEntity.getHeaders()
+            .get("Foo")
+            .get(0), is(equalTo("bar")));
+    }
+}