DATAREST-573 - Polishing.

Removed RepositoryRestConfiguration.addCorsMapping(…) as we currently don't have any other shortcut methods for configuration like this.

Tweaked the setup of (now Repository)CorsConfigurationAccessor to be created earlier so that we avoid recreation for every lookup. Introduced a NoOpStringValueResolver to be used by default so that we don't need to deal with the case of the resolver being null at the end of the call chain. Replaced constructor of RepositoryCorsConfigurationAccessor with corresponding Lombok annotation.

Updated reference documentation accordingly.

Original pull request: spring-projects#233.

Author: odrotbohm

spring-data-rest-core/src/main/java/org/springframework/data/rest/core/config/RepositoryRestConfiguration.java

@@ -28,7 +28,6 @@
 import org.springframework.http.MediaType;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
-import org.springframework.web.cors.CorsConfiguration;
 import org.springframework.web.servlet.config.annotation.CorsRegistration;
 
 /**
@@ -565,22 +564,6 @@ public RepositoryCorsRegistry getCorsRegistry() {
 		return corsRegistry;
 	}
 
-	/**
-	 * Configures Cross-origin resource sharing given a {@code path}.
-	 *
-	 * @param path path or path pattern, must not be {@literal null} or empty.
-	 * @return the {@link CorsRegistration} to build a CORS configuration.
-	 * @since 2.6
-	 * @see CorsConfiguration
-	 */
-	public CorsRegistration addCorsMapping(String path) {
-
-		Assert.notNull(path, "Path must not be null!");
-		Assert.hasText(path, "Path must not be empty!");
-
-		return corsRegistry.addMapping(path);
-	}
-
 	/**
 	 * Returns the {@link EntityLookupRegistrar} to create custom {@link EntityLookup} instances registered in the
 	 * configuration.

spring-data-rest-core/src/test/java/org/springframework/data/rest/core/RepositoryRestConfigurationUnitTests.java

@@ -26,6 +26,7 @@
 import org.springframework.data.rest.core.config.EnumTranslationConfiguration;
 import org.springframework.data.rest.core.config.MetadataConfiguration;
 import org.springframework.data.rest.core.config.ProjectionDefinitionConfiguration;
+import org.springframework.data.rest.core.config.RepositoryCorsRegistry;
 import org.springframework.data.rest.core.config.RepositoryRestConfiguration;
 import org.springframework.data.rest.core.domain.Profile;
 import org.springframework.data.rest.core.domain.ProfileRepository;
@@ -149,9 +150,10 @@ public void considersDomainTypeOfValueRepositoryLookupTypes() {
 	@Test
 	public void configuresCorsProcessing() {
 
-		configuration.addCorsMapping("/hello").maxAge(1234);
+		RepositoryCorsRegistry registry = configuration.getCorsRegistry();
+		registry.addMapping("/hello").maxAge(1234);
 
-		Map<String, CorsConfiguration> corsConfigurations = configuration.getCorsRegistry().getCorsConfigurations();
+		Map<String, CorsConfiguration> corsConfigurations = registry.getCorsConfigurations();
 		assertThat(corsConfigurations, hasKey("/hello"));
 
 		CorsConfiguration corsConfiguration = corsConfigurations.get("/hello");

spring-data-rest-tests/spring-data-rest-tests-jpa/src/main/java/org/springframework/data/rest/webmvc/jpa/AuthorRepository.java

@@ -15,14 +15,17 @@
  */
 package org.springframework.data.rest.webmvc.jpa;
 
+import static org.springframework.web.bind.annotation.RequestMethod.*;
+
 import org.springframework.data.repository.CrudRepository;
 import org.springframework.web.bind.annotation.CrossOrigin;
-import org.springframework.web.bind.annotation.RequestMethod;
 
 /**
  * @author Oliver Gierke
  * @author Mark Paluch
  */
-@CrossOrigin(origins = "http://not.so.far.away", allowCredentials = "true",
-		methods = { RequestMethod.GET, RequestMethod.PATCH }, maxAge = 1234)
+@CrossOrigin(origins = "http://not.so.far.away", //
+		allowCredentials = "true", //
+		methods = { GET, PATCH }, //
+		maxAge = 1234)
 public interface AuthorRepository extends CrudRepository<Author, Long> {}

spring-data-rest-tests/spring-data-rest-tests-jpa/src/test/java/org/springframework/data/rest/webmvc/jpa/CorsIntegrationTests.java

@@ -15,11 +15,9 @@
  */
 package org.springframework.data.rest.webmvc.jpa;
 
-import static org.hamcrest.Matchers.containsString;
-import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
-import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.options;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.header;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+import static org.hamcrest.Matchers.*;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
 
 import org.junit.Test;
 import org.springframework.context.annotation.Bean;
@@ -58,7 +56,7 @@ RepositoryRestConfigurer repositoryRestConfigurer() {
 				@Override
 				public void configureRepositoryRestConfiguration(RepositoryRestConfiguration config) {
 
-					config.addCorsMapping("/books/**") //
+					config.getCorsRegistry().addMapping("/books/**") //
 							.allowedMethods("GET", "PUT", "POST") //
 							.allowedOrigins("http://far.far.away");
 				}
@@ -79,7 +77,8 @@ public void appliesSelectiveDefaultCorsConfiguration() throws Exception {
 				.header(HttpHeaders.ACCESS_CONTROL_REQUEST_METHOD, "POST")) //
 				.andExpect(status().isOk()) //
 				.andExpect(header().string(HttpHeaders.ACCESS_CONTROL_ALLOW_ORIGIN, "http://far.far.away")) //
-				.andExpect(header().string(HttpHeaders.ACCESS_CONTROL_ALLOW_METHODS, "GET,HEAD,POST,PUT,PATCH,DELETE,OPTIONS,TRACE"));
+				.andExpect(
+						header().string(HttpHeaders.ACCESS_CONTROL_ALLOW_METHODS, "GET,HEAD,POST,PUT,PATCH,DELETE,OPTIONS,TRACE"));
 	}
 
 	/**

spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/RepositoryRestHandlerMapping.java

@@ -15,6 +15,9 @@
  */
 package org.springframework.data.rest.webmvc;
 
+import lombok.NonNull;
+import lombok.RequiredArgsConstructor;
+
 import java.util.Arrays;
 import java.util.HashSet;
 import java.util.LinkedHashSet;
@@ -66,7 +69,7 @@ public class RepositoryRestHandlerMapping extends BasePathAwareHandlerMapping {
 	private final RepositoryRestConfiguration configuration;
 	private final Repositories repositories;
 
-	private StringValueResolver embeddedValueResolver;
+	private RepositoryCorsConfigurationAccessor corsConfigurationAccessor;
 	private JpaHelper jpaHelper;
 
 	/**
@@ -99,6 +102,8 @@ public RepositoryRestHandlerMapping(ResourceMappings mappings, RepositoryRestCon
 		this.mappings = mappings;
 		this.configuration = config;
 		this.repositories = repositories;
+		this.corsConfigurationAccessor = new RepositoryCorsConfigurationAccessor(mappings, repositories,
+				NoOpStringValueResolver.INSTANCE);
 	}
 
 	/**
@@ -108,14 +113,17 @@ public void setJpaHelper(JpaHelper jpaHelper) {
 		this.jpaHelper = jpaHelper;
 	}
 
-	/* (non-Javadoc)
+	/*
+	 * (non-Javadoc)
 	 * @see org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping#setEmbeddedValueResolver(org.springframework.util.StringValueResolver)
 	 */
 	@Override
 	public void setEmbeddedValueResolver(StringValueResolver resolver) {
 
-		embeddedValueResolver = resolver;
 		super.setEmbeddedValueResolver(resolver);
+
+		this.corsConfigurationAccessor = new RepositoryCorsConfigurationAccessor(mappings, repositories,
+				resolver == null ? NoOpStringValueResolver.INSTANCE : resolver);
 	}
 
 	/*
@@ -207,15 +215,10 @@ protected CorsConfiguration getCorsConfiguration(Object handler, HttpServletRequ
 			return corsConfiguration;
 		}
 
-		// Repository root resource
-		CorsConfiguration repositoryConfiguration = new CorsConfigurationAccessor(mappings, repositories,
-				embeddedValueResolver).findCorsConfiguration(lookupPath);
-
-		if (repositoryConfiguration != null) {
-			return corsConfiguration != null ? corsConfiguration.combine(repositoryConfiguration) : repositoryConfiguration;
-		}
+		CorsConfiguration repositoryCorsConfiguration = corsConfigurationAccessor.findCorsConfiguration(lookupPath);
 
-		return corsConfiguration;
+		return corsConfiguration == null ? repositoryCorsConfiguration
+				: corsConfiguration.combine(repositoryCorsConfiguration);
 	}
 
 	/**
@@ -231,37 +234,40 @@ private static String getRepositoryBasePath(String repositoryLookupPath) {
 	}
 
 	/**
-	 * Accessor to obtain {@link CorsConfiguration} for exposed repositories.
-	 * <p>
-	 * Exported Repository classes can be annotated with {@link CrossOrigin} to configure CORS for a specific repository.
+	 * No-op {@link StringValueResolver} that returns the given {@link String} value as is.
 	 *
-	 * @author Mark Paluch
+	 * @author Oliver Gierke
 	 * @since 2.6
 	 */
-	static class CorsConfigurationAccessor {
+	enum NoOpStringValueResolver implements StringValueResolver {
 
-		private final ResourceMappings mappings;
-		private final Repositories repositories;
-		private final StringValueResolver embeddedValueResolver;
+		INSTANCE;
 
-		/**
-		 * Creates a new {@link CorsConfigurationAccessor} given {@link ResourceMappings}, {@link Repositories} and
-		 * {@link StringValueResolver}.
-		 *
-		 * @param mappings must not be {@literal null}.
-		 * @param repositories must not be {@literal null}.
-		 * @param embeddedValueResolver may be {@literal null} if not present.
+		/* 
+		 * (non-Javadoc)
+		 * @see org.springframework.util.StringValueResolver#resolveStringValue(java.lang.String)
 		 */
-		CorsConfigurationAccessor(ResourceMappings mappings, Repositories repositories,
-				StringValueResolver embeddedValueResolver) {
+		@Override
+		public String resolveStringValue(String value) {
+			return value;
+		}
+	}
 
-			Assert.notNull(mappings, "ResourceMappings must not be null!");
-			Assert.notNull(repositories, "Repositories must not be null!");
+	/**
+	 * Accessor to obtain {@link CorsConfiguration} for exposed repositories.
+	 * <p>
+	 * Exported repository classes can be annotated with {@link CrossOrigin} to configure CORS for a specific repository.
+	 *
+	 * @author Mark Paluch
+	 * @author Oliver Gierke
+	 * @since 2.6
+	 */
+	@RequiredArgsConstructor
+	static class RepositoryCorsConfigurationAccessor {
 
-			this.mappings = mappings;
-			this.repositories = repositories;
-			this.embeddedValueResolver = embeddedValueResolver;
-		}
+		private final @NonNull ResourceMappings mappings;
+		private final @NonNull Repositories repositories;
+		private final @NonNull StringValueResolver embeddedValueResolver;
 
 		CorsConfiguration findCorsConfiguration(String lookupPath) {
 
@@ -305,7 +311,7 @@ protected CorsConfiguration createConfiguration(Class<?> repositoryInterface) {
 			if (CollectionUtils.isEmpty(config.getAllowedOrigins())) {
 				config.setAllowedOrigins(Arrays.asList(CrossOrigin.DEFAULT_ORIGINS));
 			}
-			
+
 			if (CollectionUtils.isEmpty(config.getAllowedMethods())) {
 				for (HttpMethod httpMethod : HttpMethod.values()) {
 					config.addAllowedMethod(httpMethod);
@@ -362,7 +368,7 @@ private void updateCorsConfig(CorsConfiguration config, CrossOrigin annotation)
 		}
 
 		private String resolveCorsAnnotationValue(String value) {
-			return (this.embeddedValueResolver != null ? this.embeddedValueResolver.resolveStringValue(value) : value);
+			return this.embeddedValueResolver.resolveStringValue(value);
 		}
 	}
 }

…/CorsConfigurationAccessorUnitTests.java …yCorsConfigurationAccessorUnitTests.javaspring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/CorsConfigurationAccessorUnitTests.java renamed to spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/RepositoryCorsConfigurationAccessorUnitTests.java spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/CorsConfigurationAccessorUnitTests.java renamed to spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/RepositoryCorsConfigurationAccessorUnitTests.java

@@ -15,7 +15,7 @@
  */
 package org.springframework.data.rest.webmvc;
 
-import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.MatcherAssert.*;
 import static org.hamcrest.Matchers.*;
 
 import org.junit.Before;
@@ -25,28 +25,31 @@
 import org.mockito.runners.MockitoJUnitRunner;
 import org.springframework.data.repository.support.Repositories;
 import org.springframework.data.rest.core.mapping.ResourceMappings;
-import org.springframework.data.rest.webmvc.RepositoryRestHandlerMapping.CorsConfigurationAccessor;
+import org.springframework.data.rest.webmvc.RepositoryRestHandlerMapping.NoOpStringValueResolver;
+import org.springframework.data.rest.webmvc.RepositoryRestHandlerMapping.RepositoryCorsConfigurationAccessor;
 import org.springframework.web.bind.annotation.CrossOrigin;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.cors.CorsConfiguration;
 
 /**
- * Unit tests for {@link CorsConfigurationAccessor}.
+ * Unit tests for {@link RepositoryCorsConfigurationAccessor}.
  * 
  * @author Mark Paluch
+ * @author Oliver Gierke
  * @soundtrack Aso Mamiko - Drive Me Crazy (Club Mix)
+ * @since 2.6
  */
 @RunWith(MockitoJUnitRunner.class)
-public class CorsConfigurationAccessorUnitTests {
+public class RepositoryCorsConfigurationAccessorUnitTests {
 
-	CorsConfigurationAccessor accessor;
+	RepositoryCorsConfigurationAccessor accessor;
 
 	@Mock ResourceMappings mappings;
 	@Mock Repositories repositories;
 
 	@Before
 	public void before() throws Exception {
-		accessor = new CorsConfigurationAccessor(mappings, repositories, null);
+		accessor = new RepositoryCorsConfigurationAccessor(mappings, repositories, NoOpStringValueResolver.INSTANCE);
 	}
 
 	/**
@@ -90,7 +93,10 @@ interface PlainRepository {}
 	@CrossOrigin
 	interface AnnotatedRepository {}
 
-	@CrossOrigin(origins = "http://far.far.away", allowedHeaders = "Content-type", maxAge = 1234,
-			exposedHeaders = "Accept", methods = RequestMethod.PATCH, allowCredentials = "true")
+	@CrossOrigin(origins = "http://far.far.away", //
+			allowedHeaders = "Content-type", //
+			maxAge = 1234, exposedHeaders = "Accept", //
+			methods = RequestMethod.PATCH, //
+			allowCredentials = "true")
 	interface FullyConfiguredCorsRepository {}
 }

spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/RepositoryRestHandlerMappingUnitTests.java

@@ -27,6 +27,7 @@
 import org.mockito.Mock;
 import org.mockito.runners.MockitoJUnitRunner;
 import org.springframework.data.domain.Sort;
+import org.springframework.data.repository.support.Repositories;
 import org.springframework.data.rest.core.config.EnumTranslationConfiguration;
 import org.springframework.data.rest.core.config.MetadataConfiguration;
 import org.springframework.data.rest.core.config.ProjectionDefinitionConfiguration;
@@ -57,6 +58,7 @@ public class RepositoryRestHandlerMappingUnitTests {
 	}
 
 	@Mock ResourceMappings mappings;
+	@Mock Repositories repositories;
 
 	RepositoryRestConfiguration configuration;
 	RepositoryRestHandlerMapping handlerMapping;
@@ -69,7 +71,7 @@ public void setUp() throws Exception {
 		configuration = new RepositoryRestConfiguration(new ProjectionDefinitionConfiguration(),
 				new MetadataConfiguration(), mock(EnumTranslationConfiguration.class));
 
-		handlerMapping = new RepositoryRestHandlerMapping(mappings, configuration);
+		handlerMapping = new RepositoryRestHandlerMapping(mappings, configuration, repositories);
 		handlerMapping.setApplicationContext(CONTEXT);
 
 		mockRequest = new MockHttpServletRequest();

src/main/asciidoc/configuring-cors.adoc

@@ -21,7 +21,8 @@ In the above example CORS support is enabled for the whole `PersonRepository`. `
 [source, java]
 ----
 @CrossOrigin(origins = "http://domain2.com",
-		methods = { RequestMethod.GET, RequestMethod.POST, RequestMethod.DELETE }, maxAge = 3600)
+  methods = { RequestMethod.GET, RequestMethod.POST, RequestMethod.DELETE },
+  maxAge = 3600)
 interface PersonRepository extends CrudRepository<Person, Long> {}
 ----
 
@@ -34,14 +35,13 @@ Spring Data REST fully supports http://docs.spring.io/spring/docs/current/spring
 [source, java]
 ----
 @RepositoryRestController
-@RequestMapping("/person")
 public class PersonController {
 
-	@CrossOrigin(maxAge = 3600)
-	@RequestMapping(method = RequestMethod.GET, "/xml/{id}", produces = MediaType.APPLICATION_XML_VALUE)
-	public Person retrieve(@PathVariable Long id) {
-		// ...
-	}
+  @CrossOrigin(maxAge = 3600)
+  @RequestMapping(path = "/people/xml/{id}", method = RequestMethod.GET, produces = MediaType.APPLICATION_XML_VALUE)
+  public Person retrieve(@PathVariable Long id) {
+    // …
+  }
 }
 ----
 
@@ -61,12 +61,12 @@ public class SpringDataRestCustomization extends RepositoryRestConfigurerAdapter
   @Override
   public void configureRepositoryRestConfiguration(RepositoryRestConfiguration config) {
 
-    config.addCorsMapping("/person/**")
-        .allowedOrigins("http://domain2.com")
-        .allowedMethods("PUT", "DELETE")
-        .allowedHeaders("header1", "header2", "header3")
-        .exposedHeaders("header1", "header2")
-        .allowCredentials(false).maxAge(3600);
+    config.getCorsRegistry().addCorsMapping("/person/**")
+      .allowedOrigins("http://domain2.com")
+      .allowedMethods("PUT", "DELETE")
+      .allowedHeaders("header1", "header2", "header3")
+      .exposedHeaders("header1", "header2")
+      .allowCredentials(false).maxAge(3600);
   }
 }
 ----