DATAREST-333 - Added controller mappings for OPTIONS requests.

The root resource, collection and item resources as well as the search and query method resources now expose a handler method to handle OPTIONS requests and return a response with the Allow header set to the HTTP methods appropriate to the resource requested.

Added some additional methods for HEAD requests and a few integration tests for functionality that previously existed.

Related ticket: DATAREST-330.

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

@@ -45,6 +45,7 @@
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.converter.HttpMessageNotReadableException;
+import org.springframework.util.Assert;
 import org.springframework.web.HttpRequestMethodNotSupportedException;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.ResponseBody;
@@ -61,7 +62,14 @@ class AbstractRepositoryRestController implements MessageSourceAware {
 	private final PagedResourcesAssembler<Object> pagedResourcesAssembler;
 	private MessageSourceAccessor messageSourceAccessor;
 
+	/**
+	 * Creates a new {@link AbstractRepositoryRestController} for the given {@link PagedResourcesAssembler}.
+	 * 
+	 * @param pagedResourcesAssembler must not be {@literal null}.
+	 */
 	public AbstractRepositoryRestController(PagedResourcesAssembler<Object> pagedResourcesAssembler) {
+
+		Assert.notNull(pagedResourcesAssembler, "PagedResourcesAssembler must not be null!");
 		this.pagedResourcesAssembler = pagedResourcesAssembler;
 	}
 

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

@@ -15,46 +15,94 @@
  */
 package org.springframework.data.rest.webmvc;
 
+import java.util.Collections;
+
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.data.repository.support.Repositories;
 import org.springframework.data.rest.core.mapping.ResourceMappings;
 import org.springframework.data.rest.core.mapping.ResourceMetadata;
 import org.springframework.data.web.PagedResourcesAssembler;
 import org.springframework.hateoas.EntityLinks;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.util.Assert;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
-import org.springframework.web.bind.annotation.ResponseBody;
 
 /**
+ * Controller for the root resource exposing links to the repository resources.
+ * 
  * @author Jon Brisbin
  * @author Oliver Gierke
  */
 @RepositoryRestController
+@RequestMapping("/")
 public class RepositoryController extends AbstractRepositoryRestController {
 
 	private final Repositories repositories;
 	private final EntityLinks entityLinks;
 	private final ResourceMappings mappings;
 
+	/**
+	 * Creates a new {@link RepositoryController} for the given {@link PagedResourcesAssembler}, {@link Repositories},
+	 * {@link EntityLinks} and {@link ResourceMappings}.
+	 * 
+	 * @param assembler must not be {@literal null}.
+	 * @param repositories must not be {@literal null}.
+	 * @param entityLinks must not be {@literal null}.
+	 * @param mappings must not be {@literal null}.
+	 */
 	@Autowired
 	public RepositoryController(PagedResourcesAssembler<Object> assembler, Repositories repositories,
 			EntityLinks entityLinks, ResourceMappings mappings) {
 
 		super(assembler);
 
+		Assert.notNull(repositories, "Repositories must not be null!");
+		Assert.notNull(entityLinks, "EntityLinks must not be null!");
+		Assert.notNull(mappings, "ResourceMappings must not be null!");
+
 		this.repositories = repositories;
 		this.entityLinks = entityLinks;
 		this.mappings = mappings;
 	}
 
+	/**
+	 * <code>OPTIONS /</code>.
+	 * 
+	 * @return
+	 * @since 2.2
+	 */
+	@RequestMapping(method = RequestMethod.OPTIONS)
+	public HttpEntity<?> optionsForRepositories() {
+
+		HttpHeaders headers = new HttpHeaders();
+		headers.setAllow(Collections.singleton(HttpMethod.GET));
+
+		return new ResponseEntity<Object>(headers, HttpStatus.OK);
+	}
+
+	/**
+	 * <code>HEAD /</code>
+	 * 
+	 * @return
+	 * @since 2.2
+	 */
+	@RequestMapping(method = RequestMethod.HEAD)
+	public ResponseEntity<?> headForRepositories() {
+		return new ResponseEntity<Object>(HttpStatus.NO_CONTENT);
+	}
+
 	/**
 	 * Lists all repositories exported by creating a link list pointing to resources exposing the repositories.
 	 * 
 	 * @return
 	 */
-	@ResponseBody
-	@RequestMapping(value = "/", method = RequestMethod.GET)
-	public RepositoryLinksResource listRepositories() {
+	@RequestMapping(method = RequestMethod.GET)
+	public HttpEntity<RepositoryLinksResource> listRepositories() {
 
 		RepositoryLinksResource resource = new RepositoryLinksResource();
 
@@ -66,6 +114,6 @@ public RepositoryLinksResource listRepositories() {
 			}
 		}
 
-		return resource;
+		return new ResponseEntity<RepositoryLinksResource>(resource, HttpStatus.OK);
 	}
 }

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

@@ -101,12 +101,29 @@ public void setApplicationEventPublisher(ApplicationEventPublisher publisher) {
 		this.publisher = publisher;
 	}
 
+	/**
+	 * <code>OPTIONS /{repository}</code>.
+	 * 
+	 * @param information
+	 * @return
+	 * @since 2.2
+	 */
+	@RequestMapping(value = BASE_MAPPING, method = RequestMethod.OPTIONS)
+	public ResponseEntity<?> optionsForCollectionResource(RootResourceInformation information) {
+
+		HttpHeaders headers = new HttpHeaders();
+		headers.setAllow(information.getSupportedMethods(ResourceType.COLLECTION));
+
+		return new ResponseEntity<Object>(headers, HttpStatus.OK);
+	}
+
 	/**
 	 * <code>HEAD /{repository}</code>
 	 * 
 	 * @param resourceInformation
 	 * @return
 	 * @throws HttpRequestMethodNotSupportedException
+	 * @since 2.2
 	 */
 	@RequestMapping(value = BASE_MAPPING, method = RequestMethod.HEAD)
 	public ResponseEntity<?> headCollectionResource(RootResourceInformation resourceInformation)
@@ -214,16 +231,33 @@ public ResponseEntity<ResourceSupport> postCollectionResource(RootResourceInform
 		return createAndReturn(payload.getContent(), resourceInformation.getInvoker(), assembler);
 	}
 
+	/**
+	 * <code>OPTIONS /{repository}/{id}<code>
+	 * 
+	 * @param information
+	 * @return
+	 * @since 2.2
+	 */
+	@RequestMapping(value = BASE_MAPPING + "/{id}", method = RequestMethod.OPTIONS)
+	public ResponseEntity<?> optionsForItemResource(RootResourceInformation information) {
+
+		HttpHeaders headers = new HttpHeaders();
+		headers.setAllow(information.getSupportedMethods(ResourceType.ITEM));
+
+		return new ResponseEntity<Object>(headers, HttpStatus.OK);
+	}
+
 	/**
 	 * <code>HEAD /{repsoitory}/{id}</code>
 	 * 
 	 * @param resourceInformation
 	 * @param id
 	 * @return
 	 * @throws HttpRequestMethodNotSupportedException
+	 * @since 2.2
 	 */
 	@RequestMapping(value = BASE_MAPPING + "/{id}", method = RequestMethod.HEAD)
-	public ResponseEntity<?> headItemResource(RootResourceInformation resourceInformation, @BackendId Serializable id)
+	public ResponseEntity<?> headForItemResource(RootResourceInformation resourceInformation, @BackendId Serializable id)
 			throws HttpRequestMethodNotSupportedException {
 
 		if (getItemResource(resourceInformation, id) != null) {

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

@@ -20,6 +20,7 @@
 import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 
@@ -38,6 +39,8 @@
 import org.springframework.hateoas.ResourceSupport;
 import org.springframework.hateoas.Resources;
 import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.util.Assert;
@@ -88,6 +91,24 @@ public RepositorySearchController(PagedResourcesAssembler<Object> assembler, Ent
 		this.assembler = assembler;
 	}
 
+	/**
+	 * <code>OPTIONS /{repository}/search</code>.
+	 * 
+	 * @param resourceInformation
+	 * @return
+	 * @since 2.2
+	 */
+	@RequestMapping(value = BASE_MAPPING, method = RequestMethod.OPTIONS)
+	public HttpEntity<?> optionsForSearches(RootResourceInformation resourceInformation) {
+
+		verifySearchesExposed(resourceInformation);
+
+		HttpHeaders headers = new HttpHeaders();
+		headers.setAllow(Collections.singleton(HttpMethod.GET));
+
+		return new ResponseEntity<Object>(headers, HttpStatus.OK);
+	}
+
 	/**
 	 * <code>HEAD /{repository}/search</code> - Checks whether the search resource is present.
 	 * 
@@ -187,12 +208,32 @@ public ResourceSupport executeSearchCompact(RootResourceInformation resourceInfo
 		return new Resources<Resource<?>>(EMPTY_RESOURCE_LIST, links);
 	}
 
+	/**
+	 * <code>OPTIONS /{repository}/search/{search}</code>.
+	 * 
+	 * @param information
+	 * @param search
+	 * @return
+	 * @since 2.2
+	 */
+	@RequestMapping(value = BASE_MAPPING + "/{search}", method = RequestMethod.OPTIONS)
+	public ResponseEntity<Object> optionsForSearch(RootResourceInformation information, @PathVariable String search) {
+
+		checkExecutability(information, search);
+
+		HttpHeaders headers = new HttpHeaders();
+		headers.setAllow(Collections.singleton(HttpMethod.GET));
+
+		return new ResponseEntity<Object>(headers, HttpStatus.OK);
+	}
+
 	/**
 	 * Handles a {@code HEAD} request for individual searches.
 	 * 
 	 * @param information
 	 * @param search
 	 * @return
+	 * @since 2.2
 	 */
 	@RequestMapping(value = BASE_MAPPING + "/{search}", method = RequestMethod.HEAD)
 	public ResponseEntity<Object> headForSearch(RootResourceInformation information, @PathVariable String search) {

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

@@ -80,7 +80,7 @@ public RepositoryInvoker getInvoker() {
 	 * @param resourcType must not be {@literal null}.
 	 * @return
 	 */
-	public Collection<HttpMethod> getSupportedMethods(ResourceType resourcType) {
+	public Set<HttpMethod> getSupportedMethods(ResourceType resourcType) {
 
 		Assert.notNull(resourcType, "Resource type must not be null!");
 
@@ -89,6 +89,7 @@ public Collection<HttpMethod> getSupportedMethods(ResourceType resourcType) {
 		}
 
 		Set<HttpMethod> methods = new HashSet<HttpMethod>();
+		methods.add(HttpMethod.OPTIONS);
 
 		switch (resourcType) {
 			case COLLECTION:

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

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2014 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.rest.webmvc;
+
+import static org.hamcrest.Matchers.*;
+import static org.junit.Assert.*;
+import static org.springframework.data.rest.webmvc.WebTestUtils.*;
+
+import org.junit.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.rest.webmvc.jpa.JpaRepositoryConfig;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.transaction.annotation.Transactional;
+
+/**
+ * Integration tests for {@link RepositoryController}.
+ * 
+ * @author Oliver Gierke
+ */
+@ContextConfiguration(classes = JpaRepositoryConfig.class)
+@Transactional
+public class RepositoryControllerIntegrationTests extends AbstractControllerIntegrationTests {
+
+	@Autowired RepositoryController controller;
+
+	/**
+	 * @see DATAREST-333
+	 */
+	@Test
+	public void rootResourceExposesGetOnly() {
+
+		HttpEntity<?> response = controller.optionsForRepositories();
+		assertAllowHeaders(response, HttpMethod.GET);
+	}
+
+	/**
+	 * @see DATAREST-333, DATAREST-330
+	 */
+	@Test
+	public void headRequestReturnsNoContent() {
+		assertThat(controller.headForRepositories().getStatusCode(), is(HttpStatus.NO_CONTENT));
+	}
+
+	@Test
+	public void exposesLinksToRepositories() {
+
+		RepositoryLinksResource resource = controller.listRepositories().getBody();
+
+		assertThat(resource.getLinks(), hasSize(5));
+
+		assertThat(resource.hasLink("people"), is(true));
+		assertThat(resource.hasLink("orders"), is(true));
+		assertThat(resource.hasLink("addresses"), is(true));
+		assertThat(resource.hasLink("books"), is(true));
+		assertThat(resource.hasLink("authors"), is(true));
+	}
+}