allow @CollectionFormat on class level (#596) (#610)

docs/src/main/asciidoc/spring-cloud-openfeign.adoc

@@ -692,20 +692,21 @@ public interface DemoTemplate {
 ----
 
 === Feign `CollectionFormat` support
-We support `feign.CollectionFormat` by providing the `@CollectionFormat` annotation.You can annotate a Feign client method with it by passing the desired `feign.CollectionFormat` as annotation value.
+We support `feign.CollectionFormat` by providing the `@CollectionFormat` annotation.
+You can annotate a Feign client method (or the whole class to affect all methods) with it by passing the desired `feign.CollectionFormat` as annotation value.
 
 In the following example, the `CSV` format is used instead of the default `EXPLODED` to process the method.
 
 [source,java,indent=0]
 ----
 @FeignClient(name = "demo")
-	protected interface PageableFeignClient {
+protected interface PageableFeignClient {
 
-		@CollectionFormat(feign.CollectionFormat.CSV)
-		@GetMapping(path = "/page")
-		ResponseEntity performRequest(Pageable page);
+    @CollectionFormat(feign.CollectionFormat.CSV)
+    @GetMapping(path = "/page")
+    ResponseEntity performRequest(Pageable page);
 
-	}
+}
 ----
 
 TIP: Set the `CSV` format while sending `Pageable` as a query parameter in order for it to be encoded correctly.

spring-cloud-openfeign-core/src/main/java/org/springframework/cloud/openfeign/CollectionFormat.java

@@ -25,9 +25,10 @@ import java.lang.annotation.Target;
  * Indicates which collection format should be used while processing the annotated method.
  *
  * @author Olga Maciaszek-Sharma
+ * @author Sam Kruglov
  * @see feign.CollectionFormat
  */
-@Target(ElementType.METHOD)
+@Target({ElementType.METHOD, ElementType.TYPE})
 @Retention(RetentionPolicy.RUNTIME)
 public @interface CollectionFormat {
 

spring-cloud-openfeign-core/src/main/java/org/springframework/cloud/openfeign/support/SpringMvcContract.java

@@ -80,6 +80,7 @@ import static org.springframework.core.annotation.AnnotatedElementUtils.findMerg
  * @author Artyom Romanenko
  * @author Darren Foong
  * @author Ram Anaswara
+ * @author Sam Kruglov
  */
 public class SpringMvcContract extends Contract.BaseContract implements ResourceLoaderAware {
 
@@ -171,11 +172,11 @@ public class SpringMvcContract extends Contract.BaseContract implements Resource
 	@Override
 	protected void processAnnotationOnClass(MethodMetadata data, Class<?> clz) {
 		if (clz.getInterfaces().length == 0) {
-			RequestMapping classAnnotation = findMergedAnnotation(clz, RequestMapping.class);
-			if (classAnnotation != null) {
+			RequestMapping requestMapping = findMergedAnnotation(clz, RequestMapping.class);
+			if (requestMapping != null) {
 				// Prepend path from class annotation if specified
-				if (classAnnotation.value().length > 0) {
-					String pathValue = emptyToNull(classAnnotation.value()[0]);
+				if (requestMapping.value().length > 0) {
+					String pathValue = emptyToNull(requestMapping.value()[0]);
 					pathValue = resolve(pathValue);
 					if (!pathValue.startsWith("/")) {
 						pathValue = "/" + pathValue;
@@ -186,6 +187,10 @@ public class SpringMvcContract extends Contract.BaseContract implements Resource
 					}
 				}
 			}
+			CollectionFormat collectionFormat = findMergedAnnotation(clz, CollectionFormat.class);
+			if (collectionFormat != null) {
+				data.template().collectionFormat(collectionFormat.value());
+			}
 		}
 	}
 

spring-cloud-openfeign-core/src/test/java/org/springframework/cloud/openfeign/support/SpringMvcContractTests.java

@@ -62,6 +62,7 @@ import org.springframework.web.multipart.MultipartFile;
 
 import static com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility.ANY;
 import static com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility.NONE;
+import static feign.CollectionFormat.CSV;
 import static feign.CollectionFormat.SSV;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.Assume.assumeTrue;
@@ -73,6 +74,7 @@ import static org.junit.Assume.assumeTrue;
  * @author Aaron Whiteside
  * @author Artyom Romanenko
  * @author Olga Maciaszek-Sharma
+ * @author Sam Kruglov
  */
 public class SpringMvcContractTests {
 
@@ -302,6 +304,15 @@ public class SpringMvcContractTests {
 		assertThat(data.template().collectionFormat()).isEqualTo(SSV);
 	}
 
+	@Test
+	public void processAnnotationOnClass_CollectionFormat() throws NoSuchMethodException {
+		Method method = TestTemplate_Advanced.class.getDeclaredMethod("getWithoutCollectionFormat");
+
+		MethodMetadata data = contract.parseAndValidateMetadata(method.getDeclaringClass(), method);
+
+		assertThat(data.template().collectionFormat()).isEqualTo(CSV);
+	}
+
 	@Test
 	public void testProcessAnnotations_Advanced() throws Exception {
 		Method method = TestTemplate_Advanced.class.getDeclaredMethod("getTest", String.class, String.class,
@@ -744,12 +755,16 @@ public class SpringMvcContractTests {
 
 	@JsonAutoDetect
 	@RequestMapping("/advanced")
+	@CollectionFormat(CSV)
 	public interface TestTemplate_Advanced {
 
 		@CollectionFormat(SSV)
 		@GetMapping
 		ResponseEntity<TestObject> getWithCollectionFormat();
 
+		@GetMapping
+		ResponseEntity<TestObject> getWithoutCollectionFormat();
+
 		@ExceptionHandler
 		@PutMapping(path = "/test/{id}", produces = MediaType.APPLICATION_JSON_VALUE)
 		ResponseEntity<TestObject> getTest(@RequestHeader("Authorization") String auth, @PathVariable("id") String id,