Apply global CORS settings to static resources in WebFlux

Closes gh-26495

spring-webflux/src/main/java/org/springframework/web/reactive/config/WebFluxConfigurationSupport.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -245,15 +245,7 @@ public class WebFluxConfigurationSupport implements ApplicationContextAware {
 
 		AbstractHandlerMapping handlerMapping = registry.getHandlerMapping();
 		if (handlerMapping != null) {
-			PathMatchConfigurer configurer = getPathMatchConfigurer();
-			Boolean useTrailingSlashMatch = configurer.isUseTrailingSlashMatch();
-			Boolean useCaseSensitiveMatch = configurer.isUseCaseSensitiveMatch();
-			if (useTrailingSlashMatch != null) {
-				handlerMapping.setUseTrailingSlashMatch(useTrailingSlashMatch);
-			}
-			if (useCaseSensitiveMatch != null) {
-				handlerMapping.setUseCaseSensitiveMatch(useCaseSensitiveMatch);
-			}
+			configureAbstractHandlerMapping(handlerMapping, getPathMatchConfigurer());
 		}
 		else {
 			handlerMapping = new EmptyHandlerMapping();

spring-webflux/src/main/java/org/springframework/web/reactive/config/WebFluxConfigurer.java

@@ -23,6 +23,7 @@ import org.springframework.http.codec.ServerCodecConfigurer;
 import org.springframework.lang.Nullable;
 import org.springframework.validation.MessageCodesResolver;
 import org.springframework.validation.Validator;
+import org.springframework.web.cors.CorsConfiguration;
 import org.springframework.web.reactive.accept.RequestedContentTypeResolverBuilder;
 import org.springframework.web.reactive.result.method.annotation.ArgumentResolverConfigurer;
 import org.springframework.web.reactive.socket.server.WebSocketService;
@@ -53,12 +54,16 @@ public interface WebFluxConfigurer {
 	}
 
 	/**
-	 * Configure "global" cross origin request processing.
-	 * <p>The configured readers and writers will apply to all requests including
-	 * annotated controllers and functional endpoints. Annotated controllers can
-	 * further declare more fine-grained configuration via
+	 * Configure "global" cross origin request processing. The configured CORS
+	 * mappings apply to annotated controllers, functional endpoints, and static
+	 * resources.
+	 * <p>Annotated controllers can further declare more fine-grained config via
 	 * {@link org.springframework.web.bind.annotation.CrossOrigin @CrossOrigin}.
+	 * In such cases "global" CORS configuration declared here is
+	 * {@link org.springframework.web.cors.CorsConfiguration#combine(CorsConfiguration) combined}
+	 * with local CORS configuration defined on a controller method.
 	 * @see CorsRegistry
+	 * @see CorsConfiguration#combine(CorsConfiguration)
 	 */
 	default void addCorsMappings(CorsRegistry registry) {
 	}

spring-webflux/src/test/java/org/springframework/web/reactive/config/DelegatingWebFluxConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -126,6 +126,7 @@ public class DelegatingWebFluxConfigurationTests {
 
 		delegatingConfig.resourceHandlerMapping(delegatingConfig.resourceUrlProvider());
 		verify(webFluxConfigurer).addResourceHandlers(any(ResourceHandlerRegistry.class));
+		verify(webFluxConfigurer).addCorsMappings(any(CorsRegistry.class));
 		verify(webFluxConfigurer).configurePathMatching(any(PathMatchConfigurer.class));
 	}
 

spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/WebMvcConfigurer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -25,6 +25,7 @@ import org.springframework.http.converter.HttpMessageConverter;
 import org.springframework.lang.Nullable;
 import org.springframework.validation.MessageCodesResolver;
 import org.springframework.validation.Validator;
+import org.springframework.web.cors.CorsConfiguration;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
 import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
 import org.springframework.web.servlet.DispatcherServlet;
@@ -104,8 +105,17 @@ public interface WebMvcConfigurer {
 	}
 
 	/**
-	 * Configure cross origin requests processing.
+	 * Configure "global" cross origin request processing. The configured CORS
+	 * mappings apply to annotated controllers, functional endpoints, and static
+	 * resources.
+	 * <p>Annotated controllers can further declare more fine-grained config via
+	 * {@link org.springframework.web.bind.annotation.CrossOrigin @CrossOrigin}.
+	 * In such cases "global" CORS configuration declared here is
+	 * {@link org.springframework.web.cors.CorsConfiguration#combine(CorsConfiguration) combined}
+	 * with local CORS configuration defined on a controller method.
 	 * @since 4.2
+	 * @see CorsRegistry
+	 * @see CorsConfiguration#combine(CorsConfiguration)
 	 */
 	default void addCorsMappings(CorsRegistry registry) {
 	}