Configurable support for static resource encodings

The new EncodedResourceResolver is a generalized version of
GzipResourceResolver that can be configured to support different
content codings, by "br" and "gzip".

GzipResourceResolver is now deprecated.

Issue: SPR-16381

spring-webflux/src/main/java/org/springframework/web/reactive/resource/CssLinkResourceTransformer.java

@@ -70,6 +70,7 @@ public class CssLinkResourceTransformer extends ResourceTransformerSupport {
 	}
 
 
+	@SuppressWarnings("deprecation")
 	@Override
 	public Mono<Resource> transform(ServerWebExchange exchange, Resource inputResource,
 			ResourceTransformerChain transformerChain) {
@@ -78,6 +79,7 @@ public class CssLinkResourceTransformer extends ResourceTransformerSupport {
 				.flatMap(ouptputResource -> {
 					String filename = ouptputResource.getFilename();
 					if (!"css".equals(StringUtils.getFilenameExtension(filename)) ||
+							inputResource instanceof EncodedResourceResolver.EncodedResource ||
 							inputResource instanceof GzipResourceResolver.GzippedResource) {
 						return Mono.just(ouptputResource);
 					}

spring-webflux/src/main/java/org/springframework/web/reactive/resource/EncodedResourceResolver.java

@@ -0,0 +1,275 @@
+/*
+ * Copyright 2002-2018 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.web.reactive.resource;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URI;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+
+import reactor.core.publisher.Mono;
+
+import org.springframework.core.io.AbstractResource;
+import org.springframework.core.io.Resource;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.server.reactive.ServerHttpRequest;
+import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
+import org.springframework.web.server.ServerWebExchange;
+
+/**
+ * Resolver that delegates to the chain, and if a resource is found, it then
+ * attempts to find an encoded (e.g. gzip, brotli) variant that is acceptable
+ * based on the "Accept-Encoding" request header.
+ *
+ * <p>The list of supported {@link #setContentCodings(List) contentCodings} can
+ * be configured, in order of preference, and each coding must be associated
+ * with {@link #setExtensions(Map) extensions}.
+ *
+ * <p>Note that this resolver must be ordered ahead of a
+ * {@link VersionResourceResolver} with a content-based, version strategy to
+ * ensure the version calculation is not impacted by the encoding.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.1
+ */
+public class EncodedResourceResolver extends AbstractResourceResolver {
+
+	private final List<String> contentCodings = new ArrayList<>(Arrays.asList("br", "gzip"));
+
+	private final Map<String, String> extensions = new LinkedHashMap<>();
+
+
+	public EncodedResourceResolver() {
+		this.extensions.put("gzip", ".gz");
+		this.extensions.put("br", ".br");
+	}
+
+
+	/**
+	 * Configure the supported content codings in order of preference. The first
+	 * coding that is present in the {@literal "Accept-Encoding"} header for a
+	 * given request, and that has a file present with the associated extension,
+	 * is used.
+	 *
+	 * <p><strong>Note:</strong> Each coding must be associated with a file
+	 * extension via {@link #registerExtension} or {@link #setExtensions}.
+	 *
+	 * <p>By default this property is set to {@literal ["br", "gzip"]}.
+	 *
+	 * @param codings one or more supported content codings
+	 */
+	public void setContentCodings(List<String> codings) {
+		Assert.notEmpty(codings, "At least one content coding expected.");
+		this.contentCodings.clear();
+		this.contentCodings.addAll(codings);
+	}
+
+	/**
+	 * Return a read-only list with the supported content codings.
+	 */
+	public List<String> getContentCodings() {
+		return Collections.unmodifiableList(this.contentCodings);
+	}
+
+	/**
+	 * Configure mappings from content codings to file extensions. A dot "."
+	 * will be prepended in front of the extension value if not present.
+	 * <p>By default this is configured with {@literal ["br" -> ".br"]} and
+	 * {@literal ["gzip" -> ".gz"]}.
+	 * @param extensions the extensions to use.
+	 * @see #registerExtension(String, String)
+	 */
+	public void setExtensions(Map<String, String> extensions) {
+		extensions.forEach(this::registerExtension);
+	}
+
+	/**
+	 * Java config friendly alternative to {@link #setExtensions(Map)}.
+	 * @param coding the content coding
+	 * @param extension the associated file extension
+	 */
+	public void registerExtension(String coding, String extension) {
+		this.extensions.put(coding, extension.startsWith(".") ? extension : "." + extension);
+	}
+
+	/**
+	 * Return a read-only map with coding-to-extension mappings.
+	 */
+	public Map<String, String> getExtensions() {
+		return Collections.unmodifiableMap(this.extensions);
+	}
+
+
+	@Override
+	protected Mono<Resource> resolveResourceInternal(@Nullable ServerWebExchange exchange,
+			String requestPath, List<? extends Resource> locations, ResourceResolverChain chain) {
+
+		return chain.resolveResource(exchange, requestPath, locations).map(resource -> {
+
+			if (exchange == null) {
+				return resource;
+			}
+
+			String acceptEncoding = getAcceptEncoding(exchange);
+			if (acceptEncoding == null) {
+				return resource;
+			}
+
+			for (String coding : this.contentCodings) {
+				if (acceptEncoding.contains(coding)) {
+					try {
+						String extension = getExtension(coding);
+						Resource encoded = new EncodedResource(resource, coding, extension);
+						if (encoded.exists()) {
+							return encoded;
+						}
+					}
+					catch (IOException ex) {
+						logger.trace("No " + coding + " resource for [" + resource.getFilename() + "]", ex);
+					}
+				}
+			}
+
+			return resource;
+		});
+	}
+
+	@Nullable
+	private String getAcceptEncoding(ServerWebExchange exchange) {
+		ServerHttpRequest request = exchange.getRequest();
+		String header = request.getHeaders().getFirst(HttpHeaders.ACCEPT_ENCODING);
+		return header != null ? header.toLowerCase() : null;
+	}
+
+	private String getExtension(String coding) {
+		String extension = this.extensions.get(coding);
+		Assert.notNull(extension, "No file extension associated with content coding " + coding);
+		return extension;
+	}
+
+	@Override
+	protected Mono<String> resolveUrlPathInternal(String resourceUrlPath,
+			List<? extends Resource> locations, ResourceResolverChain chain) {
+
+		return chain.resolveUrlPath(resourceUrlPath, locations);
+	}
+
+
+	static final class EncodedResource extends AbstractResource implements HttpResource {
+
+		private final Resource original;
+
+		private final String coding;
+
+		private final Resource encoded;
+
+
+		EncodedResource(Resource original, String coding, String extension) throws IOException {
+			this.original = original;
+			this.coding = coding;
+			this.encoded = original.createRelative(original.getFilename() + extension);
+		}
+
+		@Override
+		public InputStream getInputStream() throws IOException {
+			return this.encoded.getInputStream();
+		}
+
+		@Override
+		public boolean exists() {
+			return this.encoded.exists();
+		}
+
+		@Override
+		public boolean isReadable() {
+			return this.encoded.isReadable();
+		}
+
+		@Override
+		public boolean isOpen() {
+			return this.encoded.isOpen();
+		}
+
+		@Override
+		public boolean isFile() {
+			return this.encoded.isFile();
+		}
+
+		@Override
+		public URL getURL() throws IOException {
+			return this.encoded.getURL();
+		}
+
+		@Override
+		public URI getURI() throws IOException {
+			return this.encoded.getURI();
+		}
+
+		@Override
+		public File getFile() throws IOException {
+			return this.encoded.getFile();
+		}
+
+		@Override
+		public long contentLength() throws IOException {
+			return this.encoded.contentLength();
+		}
+
+		@Override
+		public long lastModified() throws IOException {
+			return this.encoded.lastModified();
+		}
+
+		@Override
+		public Resource createRelative(String relativePath) throws IOException {
+			return this.encoded.createRelative(relativePath);
+		}
+
+		@Override
+		@Nullable
+		public String getFilename() {
+			return this.original.getFilename();
+		}
+
+		@Override
+		public String getDescription() {
+			return this.encoded.getDescription();
+		}
+
+		@Override
+		public HttpHeaders getResponseHeaders() {
+			HttpHeaders headers;
+			if (this.original instanceof HttpResource) {
+				headers = ((HttpResource) this.original).getResponseHeaders();
+			}
+			else {
+				headers = new HttpHeaders();
+			}
+			headers.add(HttpHeaders.CONTENT_ENCODING, this.coding);
+			return headers;
+		}
+	}
+
+}

spring-webflux/src/main/java/org/springframework/web/reactive/resource/GzipResourceResolver.java

@@ -40,7 +40,9 @@ import org.springframework.web.server.ServerWebExchange;
  *
  * @author Rossen Stoyanchev
  * @since 5.0
+ * @deprecated as of 5.1 in favor of using {@link EncodedResourceResolver}.
  */
+@Deprecated
 public class GzipResourceResolver extends AbstractResourceResolver {
 
 	@Override

spring-webflux/src/test/java/org/springframework/web/reactive/resource/CssLinkResourceTransformerTests.java

@@ -145,7 +145,8 @@ public class CssLinkResourceTransformerTests {
 		MockServerWebExchange exchange = MockServerWebExchange.from(MockServerHttpRequest.get("/static/main.css"));
 		Resource original = new ClassPathResource("test/main.css", getClass());
 		createTempCopy("main.css", "main.css.gz");
-		GzipResourceResolver.GzippedResource expected = new GzipResourceResolver.GzippedResource(original);
+		EncodedResourceResolver.EncodedResource expected =
+				new EncodedResourceResolver.EncodedResource(original, "gzip", ".gz");
 		StepVerifier.create(this.transformerChain.transform(exchange, expected))
 				.expectNext(expected)
 				.expectComplete().verify();

spring-webflux/src/test/java/org/springframework/web/reactive/resource/EncodedResourceResolverTests.java

@@ -0,0 +1,172 @@
+/*
+ * Copyright 2002-2017 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.web.reactive.resource;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.time.Duration;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.zip.GZIPOutputStream;
+
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Ignore;
+import org.junit.Test;
+
+import org.springframework.cache.Cache;
+import org.springframework.cache.concurrent.ConcurrentMapCache;
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.FileSystemResource;
+import org.springframework.core.io.Resource;
+import org.springframework.mock.http.server.reactive.test.MockServerHttpRequest;
+import org.springframework.mock.web.test.server.MockServerWebExchange;
+import org.springframework.util.FileCopyUtils;
+
+import static org.junit.Assert.*;
+
+/**
+ * Unit tests for {@link EncodedResourceResolver}.
+ *
+ * @author Rossen Stoyanchev
+ */
+public class EncodedResourceResolverTests {
+
+	private static final Duration TIMEOUT = Duration.ofSeconds(5);
+
+	
+	private ResourceResolverChain resolver;
+
+	private List<Resource> locations;
+
+
+	@BeforeClass
+	public static void createGzippedResources() throws IOException {
+		createGzFile("/js/foo.js");
+		createGzFile("foo.css");
+	}
+
+	private static void createGzFile(String filePath) throws IOException {
+		Resource location = new ClassPathResource("test/", EncodedResourceResolverTests.class);
+		Resource resource = new FileSystemResource(location.createRelative(filePath).getFile());
+
+		Path gzFilePath = Paths.get(resource.getFile().getAbsolutePath() + ".gz");
+		Files.deleteIfExists(gzFilePath);
+
+		File gzFile = Files.createFile(gzFilePath).toFile();
+		GZIPOutputStream out = new GZIPOutputStream(new FileOutputStream(gzFile));
+		FileCopyUtils.copy(resource.getInputStream(), out);
+		gzFile.deleteOnExit();
+	}
+
+
+	@Before
+	public void setup() {
+		Cache cache = new ConcurrentMapCache("resourceCache");
+
+		VersionResourceResolver versionResolver = new VersionResourceResolver();
+		versionResolver.setStrategyMap(Collections.singletonMap("/**", new ContentVersionStrategy()));
+
+		List<ResourceResolver> resolvers = new ArrayList<>();
+		resolvers.add(new CachingResourceResolver(cache));
+		resolvers.add(new EncodedResourceResolver());
+		resolvers.add(versionResolver);
+		resolvers.add(new PathResourceResolver());
+		this.resolver = new DefaultResourceResolverChain(resolvers);
+
+		this.locations = new ArrayList<>();
+		this.locations.add(new ClassPathResource("test/", getClass()));
+		this.locations.add(new ClassPathResource("testalternatepath/", getClass()));
+	}
+
+
+	@Test
+	public void resolveGzipped() {
+
+		MockServerWebExchange exchange = MockServerWebExchange.from(
+				MockServerHttpRequest.get("").header("Accept-Encoding", "gzip"));
+
+		String file = "js/foo.js";
+		Resource actual = this.resolver.resolveResource(exchange, file, this.locations).block(TIMEOUT);
+
+		assertEquals(getResource(file + ".gz").getDescription(), actual.getDescription());
+		assertEquals(getResource(file).getFilename(), actual.getFilename());
+		assertTrue(actual instanceof HttpResource);
+	}
+
+	@Test
+	@Ignore // SPR-16862
+	public void resolveGzippedWithVersion() {
+
+		MockServerWebExchange exchange = MockServerWebExchange.from(
+				MockServerHttpRequest.get("").header("Accept-Encoding", "gzip"));
+
+		String file = "foo-e36d2e05253c6c7085a91522ce43a0b4.css";
+		Resource actual = this.resolver.resolveResource(exchange, file, this.locations).block(TIMEOUT);
+
+		assertEquals(getResource("foo.css.gz").getDescription(), actual.getDescription());
+		assertEquals(getResource("foo.css").getFilename(), actual.getFilename());
+		assertTrue(actual instanceof HttpResource);
+	}
+
+	@Test
+	public void resolveFromCacheWithEncodingVariants() {
+
+		// 1. Resolve, and cache .gz variant
+
+		MockServerWebExchange exchange = MockServerWebExchange.from(
+				MockServerHttpRequest.get("").header("Accept-Encoding", "gzip"));
+
+		String file = "js/foo.js";
+		Resource resolved = this.resolver.resolveResource(exchange, file, this.locations).block(TIMEOUT);
+
+		assertEquals(getResource(file + ".gz").getDescription(), resolved.getDescription());
+		assertEquals(getResource(file).getFilename(), resolved.getFilename());
+		assertTrue(resolved instanceof HttpResource);
+
+		// 2. Resolve unencoded resource
+
+		exchange = MockServerWebExchange.from(MockServerHttpRequest.get("/js/foo.js"));
+		resolved = this.resolver.resolveResource(exchange, file, this.locations).block(TIMEOUT);
+
+		assertEquals(getResource(file).getDescription(), resolved.getDescription());
+		assertEquals(getResource(file).getFilename(), resolved.getFilename());
+		assertFalse(resolved instanceof HttpResource);
+	}
+
+	@Test  // SPR-13149
+	public void resolveWithNullRequest() {
+
+		String file = "js/foo.js";
+		Resource resolved = this.resolver.resolveResource(null, file, this.locations).block(TIMEOUT);
+
+		assertEquals(getResource(file).getDescription(), resolved.getDescription());
+		assertEquals(getResource(file).getFilename(), resolved.getFilename());
+	}
+
+	private Resource getResource(String filePath) {
+		return new ClassPathResource("test/" + filePath, getClass());
+	}
+
+}

spring-webflux/src/test/java/org/springframework/web/reactive/resource/GzipResourceResolverTests.java

@@ -1,177 +0,0 @@
-/*
- * Copyright 2002-2017 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.web.reactive.resource;
-
-import java.io.File;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.nio.file.Paths;
-import java.time.Duration;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.zip.GZIPOutputStream;
-
-import org.junit.Before;
-import org.junit.BeforeClass;
-import org.junit.Test;
-
-import org.springframework.cache.Cache;
-import org.springframework.cache.concurrent.ConcurrentMapCache;
-import org.springframework.core.io.ClassPathResource;
-import org.springframework.core.io.FileSystemResource;
-import org.springframework.core.io.Resource;
-import org.springframework.mock.http.server.reactive.test.MockServerHttpRequest;
-import org.springframework.mock.web.test.server.MockServerWebExchange;
-import org.springframework.util.FileCopyUtils;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-
-
-/**
- * Unit tests for {@link GzipResourceResolver}.
- *
- * @author Rossen Stoyanchev
- */
-public class GzipResourceResolverTests {
-
-	private static final Duration TIMEOUT = Duration.ofSeconds(5);
-
-	
-	private ResourceResolverChain resolver;
-
-	private List<Resource> locations;
-
-
-	@BeforeClass
-	public static void createGzippedResources() throws IOException {
-		createGzFile("/js/foo.js");
-		createGzFile("foo-e36d2e05253c6c7085a91522ce43a0b4.css");
-	}
-
-	private static void createGzFile(String filePath) throws IOException {
-		Resource location = new ClassPathResource("test/", GzipResourceResolverTests.class);
-		Resource fileResource = new FileSystemResource(location.createRelative(filePath).getFile());
-		Path gzFilePath = Paths.get(fileResource.getFile().getAbsolutePath() + ".gz");
-		Files.deleteIfExists(gzFilePath);
-		File gzFile = Files.createFile(gzFilePath).toFile();
-		GZIPOutputStream out = new GZIPOutputStream(new FileOutputStream(gzFile));
-		FileCopyUtils.copy(fileResource.getInputStream(), out);
-		gzFile.deleteOnExit();
-	}
-
-
-	@Before
-	public void setup() {
-		Cache cache = new ConcurrentMapCache("resourceCache");
-
-		Map<String, VersionStrategy> versionStrategyMap = new HashMap<>();
-		versionStrategyMap.put("/**", new ContentVersionStrategy());
-		VersionResourceResolver versionResolver = new VersionResourceResolver();
-		versionResolver.setStrategyMap(versionStrategyMap);
-
-		List<ResourceResolver> resolvers = new ArrayList<>();
-		resolvers.add(new CachingResourceResolver(cache));
-		resolvers.add(new GzipResourceResolver());
-		resolvers.add(versionResolver);
-		resolvers.add(new PathResourceResolver());
-		this.resolver = new DefaultResourceResolverChain(resolvers);
-
-		this.locations = new ArrayList<>();
-		this.locations.add(new ClassPathResource("test/", getClass()));
-		this.locations.add(new ClassPathResource("testalternatepath/", getClass()));
-	}
-
-
-	@Test
-	public void resolveGzippedFile() throws IOException {
-		MockServerWebExchange exchange = MockServerWebExchange.from(MockServerHttpRequest.get("")
-				.header("Accept-Encoding", "gzip"));
-
-		String file = "js/foo.js";
-		Resource resolved = this.resolver.resolveResource(exchange, file, this.locations).block(TIMEOUT);
-
-		String gzFile = file+".gz";
-		Resource resource = new ClassPathResource("test/" + gzFile, getClass());
-		assertEquals(resource.getDescription(), resolved.getDescription());
-		assertEquals(new ClassPathResource("test/" + file).getFilename(), resolved.getFilename());
-		assertTrue("Expected " + resolved + " to be of type " + HttpResource.class,
-				resolved instanceof HttpResource);
-	}
-
-	@Test
-	public void resolveFingerprintedGzippedFile() throws IOException {
-		MockServerWebExchange exchange = MockServerWebExchange.from(MockServerHttpRequest.get("")
-				.header("Accept-Encoding", "gzip"));
-
-		String file = "foo-e36d2e05253c6c7085a91522ce43a0b4.css";
-		Resource resolved = this.resolver.resolveResource(exchange, file, this.locations).block(TIMEOUT);
-
-		String gzFile = file + ".gz";
-		Resource resource = new ClassPathResource("test/" + gzFile, getClass());
-		assertEquals(resource.getDescription(), resolved.getDescription());
-		assertEquals(new ClassPathResource("test/"+file).getFilename(), resolved.getFilename());
-		assertTrue("Expected " + resolved + " to be of type " + HttpResource.class,
-				resolved instanceof HttpResource);
-	}
-
-	@Test
-	public void resolveFromCacheWithEncodingVariants() throws IOException {
-		MockServerWebExchange exchange = MockServerWebExchange.from(MockServerHttpRequest.get("")
-				.header("Accept-Encoding", "gzip"));
-
-		String file = "js/foo.js";
-		Resource resolved = this.resolver.resolveResource(exchange, file, this.locations).block(TIMEOUT);
-
-		String gzFile = file+".gz";
-		Resource gzResource = new ClassPathResource("test/"+gzFile, getClass());
-		assertEquals(gzResource.getDescription(), resolved.getDescription());
-		assertEquals(new ClassPathResource("test/" + file).getFilename(), resolved.getFilename());
-		assertTrue("Expected " + resolved + " to be of type " + HttpResource.class,
-				resolved instanceof HttpResource);
-
-		// resolved resource is now cached in CachingResourceResolver
-
-		exchange = MockServerWebExchange.from(MockServerHttpRequest.get("/js/foo.js"));
-		resolved = this.resolver.resolveResource(exchange, file, this.locations).block(TIMEOUT);
-
-		Resource resource = new ClassPathResource("test/"+file, getClass());
-		assertEquals(resource.getDescription(), resolved.getDescription());
-		assertEquals(new ClassPathResource("test/" + file).getFilename(), resolved.getFilename());
-		assertFalse("Expected " + resolved + " to *not* be of type " + HttpResource.class,
-				resolved instanceof HttpResource);
-	}
-
-	@Test  // SPR-13149
-	public void resolveWithNullRequest() throws IOException {
-		String file = "js/foo.js";
-		Resource resolved = this.resolver.resolveResource(null, file, this.locations).block(TIMEOUT);
-
-		String gzFile = file+".gz";
-		Resource gzResource = new ClassPathResource("test/" + gzFile, getClass());
-		assertEquals(gzResource.getDescription(), resolved.getDescription());
-		assertEquals(new ClassPathResource("test/" + file).getFilename(), resolved.getFilename());
-		assertTrue("Expected " + resolved + " to be of type " + HttpResource.class,
-				resolved instanceof HttpResource);
-	}
-
-}

spring-webflux/src/test/resources/org/springframework/web/reactive/resource/test/foo-e36d2e05253c6c7085a91522ce43a0b4.css

@@ -1 +0,0 @@
-h1 { color:red; }

spring-webmvc/src/main/java/org/springframework/web/servlet/resource/CssLinkResourceTransformer.java

@@ -62,6 +62,7 @@ public class CssLinkResourceTransformer extends ResourceTransformerSupport {
 	}
 
 
+	@SuppressWarnings("deprecation")
 	@Override
 	public Resource transform(HttpServletRequest request, Resource resource, ResourceTransformerChain transformerChain)
 			throws IOException {
@@ -70,6 +71,7 @@ public class CssLinkResourceTransformer extends ResourceTransformerSupport {
 
 		String filename = resource.getFilename();
 		if (!"css".equals(StringUtils.getFilenameExtension(filename)) ||
+				resource instanceof EncodedResourceResolver.EncodedResource ||
 				resource instanceof GzipResourceResolver.GzippedResource) {
 			return resource;
 		}

spring-webmvc/src/main/java/org/springframework/web/servlet/resource/EncodedResourceResolver.java

@@ -0,0 +1,270 @@
+/*
+ * Copyright 2002-2018 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.web.servlet.resource;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URI;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import javax.servlet.http.HttpServletRequest;
+
+import org.springframework.core.io.AbstractResource;
+import org.springframework.core.io.Resource;
+import org.springframework.http.HttpHeaders;
+import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
+
+/**
+ * Resolver that delegates to the chain, and if a resource is found, it then
+ * attempts to find an encoded (e.g. gzip, brotli) variant that is acceptable
+ * based on the "Accept-Encoding" request header.
+ *
+ * <p>The list of supported {@link #setContentCodings(List) contentCodings} can
+ * be configured, in order of preference, and each coding must be associated
+ * with {@link #setExtensions(Map) extensions}.
+ *
+ * <p>Note that this resolver must be ordered ahead of a
+ * {@link VersionResourceResolver} with a content-based, version strategy to
+ * ensure the version calculation is not impacted by the encoding.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.1
+ */
+public class EncodedResourceResolver extends AbstractResourceResolver {
+
+	private final List<String> contentCodings = new ArrayList<>(Arrays.asList("br", "gzip"));
+
+	private final Map<String, String> extensions = new LinkedHashMap<>();
+
+
+	public EncodedResourceResolver() {
+		this.extensions.put("gzip", ".gz");
+		this.extensions.put("br", ".br");
+	}
+
+
+	/**
+	 * Configure the supported content codings in order of preference. The first
+	 * coding that is present in the {@literal "Accept-Encoding"} header for a
+	 * given request, and that has a file present with the associated extension,
+	 * is used.
+	 *
+	 * <p><strong>Note:</strong> Each coding must be associated with a file
+	 * extension via {@link #registerExtension} or {@link #setExtensions}.
+	 *
+	 * <p>By default this property is set to {@literal ["br", "gzip"]}.
+	 *
+	 * @param codings one or more supported content codings
+	 */
+	public void setContentCodings(List<String> codings) {
+		Assert.notEmpty(codings, "At least one content coding expected.");
+		this.contentCodings.clear();
+		this.contentCodings.addAll(codings);
+	}
+
+	/**
+	 * Return a read-only list with the supported content codings.
+	 */
+	public List<String> getContentCodings() {
+		return Collections.unmodifiableList(this.contentCodings);
+	}
+
+	/**
+	 * Configure mappings from content codings to file extensions. A dot "."
+	 * will be prepended in front of the extension value if not present.
+	 * <p>By default this is configured with {@literal ["br" -> ".br"]} and
+	 * {@literal ["gzip" -> ".gz"]}.
+	 * @param extensions the extensions to use.
+	 * @see #registerExtension(String, String)
+	 */
+	public void setExtensions(Map<String, String> extensions) {
+		extensions.forEach(this::registerExtension);
+	}
+
+	/**
+	 * Java config friendly alternative to {@link #setExtensions(Map)}.
+	 * @param coding the content coding
+	 * @param extension the associated file extension
+	 */
+	public void registerExtension(String coding, String extension) {
+		this.extensions.put(coding, extension.startsWith(".") ? extension : "." + extension);
+	}
+
+	/**
+	 * Return a read-only map with coding-to-extension mappings.
+	 */
+	public Map<String, String> getExtensions() {
+		return Collections.unmodifiableMap(this.extensions);
+	}
+
+
+	@Override
+	protected Resource resolveResourceInternal(@Nullable HttpServletRequest request, String requestPath,
+			List<? extends Resource> locations, ResourceResolverChain chain) {
+
+		Resource resource = chain.resolveResource(request, requestPath, locations);
+		if (resource == null || request == null) {
+			return resource;
+		}
+
+		String acceptEncoding = getAcceptEncoding(request);
+		if (acceptEncoding == null) {
+			return resource;
+		}
+
+		for (String coding : this.contentCodings) {
+			if (acceptEncoding.contains(coding)) {
+				try {
+					String extension = getExtension(coding);
+					Resource encoded = new EncodedResource(resource, coding, extension);
+					if (encoded.exists()) {
+						return encoded;
+					}
+				}
+				catch (IOException ex) {
+					logger.trace("No " + coding + " resource for [" + resource.getFilename() + "]", ex);
+				}
+			}
+		}
+
+		return resource;
+	}
+
+	@Nullable
+	private String getAcceptEncoding(HttpServletRequest request) {
+		String header = request.getHeader(HttpHeaders.ACCEPT_ENCODING);
+		return header != null ? header.toLowerCase() : null;
+	}
+
+	private String getExtension(String coding) {
+		String extension = this.extensions.get(coding);
+		Assert.notNull(extension, "No file extension associated with content coding " + coding);
+		return extension;
+	}
+
+	@Override
+	protected String resolveUrlPathInternal(String resourceUrlPath,
+			List<? extends Resource> locations, ResourceResolverChain chain) {
+
+		return chain.resolveUrlPath(resourceUrlPath, locations);
+	}
+
+
+	static final class EncodedResource extends AbstractResource implements HttpResource {
+
+		private final Resource original;
+
+		private final String coding;
+
+		private final Resource encoded;
+
+
+		EncodedResource(Resource original, String coding, String extension) throws IOException {
+			this.original = original;
+			this.coding = coding;
+			this.encoded = original.createRelative(original.getFilename() + extension);
+		}
+
+
+		@Override
+		public InputStream getInputStream() throws IOException {
+			return this.encoded.getInputStream();
+		}
+
+		@Override
+		public boolean exists() {
+			return this.encoded.exists();
+		}
+
+		@Override
+		public boolean isReadable() {
+			return this.encoded.isReadable();
+		}
+
+		@Override
+		public boolean isOpen() {
+			return this.encoded.isOpen();
+		}
+
+		@Override
+		public boolean isFile() {
+			return this.encoded.isFile();
+		}
+
+		@Override
+		public URL getURL() throws IOException {
+			return this.encoded.getURL();
+		}
+
+		@Override
+		public URI getURI() throws IOException {
+			return this.encoded.getURI();
+		}
+
+		@Override
+		public File getFile() throws IOException {
+			return this.encoded.getFile();
+		}
+
+		@Override
+		public long contentLength() throws IOException {
+			return this.encoded.contentLength();
+		}
+
+		@Override
+		public long lastModified() throws IOException {
+			return this.encoded.lastModified();
+		}
+
+		@Override
+		public Resource createRelative(String relativePath) throws IOException {
+			return this.encoded.createRelative(relativePath);
+		}
+
+		@Override
+		@Nullable
+		public String getFilename() {
+			return this.original.getFilename();
+		}
+
+		@Override
+		public String getDescription() {
+			return this.encoded.getDescription();
+		}
+
+		@Override
+		public HttpHeaders getResponseHeaders() {
+			HttpHeaders headers;
+			if (this.original instanceof HttpResource) {
+				headers = ((HttpResource) this.original).getResponseHeaders();
+			}
+			else {
+				headers = new HttpHeaders();
+			}
+			headers.add(HttpHeaders.CONTENT_ENCODING, this.coding);
+			return headers;
+		}
+	}
+
+}

spring-webmvc/src/main/java/org/springframework/web/servlet/resource/GzipResourceResolver.java

@@ -40,7 +40,9 @@ import org.springframework.lang.Nullable;
  * @author Rossen Stoyanchev
  * @author Sam Brannen
  * @since 4.1
+ * @deprecated as of 5.1 in favor of using {@link EncodedResourceResolver}.
  */
+@Deprecated
 public class GzipResourceResolver extends AbstractResourceResolver {
 
 	@Override

spring-webmvc/src/test/java/org/springframework/web/servlet/config/MvcNamespaceTests.java

@@ -112,8 +112,8 @@ import org.springframework.web.servlet.resource.CachingResourceTransformer;
 import org.springframework.web.servlet.resource.ContentVersionStrategy;
 import org.springframework.web.servlet.resource.CssLinkResourceTransformer;
 import org.springframework.web.servlet.resource.DefaultServletHttpRequestHandler;
+import org.springframework.web.servlet.resource.EncodedResourceResolver;
 import org.springframework.web.servlet.resource.FixedVersionStrategy;
-import org.springframework.web.servlet.resource.GzipResourceResolver;
 import org.springframework.web.servlet.resource.PathResourceResolver;
 import org.springframework.web.servlet.resource.ResourceHttpRequestHandler;
 import org.springframework.web.servlet.resource.ResourceResolver;
@@ -140,16 +140,8 @@ import org.springframework.web.servlet.view.tiles3.TilesConfigurer;
 import org.springframework.web.servlet.view.tiles3.TilesViewResolver;
 import org.springframework.web.util.UrlPathHelper;
 
-import static org.hamcrest.Matchers.containsInAnyOrder;
-import static org.hamcrest.Matchers.instanceOf;
-import static org.junit.Assert.assertArrayEquals;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertSame;
-import static org.junit.Assert.assertThat;
-import static org.junit.Assert.assertTrue;
+import static org.hamcrest.Matchers.*;
+import static org.junit.Assert.*;
 
 /**
  * Tests loading actual MVC namespace configuration.
@@ -474,7 +466,7 @@ public class MvcNamespaceTests {
 		List<ResourceResolver> resolvers = handler.getResourceResolvers();
 		assertThat(resolvers, Matchers.hasSize(3));
 		assertThat(resolvers.get(0), Matchers.instanceOf(VersionResourceResolver.class));
-		assertThat(resolvers.get(1), Matchers.instanceOf(GzipResourceResolver.class));
+		assertThat(resolvers.get(1), Matchers.instanceOf(EncodedResourceResolver.class));
 		assertThat(resolvers.get(2), Matchers.instanceOf(PathResourceResolver.class));
 
 		VersionResourceResolver versionResolver = (VersionResourceResolver) resolvers.get(0);

spring-webmvc/src/test/java/org/springframework/web/servlet/resource/CssLinkResourceTransformerTests.java

@@ -144,7 +144,8 @@ public class CssLinkResourceTransformerTests {
 		this.request = new MockHttpServletRequest("GET", "/static/main.css");
 		Resource original = new ClassPathResource("test/main.css", getClass());
 		createTempCopy("main.css", "main.css.gz");
-		GzipResourceResolver.GzippedResource expected = new GzipResourceResolver.GzippedResource(original);
+		EncodedResourceResolver.EncodedResource expected =
+				new EncodedResourceResolver.EncodedResource(original, "gzip", ".gz");
 		Resource actual = this.transformerChain.transform(this.request, expected);
 		assertSame(expected, actual);
 	}

spring-webmvc/src/test/java/org/springframework/web/servlet/resource/EncodedResourceResolverTests.java

@@ -0,0 +1,160 @@
+/*
+ * Copyright 2002-2018 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.web.servlet.resource;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.zip.GZIPOutputStream;
+
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import org.springframework.cache.Cache;
+import org.springframework.cache.concurrent.ConcurrentMapCache;
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.FileSystemResource;
+import org.springframework.core.io.Resource;
+import org.springframework.mock.web.test.MockHttpServletRequest;
+import org.springframework.util.FileCopyUtils;
+
+import static org.junit.Assert.*;
+
+/**
+ * Unit tests for {@link EncodedResourceResolver}.
+ *
+ * @author Jeremy Grelle
+ * @author Rossen Stoyanchev
+ */
+public class EncodedResourceResolverTests {
+
+	private ResourceResolverChain resolver;
+
+	private List<Resource> locations;
+
+	private Cache cache;
+
+
+	@BeforeClass
+	public static void createGzippedResources() throws IOException {
+		createGzipFile("/js/foo.js");
+		createGzipFile("foo.css");
+	}
+
+	private static void createGzipFile(String filePath) throws IOException {
+		Resource location = new ClassPathResource("test/", EncodedResourceResolverTests.class);
+		Resource resource = new FileSystemResource(location.createRelative(filePath).getFile());
+
+		Path gzFilePath = Paths.get(resource.getFile().getAbsolutePath() + ".gz");
+		Files.deleteIfExists(gzFilePath);
+
+		File gzFile = Files.createFile(gzFilePath).toFile();
+		GZIPOutputStream out = new GZIPOutputStream(new FileOutputStream(gzFile));
+		FileCopyUtils.copy(resource.getInputStream(), out);
+		gzFile.deleteOnExit();
+	}
+
+
+	@Before
+	public void setUp() {
+		this.cache = new ConcurrentMapCache("resourceCache");
+
+		VersionResourceResolver versionResolver = new VersionResourceResolver();
+		versionResolver.setStrategyMap(Collections.singletonMap("/**", new ContentVersionStrategy()));
+
+		List<ResourceResolver> resolvers = new ArrayList<>();
+		resolvers.add(new CachingResourceResolver(this.cache));
+		resolvers.add(new EncodedResourceResolver());
+		resolvers.add(versionResolver);
+		resolvers.add(new PathResourceResolver());
+		this.resolver = new DefaultResourceResolverChain(resolvers);
+
+		this.locations = new ArrayList<>();
+		this.locations.add(new ClassPathResource("test/", getClass()));
+		this.locations.add(new ClassPathResource("testalternatepath/", getClass()));
+	}
+
+
+	@Test
+	public void resolveGzipped() {
+		String file = "js/foo.js";
+		MockHttpServletRequest request = new MockHttpServletRequest();
+		request.addHeader("Accept-Encoding", "gzip");
+		Resource actual = this.resolver.resolveResource(request, file, this.locations);
+
+		assertEquals(getResource(file + ".gz").getDescription(), actual.getDescription());
+		assertEquals(getResource(file).getFilename(), actual.getFilename());
+		assertTrue(actual instanceof HttpResource);
+	}
+
+	@Test
+	public void resolveGzippedWithVersion() {
+		String file = "foo-e36d2e05253c6c7085a91522ce43a0b4.css";
+		MockHttpServletRequest request = new MockHttpServletRequest();
+		request.addHeader("Accept-Encoding", "gzip");
+		Resource resolved = this.resolver.resolveResource(request, file, this.locations);
+
+		assertEquals(getResource("foo.css.gz").getDescription(), resolved.getDescription());
+		assertEquals(getResource("foo.css").getFilename(), resolved.getFilename());
+		assertTrue(resolved instanceof HttpResource);
+	}
+
+	@Test
+	public void resolveFromCacheWithEncodingVariants() {
+
+		// 1. Resolve, and cache .gz variant
+
+		String file = "js/foo.js";
+		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/js/foo.js");
+		request.addHeader("Accept-Encoding", "gzip");
+		Resource resolved = this.resolver.resolveResource(request, file, this.locations);
+
+		assertEquals(getResource(file + ".gz").getDescription(), resolved.getDescription());
+		assertEquals(getResource(file).getFilename(), resolved.getFilename());
+		assertTrue(resolved instanceof HttpResource);
+
+		// 2. Resolve unencoded resource
+
+		request = new MockHttpServletRequest("GET", "/js/foo.js");
+		resolved = this.resolver.resolveResource(request, file, this.locations);
+
+		assertEquals(getResource(file).getDescription(), resolved.getDescription());
+		assertEquals(getResource(file).getFilename(), resolved.getFilename());
+		assertFalse(resolved instanceof HttpResource);
+	}
+
+	@Test // SPR-13149
+	public void resolveWithNullRequest() {
+		String file = "js/foo.js";
+		Resource resolved = this.resolver.resolveResource(null, file, this.locations);
+
+		assertEquals(getResource(file).getDescription(), resolved.getDescription());
+		assertEquals(getResource(file).getFilename(), resolved.getFilename());
+	}
+
+	private Resource getResource(String filePath) {
+		return new ClassPathResource("test/" + filePath, getClass());
+	}
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/resource/GzipResourceResolverTests.java

@@ -1,172 +0,0 @@
-/*
- * Copyright 2002-2016 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.web.servlet.resource;
-
-import java.io.File;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.nio.file.Paths;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.zip.GZIPOutputStream;
-
-import org.junit.Before;
-import org.junit.BeforeClass;
-import org.junit.Test;
-
-import org.springframework.cache.Cache;
-import org.springframework.cache.concurrent.ConcurrentMapCache;
-import org.springframework.core.io.ClassPathResource;
-import org.springframework.core.io.FileSystemResource;
-import org.springframework.core.io.Resource;
-import org.springframework.mock.web.test.MockHttpServletRequest;
-import org.springframework.util.FileCopyUtils;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-
-
-/**
- * Unit tests for {@link GzipResourceResolver}.
- *
- * @author Jeremy Grelle
- * @author Rossen Stoyanchev
- */
-public class GzipResourceResolverTests {
-
-	private ResourceResolverChain resolver;
-
-	private List<Resource> locations;
-
-	private Cache cache;
-
-
-	@BeforeClass
-	public static void createGzippedResources() throws IOException {
-		createGzFile("/js/foo.js");
-		createGzFile("foo-e36d2e05253c6c7085a91522ce43a0b4.css");
-	}
-
-	private static void createGzFile(String filePath) throws IOException {
-		Resource location = new ClassPathResource("test/", GzipResourceResolverTests.class);
-		Resource fileResource = new FileSystemResource(location.createRelative(filePath).getFile());
-		Path gzFilePath = Paths.get(fileResource.getFile().getAbsolutePath() + ".gz");
-		Files.deleteIfExists(gzFilePath);
-		File gzFile = Files.createFile(gzFilePath).toFile();
-		GZIPOutputStream out = new GZIPOutputStream(new FileOutputStream(gzFile));
-		FileCopyUtils.copy(fileResource.getInputStream(), out);
-		gzFile.deleteOnExit();
-	}
-
-
-	@Before
-	public void setUp() {
-		this.cache = new ConcurrentMapCache("resourceCache");
-
-		Map<String, VersionStrategy> versionStrategyMap = new HashMap<>();
-		versionStrategyMap.put("/**", new ContentVersionStrategy());
-		VersionResourceResolver versionResolver = new VersionResourceResolver();
-		versionResolver.setStrategyMap(versionStrategyMap);
-
-		List<ResourceResolver> resolvers = new ArrayList<>();
-		resolvers.add(new CachingResourceResolver(this.cache));
-		resolvers.add(new GzipResourceResolver());
-		resolvers.add(versionResolver);
-		resolvers.add(new PathResourceResolver());
-		this.resolver = new DefaultResourceResolverChain(resolvers);
-
-		this.locations = new ArrayList<>();
-		this.locations.add(new ClassPathResource("test/", getClass()));
-		this.locations.add(new ClassPathResource("testalternatepath/", getClass()));
-	}
-
-
-	@Test
-	public void resolveGzippedFile() throws IOException {
-		MockHttpServletRequest request = new MockHttpServletRequest();
-		request.addHeader("Accept-Encoding", "gzip");
-		String file = "js/foo.js";
-		Resource resolved = this.resolver.resolveResource(request, file, this.locations);
-
-		String gzFile = file + ".gz";
-		Resource resource = new ClassPathResource("test/"+gzFile, getClass());
-		assertEquals(resource.getDescription(), resolved.getDescription());
-		assertEquals(new ClassPathResource("test/" + file).getFilename(), resolved.getFilename());
-		assertTrue("Expected " + resolved + " to be of type " + HttpResource.class,
-				resolved instanceof HttpResource);
-	}
-
-	@Test
-	public void resolveFingerprintedGzippedFile() throws IOException {
-		MockHttpServletRequest request = new MockHttpServletRequest();
-		request.addHeader("Accept-Encoding", "gzip");
-		String file = "foo-e36d2e05253c6c7085a91522ce43a0b4.css";
-		Resource resolved = this.resolver.resolveResource(request, file, this.locations);
-
-		String gzFile = file + ".gz";
-		Resource resource = new ClassPathResource("test/"+gzFile, getClass());
-		assertEquals(resource.getDescription(), resolved.getDescription());
-		assertEquals(new ClassPathResource("test/"+file).getFilename(), resolved.getFilename());
-		assertTrue("Expected " + resolved + " to be of type " + HttpResource.class,
-				resolved instanceof HttpResource);
-	}
-
-	@Test
-	public void resolveFromCacheWithEncodingVariants() throws IOException {
-		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/js/foo.js");
-		request.addHeader("Accept-Encoding", "gzip");
-		String file = "js/foo.js";
-		Resource resolved = this.resolver.resolveResource(request, file, this.locations);
-
-		String gzFile = file + ".gz";
-		Resource gzResource = new ClassPathResource("test/"+gzFile, getClass());
-		assertEquals(gzResource.getDescription(), resolved.getDescription());
-		assertEquals(new ClassPathResource("test/" + file).getFilename(), resolved.getFilename());
-		assertTrue("Expected " + resolved + " to be of type " + HttpResource.class,
-				resolved instanceof HttpResource);
-
-		// resolved resource is now cached in CachingResourceResolver
-
-		request = new MockHttpServletRequest("GET", "/js/foo.js");
-		resolved = this.resolver.resolveResource(request, file, this.locations);
-
-		Resource resource = new ClassPathResource("test/"+file, getClass());
-		assertEquals(resource.getDescription(), resolved.getDescription());
-		assertEquals(new ClassPathResource("test/" + file).getFilename(), resolved.getFilename());
-		assertFalse("Expected " + resolved + " to *not* be of type " + HttpResource.class,
-				resolved instanceof HttpResource);
-	}
-
-	@Test // SPR-13149
-	public void resolveWithNullRequest() throws IOException {
-		String file = "js/foo.js";
-		Resource resolved = this.resolver.resolveResource(null, file, this.locations);
-
-		String gzFile = file+".gz";
-		Resource gzResource = new ClassPathResource("test/"+gzFile, getClass());
-		assertEquals(gzResource.getDescription(), resolved.getDescription());
-		assertEquals(new ClassPathResource("test/" + file).getFilename(), resolved.getFilename());
-		assertTrue("Expected " + resolved + " to be of type " + HttpResource.class,
-				resolved instanceof HttpResource);
-	}
-
-}

spring-webmvc/src/test/resources/org/springframework/web/servlet/config/mvc-config-resources-chain-no-auto.xml

@@ -15,7 +15,7 @@
 						<bean class="org.springframework.web.servlet.resource.ContentVersionStrategy" />
 					</mvc:version-strategy>
 				</mvc:version-resolver>
-				<ref bean="gzipResourceResolver"/>
+				<ref bean="encodedResourceResolver"/>
 				<bean class="org.springframework.web.servlet.resource.PathResourceResolver"/>
 			</mvc:resolvers>
 			<mvc:transformers>
@@ -27,7 +27,7 @@
 		</mvc:resource-chain>
 	</mvc:resources>
 
-	<bean id="gzipResourceResolver" class="org.springframework.web.servlet.resource.GzipResourceResolver" />
+	<bean id="encodedResourceResolver" class="org.springframework.web.servlet.resource.EncodedResourceResolver" />
 	<bean id="resourceCache" class="org.springframework.cache.concurrent.ConcurrentMapCache">
 		<constructor-arg name="name" value="resourceCache"/>
 	</bean>

spring-webmvc/src/test/resources/org/springframework/web/servlet/resource/test/foo-e36d2e05253c6c7085a91522ce43a0b4.css

@@ -1 +0,0 @@
-h1 { color:red; }

src/docs/asciidoc/web/webflux.adoc

@@ -2914,6 +2914,10 @@ of resolvers and transformers (e.g. resources on Amazon S3). When serving only l
 resources the workaround is to use `ResourceUrlProvider` directly (e.g. through a custom
 tag) and block for 0 seconds.
 
+Note that when using both `EncodedResourceResolver` (e.g. for serving gzipped or brotli
+encoded resources) and `VersionedResourceResolver`, they must be registered in this order.
+That ensures content based versions are always computed reliably based on the unencoded file.
+
 http://www.webjars.org/documentation[WebJars] is also supported via `WebJarsResourceResolver`
 and automatically registered when `"org.webjars:webjars-locator"` is present on the
 classpath. The resolver can re-write URLs to include the version of the jar and can also

src/docs/asciidoc/web/webmvc.adoc

@@ -4549,12 +4549,16 @@ In XML, the same:
 </mvc:resources>
 ----
 
-You can use `ResourceUrlProvider` to rewrite URLs and apply the full chain of resolvers and
+You can then use `ResourceUrlProvider` to rewrite URLs and apply the full chain of resolvers and
 transformers -- e.g. to insert versions. The MVC config provides a `ResourceUrlProvider`
 bean so it can be injected into others. You can also make the rewrite transparent with the
 `ResourceUrlEncodingFilter` for Thymeleaf, JSPs, FreeMarker, and others with URL tags that
 rely on `HttpServletResponse#encodeURL`.
 
+Note that when using both `EncodedResourceResolver` (e.g. for serving gzipped or brotli
+encoded resources) and `VersionedResourceResolver`, they must be registered in this order.
+That ensures content based versions are always computed reliably based on the unencoded file.
+
 http://www.webjars.org/documentation[WebJars] is also supported via `WebJarsResourceResolver`
 and automatically registered when `"org.webjars:webjars-locator"` is present on the
 classpath. The resolver can re-write URLs to include the version of the jar and can also