Respect context path in WebMvc.fn & WebFlux.fn

This commit makes several changes in both WebMvc.fn as well as
WebFlux.fn.

 - ServerRequest now exposes a RequestPath through requestPath(), and
   pathContainer() has been deprecated.

 - The PathPredicate and PathResourceLookupFunction now respects this
   RequestPath's pathInApplication() in their path-related
   functionality.

 - When nesting, the PathPredicate now appends the matched part of the
   path to the current context path, instead of removing the matched
   part (which was done previously). This has the same result: the
   matched part is gone, but now the full path stays the same.

Closes gh-25270

spring-test/src/main/java/org/springframework/mock/web/reactive/function/server/MockServerRequest.java

@@ -41,7 +41,6 @@
 import org.springframework.http.MediaType;
 import org.springframework.http.codec.HttpMessageReader;
 import org.springframework.http.codec.multipart.Part;
-import org.springframework.http.server.PathContainer;
 import org.springframework.http.server.RequestPath;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.lang.Nullable;
@@ -69,7 +68,7 @@ public final class MockServerRequest implements ServerRequest {
 
 	private final URI uri;
 
-	private final RequestPath pathContainer;
+	private final RequestPath requestPath;
 
 	private final MockHeaders headers;
 
@@ -88,7 +87,7 @@ public final class MockServerRequest implements ServerRequest {
 	private final WebSession session;
 
 	@Nullable
-	private Principal principal;
+	private final Principal principal;
 
 	@Nullable
 	private final InetSocketAddress remoteAddress;
@@ -111,7 +110,7 @@ private MockServerRequest(HttpMethod method, URI uri, String contextPath, MockHe
 
 		this.method = method;
 		this.uri = uri;
-		this.pathContainer = RequestPath.parse(uri, contextPath);
+		this.requestPath = RequestPath.parse(uri, contextPath);
 		this.headers = headers;
 		this.cookies = cookies;
 		this.body = body;
@@ -148,8 +147,8 @@ public UriBuilder uriBuilder() {
 	}
 
 	@Override
-	public PathContainer pathContainer() {
-		return this.pathContainer;
+	public RequestPath requestPath() {
+		return this.requestPath;
 	}
 
 	@Override

spring-web/src/main/java/org/springframework/web/util/pattern/PathPattern.java

@@ -249,7 +249,7 @@ else if (!hasLength(pathContainer)) {
 	@Nullable
 	public PathRemainingMatchInfo matchStartOfPath(PathContainer pathContainer) {
 		if (this.head == null) {
-			return new PathRemainingMatchInfo(pathContainer);
+			return new PathRemainingMatchInfo(EMPTY_PATH, pathContainer);
 		}
 		else if (!hasLength(pathContainer)) {
 			return null;
@@ -262,15 +262,17 @@ else if (!hasLength(pathContainer)) {
 			return null;
 		}
 		else {
-			PathRemainingMatchInfo info;
+			PathContainer pathMatched;
+			PathContainer pathRemaining;
 			if (matchingContext.remainingPathIndex == pathContainer.elements().size()) {
-				info = new PathRemainingMatchInfo(EMPTY_PATH, matchingContext.getPathMatchResult());
+				pathMatched = pathContainer;
+				pathRemaining = EMPTY_PATH;
 			}
 			else {
-				info = new PathRemainingMatchInfo(pathContainer.subPath(matchingContext.remainingPathIndex),
-						matchingContext.getPathMatchResult());
+				pathMatched = pathContainer.subPath(0, matchingContext.remainingPathIndex);
+				pathRemaining = pathContainer.subPath(matchingContext.remainingPathIndex);
 			}
-			return info;
+			return new PathRemainingMatchInfo(pathMatched, pathRemaining, matchingContext.getPathMatchResult());
 		}
 	}
 
@@ -592,20 +594,32 @@ public String toString() {
 	 */
 	public static class PathRemainingMatchInfo {
 
+		private final PathContainer pathMatched;
+
 		private final PathContainer pathRemaining;
 
 		private final PathMatchInfo pathMatchInfo;
 
 
-		PathRemainingMatchInfo(PathContainer pathRemaining) {
-			this(pathRemaining, PathMatchInfo.EMPTY);
+		PathRemainingMatchInfo(PathContainer pathMatched, PathContainer pathRemaining) {
+			this(pathMatched, pathRemaining, PathMatchInfo.EMPTY);
 		}
 
-		PathRemainingMatchInfo(PathContainer pathRemaining, PathMatchInfo pathMatchInfo) {
+		PathRemainingMatchInfo(PathContainer pathMatched, PathContainer pathRemaining,
+				PathMatchInfo pathMatchInfo) {
 			this.pathRemaining = pathRemaining;
+			this.pathMatched = pathMatched;
 			this.pathMatchInfo = pathMatchInfo;
 		}
 
+		/**
+		 * Return the part of a path that was matched by a pattern.
+		 * @since 5.3
+		 */
+		public PathContainer getPathMatched() {
+			return this.pathMatched;
+		}
+
 		/**
 		 * Return the part of a path that was not matched by a pattern.
 		 */

spring-web/src/test/java/org/springframework/web/util/pattern/PathPatternTests.java

@@ -557,18 +557,21 @@ public void pathRemainingEnhancements_spr15419() {
 		pp = parse("/{this}/{one}/{here}");
 		pri = getPathRemaining(pp, "/foo/bar/goo/boo");
 		assertThat(pri.getPathRemaining().value()).isEqualTo("/boo");
+		assertThat(pri.getPathMatched().value()).isEqualTo("/foo/bar/goo");
 		assertThat(pri.getUriVariables().get("this")).isEqualTo("foo");
 		assertThat(pri.getUriVariables().get("one")).isEqualTo("bar");
 		assertThat(pri.getUriVariables().get("here")).isEqualTo("goo");
 
 		pp = parse("/aaa/{foo}");
 		pri = getPathRemaining(pp, "/aaa/bbb");
 		assertThat(pri.getPathRemaining().value()).isEqualTo("");
+		assertThat(pri.getPathMatched().value()).isEqualTo("/aaa/bbb");
 		assertThat(pri.getUriVariables().get("foo")).isEqualTo("bbb");
 
 		pp = parse("/aaa/bbb");
 		pri = getPathRemaining(pp, "/aaa/bbb");
 		assertThat(pri.getPathRemaining().value()).isEqualTo("");
+		assertThat(pri.getPathMatched().value()).isEqualTo("/aaa/bbb");
 		assertThat(pri.getUriVariables().size()).isEqualTo(0);
 
 		pp = parse("/*/{foo}/b*");

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/DefaultServerRequest.java

@@ -43,7 +43,7 @@
 import org.springframework.http.MediaType;
 import org.springframework.http.codec.HttpMessageReader;
 import org.springframework.http.codec.multipart.Part;
-import org.springframework.http.server.PathContainer;
+import org.springframework.http.server.RequestPath;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.http.server.reactive.ServerHttpResponse;
 import org.springframework.lang.Nullable;
@@ -123,7 +123,7 @@ public UriBuilder uriBuilder() {
 	}
 
 	@Override
-	public PathContainer pathContainer() {
+	public RequestPath requestPath() {
 		return request().getPath();
 	}
 

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/PathResourceLookupFunction.java

@@ -56,7 +56,7 @@ public PathResourceLookupFunction(String pattern, Resource location) {
 
 	@Override
 	public Mono<Resource> apply(ServerRequest request) {
-		PathContainer pathContainer = request.pathContainer();
+		PathContainer pathContainer = request.requestPath().pathWithinApplication();
 		if (!this.pattern.matches(pathContainer)) {
 			return Mono.empty();
 		}

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/RequestPredicates.java

@@ -19,7 +19,6 @@
 import java.net.InetSocketAddress;
 import java.net.URI;
 import java.security.Principal;
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.EnumSet;
@@ -47,6 +46,7 @@
 import org.springframework.http.codec.HttpMessageReader;
 import org.springframework.http.codec.multipart.Part;
 import org.springframework.http.server.PathContainer;
+import org.springframework.http.server.RequestPath;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.lang.NonNull;
 import org.springframework.lang.Nullable;
@@ -492,7 +492,7 @@ public PathPatternPredicate(PathPattern pattern) {
 
 		@Override
 		public boolean test(ServerRequest request) {
-			PathContainer pathContainer = request.pathContainer();
+			PathContainer pathContainer = request.requestPath().pathWithinApplication();
 			PathPattern.PathMatchInfo info = this.pattern.matchAndExtract(pathContainer);
 			traceMatch("Pattern", this.pattern.getPatternString(), request.path(), info != null);
 			if (info != null) {
@@ -518,7 +518,7 @@ private static void mergeAttributes(ServerRequest request, Map<String, String> v
 
 		@Override
 		public Optional<ServerRequest> nest(ServerRequest request) {
-			return Optional.ofNullable(this.pattern.matchStartOfPath(request.pathContainer()))
+			return Optional.ofNullable(this.pattern.matchStartOfPath(request.requestPath().pathWithinApplication()))
 					.map(info -> new SubPathServerRequestWrapper(request, info, this.pattern));
 		}
 
@@ -926,17 +926,27 @@ private static class SubPathServerRequestWrapper implements ServerRequest {
 
 		private final ServerRequest request;
 
-		private final PathContainer pathContainer;
+		private final RequestPath requestPath;
 
 		private final Map<String, Object> attributes;
 
 		public SubPathServerRequestWrapper(ServerRequest request,
 				PathPattern.PathRemainingMatchInfo info, PathPattern pattern) {
 			this.request = request;
-			this.pathContainer = new SubPathContainer(info.getPathRemaining());
+			this.requestPath = requestPath(request.requestPath(), info);
 			this.attributes = mergeAttributes(request, info.getUriVariables(), pattern);
 		}
 
+		private static RequestPath requestPath(RequestPath original, PathPattern.PathRemainingMatchInfo info) {
+			StringBuilder contextPath = new StringBuilder(original.contextPath().value());
+			contextPath.append(info.getPathMatched().value());
+			int length = contextPath.length();
+			if (length > 0 && contextPath.charAt(length - 1) == '/') {
+				contextPath.setLength(length - 1);
+			}
+			return original.modifyContextPath(contextPath.toString());
+		}
+
 		private static Map<String, Object> mergeAttributes(ServerRequest request,
 		Map<String, String> pathVariables, PathPattern pattern) {
 			Map<String, Object> result = new ConcurrentHashMap<>(request.attributes());
@@ -972,13 +982,8 @@ public UriBuilder uriBuilder() {
 		}
 
 		@Override
-		public String path() {
-			return this.pathContainer.value();
-		}
-
-		@Override
-		public PathContainer pathContainer() {
-			return this.pathContainer;
+		public RequestPath requestPath() {
+			return this.requestPath;
 		}
 
 		@Override
@@ -1089,46 +1094,6 @@ public String toString() {
 			return method() + " " +  path();
 		}
 
-		private static class SubPathContainer implements PathContainer {
-
-			private static final PathContainer.Separator SEPARATOR = () -> "/";
-
-
-			private final String value;
-
-			private final List<Element> elements;
-
-			public SubPathContainer(PathContainer original) {
-				this.value = prefixWithSlash(original.value());
-				this.elements = prependWithSeparator(original.elements());
-			}
-
-			private static String prefixWithSlash(String path) {
-				if (!path.startsWith("/")) {
-					path = "/" + path;
-				}
-				return path;
-			}
-
-			private static List<Element> prependWithSeparator(List<Element> elements) {
-				List<Element> result = new ArrayList<>(elements);
-				if (result.isEmpty() || !(result.get(0) instanceof Separator)) {
-					result.add(0, SEPARATOR);
-				}
-				return Collections.unmodifiableList(result);
-			}
-
-
-			@Override
-			public String value() {
-				return this.value;
-			}
-
-			@Override
-			public List<Element> elements() {
-				return this.elements;
-			}
-		}
 	}
 
 }

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/ServerRequest.java

@@ -42,6 +42,7 @@
 import org.springframework.http.codec.json.Jackson2CodecSupport;
 import org.springframework.http.codec.multipart.Part;
 import org.springframework.http.server.PathContainer;
+import org.springframework.http.server.RequestPath;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
@@ -100,14 +101,24 @@ default HttpMethod method() {
 	 * Get the request path.
 	 */
 	default String path() {
-		return uri().getRawPath();
+		return requestPath().pathWithinApplication().value();
 	}
 
 	/**
 	 * Get the request path as a {@code PathContainer}.
+	 * @deprecated as of 5.3, in favor on {@link #requestPath()}
 	 */
+	@Deprecated
 	default PathContainer pathContainer() {
-		return PathContainer.parsePath(path());
+		return requestPath();
+	}
+
+	/**
+	 * Get the request path as a {@code PathContainer}.
+	 * @since 5.3
+	 */
+	default RequestPath requestPath() {
+		return exchange().getRequest().getPath();
 	}
 
 	/**

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/support/ServerRequestWrapper.java

@@ -38,6 +38,7 @@
 import org.springframework.http.codec.HttpMessageReader;
 import org.springframework.http.codec.multipart.Part;
 import org.springframework.http.server.PathContainer;
+import org.springframework.http.server.RequestPath;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.util.Assert;
 import org.springframework.util.MultiValueMap;
@@ -104,10 +105,16 @@ public String path() {
 	}
 
 	@Override
+	@Deprecated
 	public PathContainer pathContainer() {
 		return this.delegate.pathContainer();
 	}
 
+	@Override
+	public RequestPath requestPath() {
+		return this.delegate.requestPath();
+	}
+
 	@Override
 	public Headers headers() {
 		return this.delegate.headers();

spring-webflux/src/test/java/org/springframework/web/reactive/function/server/RequestPredicatesTests.java

@@ -29,7 +29,6 @@
 import org.springframework.web.testfixture.server.MockServerWebExchange;
 import org.springframework.web.util.pattern.PathPatternParser;
 
-import static java.util.Collections.emptyList;
 import static org.assertj.core.api.Assertions.assertThat;
 
 /**
@@ -141,7 +140,7 @@ public void path() {
 		URI uri = URI.create("https://localhost/path");
 		RequestPredicate predicate = RequestPredicates.path("/p*");
 		MockServerHttpRequest mockRequest = MockServerHttpRequest.get(uri.toString()).build();
-		ServerRequest request = new DefaultServerRequest(MockServerWebExchange.from(mockRequest), emptyList());
+		ServerRequest request = new DefaultServerRequest(MockServerWebExchange.from(mockRequest), Collections.emptyList());
 		assertThat(predicate.test(request)).isTrue();
 
 		mockRequest = MockServerHttpRequest.head("https://example.com").build();
@@ -178,6 +177,15 @@ public void pathPredicates() {
 		assertThat(predicate.test(request)).isTrue();
 	}
 
+	@Test
+	public void pathWithContext() {
+		RequestPredicate predicate = RequestPredicates.path("/p*");
+		MockServerHttpRequest mockRequest = MockServerHttpRequest.get("https://localhost/context/path")
+				.contextPath("/context").build();
+		ServerRequest request = new DefaultServerRequest(MockServerWebExchange.from(mockRequest), Collections.emptyList());
+		assertThat(predicate.test(request)).isTrue();
+	}
+
 	@Test
 	public void headers() {
 		String name = "MyHeader";