Support setting Spring.webflux.base-path and supporting it in path predicate

docs/modules/ROOT/pages/spring-cloud-gateway/request-predicates-factories.adoc

@@ -192,6 +192,8 @@ This route matches if the request path was, for example: `/red/1` or `/red/1/` o
 
 If `matchTrailingSlash` is set to `false`, then request path `/red/1/` will not be matched.
 
+If you have set `spring.webflux.base-path` property, this will influence the path matching. The property value will be automatically prepended to the path patterns. For example, with `spring.webflux.base-path=/app` and a path pattern of `/red/{segment}`, the full pattern used for matching would be `/app/red/{segment}`.
+
 This predicate extracts the URI template variables (such as `segment`, defined in the preceding example) as a map of names and values and places it in the `ServerWebExchange.getAttributes()` with a key defined in `ServerWebExchangeUtils.URI_TEMPLATE_VARIABLES_ATTRIBUTE`.
 Those values are then available for use by <<gateway-route-filters,`GatewayFilter` factories>>
 

spring-cloud-gateway-server/src/main/java/org/springframework/cloud/gateway/config/GatewayAutoConfiguration.java

@@ -56,6 +56,7 @@
 import org.springframework.boot.autoconfigure.web.embedded.NettyWebServerFactoryCustomizer;
 import org.springframework.boot.autoconfigure.web.reactive.HttpHandlerAutoConfiguration;
 import org.springframework.boot.autoconfigure.web.reactive.WebFluxAutoConfiguration;
+import org.springframework.boot.autoconfigure.web.reactive.WebFluxProperties;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.boot.context.properties.PropertyMapper;
 import org.springframework.boot.ssl.SslBundles;
@@ -190,6 +191,7 @@
  * @author Mete Alpaslan Katırcıoğlu
  * @author Alberto C. Ríos
  * @author Olga Maciaszek-Sharma
+ * @author FuYiNan Guo
  */
 @Configuration(proxyBeanMethods = false)
 @ConditionalOnProperty(name = "spring.cloud.gateway.enabled", matchIfMissing = true)
@@ -471,8 +473,8 @@ public MethodRoutePredicateFactory methodRoutePredicateFactory() {
 
 	@Bean
 	@ConditionalOnEnabledPredicate
-	public PathRoutePredicateFactory pathRoutePredicateFactory() {
-		return new PathRoutePredicateFactory();
+	public PathRoutePredicateFactory pathRoutePredicateFactory(WebFluxProperties webFluxProperties) {
+		return new PathRoutePredicateFactory(webFluxProperties);
 	}
 
 	@Bean

spring-cloud-gateway-server/src/main/java/org/springframework/cloud/gateway/handler/predicate/PathRoutePredicateFactory.java

@@ -24,8 +24,10 @@
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+import org.springframework.boot.autoconfigure.web.reactive.WebFluxProperties;
 import org.springframework.core.style.ToStringCreator;
 import org.springframework.http.server.PathContainer;
+import org.springframework.util.StringUtils;
 import org.springframework.web.server.ServerWebExchange;
 import org.springframework.web.util.pattern.PathPattern;
 import org.springframework.web.util.pattern.PathPattern.PathMatchInfo;
@@ -41,6 +43,7 @@
 /**
  * @author Spencer Gibb
  * @author Dhawal Kapil
+ * @author FuYiNan Guo
  */
 public class PathRoutePredicateFactory extends AbstractRoutePredicateFactory<PathRoutePredicateFactory.Config> {
 
@@ -50,8 +53,20 @@ public class PathRoutePredicateFactory extends AbstractRoutePredicateFactory<Pat
 
 	private PathPatternParser pathPatternParser = new PathPatternParser();
 
+	private final WebFluxProperties webFluxProperties;
+
+	/**
+	 * @deprecated {@link #PathRoutePredicateFactory(WebFluxProperties)}
+	 */
+	@Deprecated
 	public PathRoutePredicateFactory() {
 		super(Config.class);
+		this.webFluxProperties = new WebFluxProperties();
+	}
+
+	public PathRoutePredicateFactory(WebFluxProperties webFluxProperties) {
+		super(Config.class);
+		this.webFluxProperties = webFluxProperties;
 	}
 
 	private static void traceMatch(String prefix, Object desired, Object actual, boolean match) {
@@ -82,7 +97,16 @@ public Predicate<ServerWebExchange> apply(Config config) {
 		synchronized (this.pathPatternParser) {
 			pathPatternParser.setMatchOptionalTrailingSeparator(config.isMatchTrailingSlash());
 			config.getPatterns().forEach(pattern -> {
-				PathPattern pathPattern = this.pathPatternParser.parse(pattern);
+				String basePath = webFluxProperties.getBasePath();
+				boolean basePathIsNotBlank = StringUtils.hasText(basePath);
+				String pathPatternStr = pattern;
+				if (basePathIsNotBlank) {
+					if (pattern.length() > 1 && !pattern.startsWith("/")) {
+						basePath += ("/");
+					}
+					pathPatternStr = basePath + pattern;
+				}
+				PathPattern pathPattern = this.pathPatternParser.parse(pathPatternStr);
 				pathPatterns.add(pathPattern);
 			});
 		}

spring-cloud-gateway-server/src/test/java/org/springframework/cloud/gateway/handler/predicate/GatewayPredicateVisitorTests.java

@@ -16,25 +16,41 @@
 
 package org.springframework.cloud.gateway.handler.predicate;
 
+import java.net.URI;
 import java.util.ArrayList;
+import java.util.LinkedHashSet;
+import java.util.List;
 import java.util.function.Predicate;
 
 import org.junit.jupiter.api.Test;
+import org.mockito.ArgumentCaptor;
+import reactor.core.publisher.Mono;
 
+import org.springframework.boot.autoconfigure.web.reactive.WebFluxProperties;
+import org.springframework.cloud.gateway.filter.GatewayFilter;
+import org.springframework.cloud.gateway.filter.GatewayFilterChain;
+import org.springframework.cloud.gateway.filter.factory.StripPrefixGatewayFilterFactory;
 import org.springframework.cloud.gateway.handler.AsyncPredicate;
 import org.springframework.cloud.gateway.route.Route;
+import org.springframework.mock.http.server.reactive.MockServerHttpRequest;
+import org.springframework.mock.web.server.MockServerWebExchange;
 import org.springframework.web.server.ServerWebExchange;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.GATEWAY_ORIGINAL_REQUEST_URL_ATTR;
+import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR;
 
 /**
  * @author Spencer Gibb
+ * @author FuYiNan Guo
  */
 public class GatewayPredicateVisitorTests {
 
 	@Test
 	public void asyncPredicateVisitVisitsEachNode() {
-		PathRoutePredicateFactory pathRoutePredicateFactory = new PathRoutePredicateFactory();
+		PathRoutePredicateFactory pathRoutePredicateFactory = new PathRoutePredicateFactory(new WebFluxProperties());
 		HostRoutePredicateFactory hostRoutePredicateFactory = new HostRoutePredicateFactory();
 		ReadBodyRoutePredicateFactory readBodyRoutePredicateFactory1 = new ReadBodyRoutePredicateFactory();
 		ReadBodyRoutePredicateFactory readBodyRoutePredicateFactory2 = new ReadBodyRoutePredicateFactory();
@@ -55,7 +71,7 @@ public void asyncPredicateVisitVisitsEachNode() {
 
 	@Test
 	public void predicateVisitVisitsEachNode() {
-		PathRoutePredicateFactory pathRoutePredicateFactory = new PathRoutePredicateFactory();
+		PathRoutePredicateFactory pathRoutePredicateFactory = new PathRoutePredicateFactory(new WebFluxProperties());
 		HostRoutePredicateFactory hostRoutePredicateFactory = new HostRoutePredicateFactory();
 		Predicate<ServerWebExchange> predicate = pathRoutePredicateFactory.apply(pathRoutePredicateFactory.newConfig())
 			.and(hostRoutePredicateFactory.apply(hostRoutePredicateFactory.newConfig()));
@@ -68,4 +84,59 @@ public void predicateVisitVisitsEachNode() {
 			.hasExactlyElementsOfTypes(PathRoutePredicateFactory.Config.class, HostRoutePredicateFactory.Config.class);
 	}
 
+	@Test
+	public void pathRoutePredicateVisitWithSetWebfluxBasePath() {
+		WebFluxProperties webFluxProperties = new WebFluxProperties();
+		webFluxProperties.setBasePath("/gw/api/v1");
+
+		PathRoutePredicateFactory pathRoutePredicateFactory = new PathRoutePredicateFactory(webFluxProperties);
+		PathRoutePredicateFactory.Config config = new PathRoutePredicateFactory.Config()
+				.setPatterns(List.of("/temp/**"))
+				.setMatchTrailingSlash(true);
+
+		Predicate<ServerWebExchange> predicate = pathRoutePredicateFactory.apply(config);
+
+		ServerWebExchange exchange = MockServerWebExchange.from(MockServerHttpRequest.get("http://127.0.0.1:8080/gw/api/v1/temp/test")
+				.build());
+
+		assertThat(predicate.test(exchange)).isEqualTo(true);
+	}
+
+	@Test
+	public void pathRoutePredicateVisitWithSetWebfluxBasePathStripPrefix() {
+		WebFluxProperties webFluxProperties = new WebFluxProperties();
+		webFluxProperties.setBasePath("/gw/api/v1");
+
+		PathRoutePredicateFactory pathRoutePredicateFactory = new PathRoutePredicateFactory(webFluxProperties);
+		PathRoutePredicateFactory.Config config = new PathRoutePredicateFactory.Config()
+				.setPatterns(List.of("/temp/**"))
+				.setMatchTrailingSlash(true);
+
+		Predicate<ServerWebExchange> predicate = pathRoutePredicateFactory.apply(config);
+
+		ServerWebExchange exchange = MockServerWebExchange.from(MockServerHttpRequest.get("http://127.0.0.1:8080/gw/api/v1/temp/test")
+				.build());
+
+		assertThat(predicate.test(exchange)).isEqualTo(true);
+
+		// webflux base path strips prefix is 3
+		GatewayFilter filter = new StripPrefixGatewayFilterFactory().apply(c -> c.setParts(3));
+
+		GatewayFilterChain filterChain = mock(GatewayFilterChain.class);
+
+		ArgumentCaptor<ServerWebExchange> captor = ArgumentCaptor.forClass(ServerWebExchange.class);
+		when(filterChain.filter(captor.capture())).thenReturn(Mono.empty());
+
+		filter.filter(exchange, filterChain);
+
+		ServerWebExchange webExchange = captor.getValue();
+
+		assertThat(webExchange.getRequest().getURI()).hasPath("/temp/test");
+
+		URI requestUrl = webExchange.getRequiredAttribute(GATEWAY_REQUEST_URL_ATTR);
+		assertThat(requestUrl).hasScheme("http").hasHost("127.0.0.1").hasPort(8080).hasPath("/temp/test");
+
+		LinkedHashSet<URI> uris = webExchange.getRequiredAttribute(GATEWAY_ORIGINAL_REQUEST_URL_ATTR);
+		assertThat(uris).contains(exchange.getRequest().getURI());
+	}
 }

spring-cloud-gateway-server/src/test/java/org/springframework/cloud/gateway/handler/predicate/PathRoutePredicateFactoryTests.java

@@ -26,6 +26,7 @@
 import org.springframework.beans.factory.config.BeanPostProcessor;
 import org.springframework.boot.SpringBootConfiguration;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.autoconfigure.web.reactive.WebFluxProperties;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.cloud.gateway.handler.RoutePredicateHandlerMapping;
 import org.springframework.cloud.gateway.handler.predicate.PathRoutePredicateFactory.Config;
@@ -133,14 +134,14 @@ public void matchOptionalTrailingSeparatorCopiedToMatchTrailingSlash() {
 	@Test
 	public void toStringFormat() {
 		Config config = new Config().setPatterns(Arrays.asList("patternA", "patternB")).setMatchTrailingSlash(false);
-		Predicate predicate = new PathRoutePredicateFactory().apply(config);
+		Predicate predicate = new PathRoutePredicateFactory(new WebFluxProperties()).apply(config);
 		assertThat(predicate.toString()).contains("patternA").contains("patternB").contains("false");
 	}
 
 	@Test
 	public void toStringFormatMatchTrailingSlashTrue() {
 		Config config = new Config().setPatterns(Arrays.asList("patternA", "patternB")).setMatchTrailingSlash(true);
-		Predicate<ServerWebExchange> predicate = new PathRoutePredicateFactory().apply(config);
+		Predicate<ServerWebExchange> predicate = new PathRoutePredicateFactory(new WebFluxProperties()).apply(config);
 		assertThat(predicate.toString()).contains("patternA").contains("patternB").contains("true");
 	}
 

spring-cloud-gateway-server/src/test/java/org/springframework/cloud/gateway/handler/predicate/PathRoutePredicatePathContainerAttrBenchMarkTests.java

@@ -30,6 +30,7 @@
 import org.openjdk.jmh.annotations.Threads;
 import org.openjdk.jmh.annotations.Warmup;
 
+import org.springframework.boot.autoconfigure.web.reactive.WebFluxProperties;
 import org.springframework.mock.http.server.reactive.MockServerHttpRequest;
 import org.springframework.mock.web.server.MockServerWebExchange;
 import org.springframework.web.server.ServerWebExchange;
@@ -54,7 +55,7 @@ public class PathRoutePredicatePathContainerAttrBenchMarkTests {
 			PathRoutePredicateFactory.Config config = new PathRoutePredicateFactory.Config()
 				.setPatterns(Collections.singletonList(PATH_PATTERN_PREFIX + i))
 				.setMatchTrailingSlash(true);
-			Predicate<ServerWebExchange> predicate = new PathRoutePredicateFactory().apply(config);
+			Predicate<ServerWebExchange> predicate = new PathRoutePredicateFactory(new WebFluxProperties()).apply(config);
 			predicates.add(predicate);
 		}
 	}

spring-cloud-gateway-server/src/test/java/org/springframework/cloud/gateway/support/tagsprovider/GatewayPathTagsProviderTests.java

@@ -22,6 +22,7 @@
 import io.micrometer.core.instrument.Tags;
 import org.junit.jupiter.api.Test;
 
+import org.springframework.boot.autoconfigure.web.reactive.WebFluxProperties;
 import org.springframework.cloud.gateway.handler.predicate.HostRoutePredicateFactory;
 import org.springframework.cloud.gateway.handler.predicate.MethodRoutePredicateFactory;
 import org.springframework.cloud.gateway.handler.predicate.PathRoutePredicateFactory;
@@ -56,7 +57,7 @@ void addPathToRoutes() {
 		Route route = Route.async()
 			.id("git")
 			.uri(ROUTE_URI)
-			.predicate(new PathRoutePredicateFactory().apply(pathConfig)
+			.predicate(new PathRoutePredicateFactory(new WebFluxProperties()).apply(pathConfig)
 				.and(new HostRoutePredicateFactory().apply(hostConfig)))
 			.build();
 
@@ -81,8 +82,8 @@ void addsMultiplePathToRoutes() {
 		Route route = Route.async()
 			.id("git")
 			.uri(ROUTE_URI)
-			.predicate(new PathRoutePredicateFactory().apply(pathConfig)
-				.or(new PathRoutePredicateFactory().apply(pathConfig2)))
+			.predicate(new PathRoutePredicateFactory(new WebFluxProperties()).apply(pathConfig)
+				.or(new PathRoutePredicateFactory(new WebFluxProperties()).apply(pathConfig2)))
 			.build();
 
 		ServerWebExchange exchange = MockServerWebExchange.from(MockServerHttpRequest.get(ROUTE_URI).build());