Add syntactic sugar for URI paths (gh-3293)

spring-cloud-gateway-server-webflux/src/main/java/org/springframework/cloud/gateway/route/RouteDefinitionRouteLocator.java

@@ -16,6 +16,7 @@
 
 package org.springframework.cloud.gateway.route;
 
+import java.net.URI;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
@@ -179,6 +180,42 @@ List<GatewayFilter> loadGatewayFilters(String id, List<FilterDefinition> filterD
 	}
 
 	private List<GatewayFilter> getFilters(RouteDefinition routeDefinition) {
+
+		// --- GH-3293: URI Path Syntactic Sugar ---
+		URI uri = routeDefinition.getUri();
+		if (uri != null && org.springframework.util.StringUtils.hasText(uri.getPath()) && !"/".equals(uri.getPath())) {
+
+			String path = uri.getPath();
+
+			// check if SetPath already exists to avoid duplication
+			boolean hasSetPath = routeDefinition.getFilters()
+				.stream()
+				.anyMatch(f -> "SetPath".equalsIgnoreCase(f.getName()));
+
+			if (!hasSetPath) {
+				// 1. Create the FilterDefinition programmatically
+				FilterDefinition sugar = new FilterDefinition();
+				sugar.setName("SetPath");
+				// SetPath expects a parameter named 'template'
+				sugar.addArg("template", path);
+
+				// Add it at the beginning of the filter chain
+				routeDefinition.getFilters().add(0, sugar);
+
+				// 2. Strip the path from the URI to prevent double-pathing
+				// (e.g., http://example.com/foo -> http://example.com)
+				URI strippedUri = org.springframework.web.util.UriComponentsBuilder.fromUri(uri)
+					.replacePath(null)
+					.build()
+					.toUri();
+				routeDefinition.setUri(strippedUri);
+			}
+		}
+		// --- END GH-3293 ---
+
+		// ... existing code follows (List<GatewayFilter> filters = new ArrayList<>();
+		// etc.)
+
 		List<GatewayFilter> filters = new ArrayList<>();
 		Objects.requireNonNull(routeDefinition.getId(), "Route id must be set");
 		// TODO: support option to apply defaults after route specific filters?

spring-cloud-gateway-server-webflux/src/test/java/org/springframework/cloud/gateway/route/RouteDefinitionRouteLocatorTests.java

@@ -200,6 +200,41 @@ public void contextLoadsAndApplyRouteIdToRetryFilter() {
 		}).expectComplete().verify();
 	}
 
+	@Test
+	public void uriWithMappingShouldAddSetPathFilter() {
+		// 1. Setup
+		List<RoutePredicateFactory> predicates = Arrays.asList(new HostRoutePredicateFactory());
+		List<GatewayFilterFactory> gatewayFilterFactories = Arrays
+			.asList(new org.springframework.cloud.gateway.filter.factory.SetPathGatewayFilterFactory());
+
+		GatewayProperties gatewayProperties = new GatewayProperties();
+
+		// Standard way to create the definition
+		RouteDefinition definition = new RouteDefinition();
+		definition.setId("sugar_test");
+		definition.setUri(URI.create("https://example.com/foo/bar"));
+		definition.setPredicates(Arrays.asList(new PredicateDefinition("Host=*.example.com")));
+
+		gatewayProperties.setRoutes(Arrays.asList(definition));
+
+		PropertiesRouteDefinitionLocator routeDefinitionLocator = new PropertiesRouteDefinitionLocator(
+				gatewayProperties);
+
+		// 2. Initialize the Locator
+		RouteDefinitionRouteLocator routeDefinitionRouteLocator = new RouteDefinitionRouteLocator(
+				new CompositeRouteDefinitionLocator(Flux.just(routeDefinitionLocator)), predicates,
+				gatewayFilterFactories, gatewayProperties, new ConfigurationService(null, () -> null, () -> null));
+
+		// 3. Verify
+		StepVerifier.create(routeDefinitionRouteLocator.getRoutes()).assertNext(route -> {
+			assertThat(route.getUri().toString()).isEqualTo("https://example.com:443");
+
+			List<GatewayFilter> filters = route.getFilters();
+			assertThat(filters).hasSize(1);
+			assertThat(getFilterClassName(filters.get(0))).contains("SetPath");
+		}).expectComplete().verify();
+	}
+
 	private List<RouteDefinition> containsInvalidRoutes() {
 		RouteDefinition foo = new RouteDefinition();
 		foo.setId("foo");