Fix request mapping of endpoint path-mapped to /

Closes gh-35426

Author: wilkinsona

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/security/reactive/EndpointRequestTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -235,6 +235,24 @@ void toStringWhenIncludedExcludedEndpoints() {
 		assertThat(matcher).hasToString("EndpointRequestMatcher includes=[*], excludes=[bar], includeLinks=false");
 	}
 
+	@Test
+	void toAnyEndpointWhenEndpointPathMappedToRootIsExcludedShouldNotMatchRoot() {
+		ServerWebExchangeMatcher matcher = EndpointRequest.toAnyEndpoint().excluding("root");
+		RequestMatcherAssert assertMatcher = assertMatcher(matcher, new PathMappedEndpoints("/", () -> List
+			.of(mockEndpoint(EndpointId.of("root"), "/"), mockEndpoint(EndpointId.of("alpha"), "alpha"))));
+		assertMatcher.doesNotMatch("/");
+		assertMatcher.matches("/alpha");
+		assertMatcher.matches("/alpha/sub");
+	}
+
+	@Test
+	void toEndpointWhenEndpointPathMappedToRootShouldMatchRoot() {
+		ServerWebExchangeMatcher matcher = EndpointRequest.to("root");
+		RequestMatcherAssert assertMatcher = assertMatcher(matcher,
+				new PathMappedEndpoints("/", () -> List.of(mockEndpoint(EndpointId.of("root"), "/"))));
+		assertMatcher.matches("/");
+	}
+
 	private RequestMatcherAssert assertMatcher(ServerWebExchangeMatcher matcher) {
 		return assertMatcher(matcher, mockPathMappedEndpoints("/actuator"));
 	}

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/security/servlet/EndpointRequestTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -24,6 +24,7 @@
 import org.junit.jupiter.api.Test;
 
 import org.springframework.boot.actuate.autoconfigure.endpoint.web.WebEndpointProperties;
+import org.springframework.boot.actuate.autoconfigure.security.servlet.EndpointRequest.EndpointRequestMatcher;
 import org.springframework.boot.actuate.endpoint.EndpointId;
 import org.springframework.boot.actuate.endpoint.ExposableEndpoint;
 import org.springframework.boot.actuate.endpoint.Operation;
@@ -239,6 +240,24 @@ void toStringWhenIncludedExcludedEndpoints() {
 		assertThat(matcher).hasToString("EndpointRequestMatcher includes=[*], excludes=[bar], includeLinks=false");
 	}
 
+	@Test
+	void toAnyEndpointWhenEndpointPathMappedToRootIsExcludedShouldNotMatchRoot() {
+		EndpointRequestMatcher matcher = EndpointRequest.toAnyEndpoint().excluding("root");
+		RequestMatcherAssert assertMatcher = assertMatcher(matcher, new PathMappedEndpoints("", () -> List
+			.of(mockEndpoint(EndpointId.of("root"), "/"), mockEndpoint(EndpointId.of("alpha"), "alpha"))));
+		assertMatcher.doesNotMatch("/");
+		assertMatcher.matches("/alpha");
+		assertMatcher.matches("/alpha/sub");
+	}
+
+	@Test
+	void toEndpointWhenEndpointPathMappedToRootShouldMatchRoot() {
+		EndpointRequestMatcher matcher = EndpointRequest.to("root");
+		RequestMatcherAssert assertMatcher = assertMatcher(matcher,
+				new PathMappedEndpoints("", () -> List.of(mockEndpoint(EndpointId.of("root"), "/"))));
+		assertMatcher.matches("/");
+	}
+
 	private RequestMatcherAssert assertMatcher(RequestMatcher matcher) {
 		return assertMatcher(matcher, mockPathMappedEndpoints("/actuator"));
 	}

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/web/PathMappedEndpoints.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2022 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -140,7 +140,17 @@ public Iterator<PathMappedEndpoint> iterator() {
 	}
 
 	private String getPath(PathMappedEndpoint endpoint) {
-		return (endpoint != null) ? this.basePath + "/" + endpoint.getRootPath() : null;
+		if (endpoint == null) {
+			return null;
+		}
+		StringBuilder path = new StringBuilder(this.basePath);
+		if (!this.basePath.equals("/")) {
+			path.append("/");
+		}
+		if (!endpoint.getRootPath().equals("/")) {
+			path.append(endpoint.getRootPath());
+		}
+		return path.toString();
 	}
 
 }

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/web/annotation/RequestPredicateFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -86,7 +86,7 @@ private String getPath(String rootPath, OperationParameter[] selectorParameters,
 			boolean matchRemainingPathSegments) {
 		StringBuilder path = new StringBuilder(rootPath);
 		for (int i = 0; i < selectorParameters.length; i++) {
-			path.append("/{");
+			path.append((i != 0 || !rootPath.endsWith("/")) ? "/{" : "{");
 			if (i == selectorParameters.length - 1 && matchRemainingPathSegments) {
 				path.append("*");
 			}

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/web/reactive/AbstractWebFluxEndpointHandlerMapping.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -19,8 +19,10 @@
 import java.lang.reflect.Method;
 import java.nio.charset.StandardCharsets;
 import java.security.Principal;
+import java.util.ArrayList;
 import java.util.Collection;
 import java.util.LinkedHashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.function.Supplier;
 
@@ -176,10 +178,19 @@ protected ReactiveWebOperation wrapReactiveWebOperation(ExposableWebEndpoint end
 	private RequestMappingInfo createRequestMappingInfo(WebOperation operation) {
 		WebOperationRequestPredicate predicate = operation.getRequestPredicate();
 		String path = this.endpointMapping.createSubPath(predicate.getPath());
+		List<String> paths = new ArrayList<>();
+		paths.add(path);
+		if (!StringUtils.hasText(path)) {
+			paths.add("/");
+		}
 		RequestMethod method = RequestMethod.valueOf(predicate.getHttpMethod().name());
 		String[] consumes = StringUtils.toStringArray(predicate.getConsumes());
 		String[] produces = StringUtils.toStringArray(predicate.getProduces());
-		return RequestMappingInfo.paths(path).methods(method).consumes(consumes).produces(produces).build();
+		return RequestMappingInfo.paths(paths.toArray(new String[0]))
+			.methods(method)
+			.consumes(consumes)
+			.produces(produces)
+			.build();
 	}
 
 	private void registerLinksMapping() {

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/web/servlet/AbstractWebMvcEndpointHandlerMapping.java

@@ -196,7 +196,13 @@ protected ServletWebOperation wrapServletWebOperation(ExposableWebEndpoint endpo
 	}
 
 	private RequestMappingInfo createRequestMappingInfo(WebOperationRequestPredicate predicate, String path) {
-		return RequestMappingInfo.paths(this.endpointMapping.createSubPath(path))
+		String subPath = this.endpointMapping.createSubPath(path);
+		List<String> paths = new ArrayList<>();
+		paths.add(subPath);
+		if (!StringUtils.hasLength(subPath)) {
+			paths.add("/");
+		}
+		return RequestMappingInfo.paths(paths.toArray(new String[0]))
 			.options(this.builderConfig)
 			.methods(RequestMethod.valueOf(predicate.getHttpMethod().name()))
 			.consumes(predicate.getConsumes().toArray(new String[0]))

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/web/PathMappedEndpointsTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -91,6 +91,20 @@ void getPathWhenMissingIdShouldReturnNull() {
 		assertThat(mapped.getPath(EndpointId.of("xx"))).isNull();
 	}
 
+	@Test
+	void getPathWhenBasePathIsRootAndEndpointIsPathMappedToRootShouldReturnSingleSlash() {
+		PathMappedEndpoints mapped = new PathMappedEndpoints("/",
+				() -> List.of(mockEndpoint(EndpointId.of("root"), "/")));
+		assertThat(mapped.getPath(EndpointId.of("root"))).isEqualTo("/");
+	}
+
+	@Test
+	void getPathWhenBasePathIsRootAndEndpointIsPathMapped() {
+		PathMappedEndpoints mapped = new PathMappedEndpoints("/",
+				() -> List.of(mockEndpoint(EndpointId.of("a"), "alpha")));
+		assertThat(mapped.getPath(EndpointId.of("a"))).isEqualTo("/alpha");
+	}
+
 	@Test
 	void getAllRootPathsShouldReturnAllPaths() {
 		PathMappedEndpoints mapped = createTestMapped(null);

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/web/annotation/AbstractWebEndpointIntegrationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -38,6 +38,7 @@
 import org.springframework.boot.actuate.endpoint.annotation.Selector;
 import org.springframework.boot.actuate.endpoint.annotation.Selector.Match;
 import org.springframework.boot.actuate.endpoint.annotation.WriteOperation;
+import org.springframework.boot.actuate.endpoint.web.PathMapper;
 import org.springframework.boot.actuate.endpoint.web.WebEndpointResponse;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ConfigurableApplicationContext;
@@ -108,6 +109,21 @@ void readOperationWithEndpointsMappedToTheRoot() {
 					.isEqualTo(true));
 	}
 
+	@Test
+	void readOperationWithEndpointPathMappedToTheRoot() {
+		load(EndpointPathMappedToRootConfiguration.class, "", (client) -> {
+			client.get().uri("/").exchange().expectStatus().isOk().expectBody().jsonPath("All").isEqualTo(true);
+			client.get()
+				.uri("/some-part")
+				.exchange()
+				.expectStatus()
+				.isOk()
+				.expectBody()
+				.jsonPath("part")
+				.isEqualTo("some-part");
+		});
+	}
+
 	@Test
 	void readOperationWithSelector() {
 		load(TestEndpointConfiguration.class,
@@ -672,6 +688,17 @@ public TestEndpoint testEndpoint(EndpointDelegate endpointDelegate) {
 
 	}
 
+	@Configuration(proxyBeanMethods = false)
+	@Import(TestEndpointConfiguration.class)
+	protected static class EndpointPathMappedToRootConfiguration {
+
+		@Bean
+		PathMapper pathMapper() {
+			return (endpointId) -> "/";
+		}
+
+	}
+
 	@Configuration(proxyBeanMethods = false)
 	@Import(BaseConfiguration.class)
 	static class MatchAllRemainingEndpointConfiguration {

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/web/annotation/BaseConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -20,9 +20,11 @@
 import java.util.Collections;
 import java.util.List;
 
+import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.boot.actuate.endpoint.invoke.ParameterValueMapper;
 import org.springframework.boot.actuate.endpoint.invoke.convert.ConversionServiceParameterValueMapper;
 import org.springframework.boot.actuate.endpoint.web.EndpointMediaTypes;
+import org.springframework.boot.actuate.endpoint.web.PathMapper;
 import org.springframework.boot.web.embedded.tomcat.TomcatEmbeddedWebappClassLoader;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;
@@ -62,11 +64,11 @@ EndpointMediaTypes endpointMediaTypes() {
 
 	@Bean
 	WebEndpointDiscoverer webEndpointDiscoverer(EndpointMediaTypes endpointMediaTypes,
-			ApplicationContext applicationContext) {
+			ApplicationContext applicationContext, ObjectProvider<PathMapper> pathMappers) {
 		ParameterValueMapper parameterMapper = new ConversionServiceParameterValueMapper(
 				DefaultConversionService.getSharedInstance());
-		return new WebEndpointDiscoverer(applicationContext, parameterMapper, endpointMediaTypes, null,
-				Collections.emptyList(), Collections.emptyList());
+		return new WebEndpointDiscoverer(applicationContext, parameterMapper, endpointMediaTypes,
+				pathMappers.orderedStream().toList(), Collections.emptyList(), Collections.emptyList());
 	}
 
 	@Bean

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/web/annotation/RequestPredicateFactoryTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -68,6 +68,13 @@ void getRequestPredicateReturnsPredicateWithPath() {
 		assertThat(requestPredicate.getPath()).isEqualTo("/root/{one}/{*two}");
 	}
 
+	@Test
+	void getRequestPredicateWithSlashRootReturnsPredicateWithPathWithoutDoubleSlash() {
+		DiscoveredOperationMethod operationMethod = getDiscoveredOperationMethod(ValidSelectors.class);
+		WebOperationRequestPredicate requestPredicate = this.factory.getRequestPredicate("/", operationMethod);
+		assertThat(requestPredicate.getPath()).isEqualTo("/{one}/{*two}");
+	}
+
 	private DiscoveredOperationMethod getDiscoveredOperationMethod(Class<?> source) {
 		Method method = source.getDeclaredMethods()[0];
 		AnnotationAttributes attributes = new AnnotationAttributes();