API versioning support for Spring WebFlux

Closes gh-34566

spring-webflux/src/main/java/org/springframework/web/reactive/accept/ApiVersionResolver.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2002-2025 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
+ *
+ *      https://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.accept;
+
+import org.jspecify.annotations.Nullable;
+
+import org.springframework.web.server.ServerWebExchange;
+
+/**
+ * Contract to extract the version from a request.
+ *
+ * @author Rossen Stoyanchev
+ * @since 7.0
+ */
+@FunctionalInterface
+public
+interface ApiVersionResolver {
+
+	/**
+	 * Resolve the version for the given exchange.
+	 * @param exchange the current exchange
+	 * @return the version value, or {@code null} if not found
+	 */
+	@Nullable String resolveVersion(ServerWebExchange exchange);
+
+}

spring-webflux/src/main/java/org/springframework/web/reactive/accept/ApiVersionStrategy.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright 2002-2025 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
+ *
+ *      https://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.accept;
+
+import org.jspecify.annotations.Nullable;
+
+import org.springframework.web.accept.InvalidApiVersionException;
+import org.springframework.web.accept.MissingApiVersionException;
+import org.springframework.web.server.ServerWebExchange;
+
+/**
+ * The main component that encapsulates configuration preferences and strategies
+ * to manage API versioning for an application.
+ *
+ * @author Rossen Stoyanchev
+ * @since 7.0
+ */
+public interface ApiVersionStrategy {
+
+	/**
+	 * Resolve the version value from a request, e.g. from a request header.
+	 * @param exchange the current exchange
+	 * @return the version, if present or {@code null}
+	 */
+	@Nullable
+	String resolveVersion(ServerWebExchange exchange);
+
+	/**
+	 * Parse the version of a request into an Object.
+	 * @param version the value to parse
+	 * @return an Object that represents the version
+	 */
+	Comparable<?> parseVersion(String version);
+
+	/**
+	 * Validate a request version, including required and supported version checks.
+	 * @param requestVersion the version to validate
+	 * @param exchange the exchange
+	 * @throws MissingApiVersionException if the version is required, but not specified
+	 * @throws InvalidApiVersionException if the version is not supported
+	 */
+	void validateVersion(@Nullable Comparable<?> requestVersion, ServerWebExchange exchange)
+			throws MissingApiVersionException, InvalidApiVersionException;
+
+	/**
+	 * Return a default version to use for requests that don't specify one.
+	 */
+	@Nullable Comparable<?> getDefaultVersion();
+
+}

spring-webflux/src/main/java/org/springframework/web/reactive/accept/DefaultApiVersionStrategy.java

@@ -0,0 +1,132 @@
+/*
+ * Copyright 2002-2025 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
+ *
+ *      https://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.accept;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+import java.util.TreeSet;
+
+import org.jspecify.annotations.Nullable;
+
+import org.springframework.util.Assert;
+import org.springframework.web.accept.ApiVersionParser;
+import org.springframework.web.accept.InvalidApiVersionException;
+import org.springframework.web.accept.MissingApiVersionException;
+import org.springframework.web.server.ServerWebExchange;
+
+/**
+ * Default implementation of {@link ApiVersionStrategy} that delegates to the
+ * configured version resolvers and version parser.
+ *
+ * @author Rossen Stoyanchev
+ * @since 7.0
+ */
+public class DefaultApiVersionStrategy implements ApiVersionStrategy {
+
+	private final List<ApiVersionResolver> versionResolvers;
+
+	private final ApiVersionParser<?> versionParser;
+
+	private final boolean versionRequired;
+
+	private final @Nullable Comparable<?> defaultVersion;
+
+	private final Set<Comparable<?>> supportedVersions = new TreeSet<>();
+
+
+	/**
+	 * Create an instance.
+	 * @param versionResolvers one or more resolvers to try; the first non-null
+	 * value returned by any resolver becomes the resolved used
+	 * @param versionParser parser for to raw version values
+	 * @param versionRequired whether a version is required; if a request
+	 * does not have a version, and a {@code defaultVersion} is not specified,
+	 * validation fails with {@link MissingApiVersionException}
+	 * @param defaultVersion a default version to assign to requests that
+	 * don't specify one
+	 */
+	public DefaultApiVersionStrategy(
+			List<ApiVersionResolver> versionResolvers, ApiVersionParser<?> versionParser,
+			boolean versionRequired, @Nullable String defaultVersion) {
+
+		Assert.notEmpty(versionResolvers, "At least one ApiVersionResolver is required");
+		Assert.notNull(versionParser, "ApiVersionParser is required");
+
+		this.versionResolvers = new ArrayList<>(versionResolvers);
+		this.versionParser = versionParser;
+		this.versionRequired = (versionRequired && defaultVersion == null);
+		this.defaultVersion = (defaultVersion != null ? versionParser.parseVersion(defaultVersion) : null);
+	}
+
+
+	@Override
+	public @Nullable Comparable<?> getDefaultVersion() {
+		return this.defaultVersion;
+	}
+
+	/**
+	 * Add to the list of known, supported versions to check against in
+	 * {@link ApiVersionStrategy#validateVersion}. Request versions that are not
+	 * in the supported result in {@link InvalidApiVersionException}
+	 * in {@link ApiVersionStrategy#validateVersion}.
+	 * @param versions the versions to add
+	 */
+	public void addSupportedVersion(String... versions) {
+		for (String version : versions) {
+			this.supportedVersions.add(parseVersion(version));
+		}
+	}
+
+	@Override
+	public @Nullable String resolveVersion(ServerWebExchange exchange) {
+		for (ApiVersionResolver resolver : this.versionResolvers) {
+			String version = resolver.resolveVersion(exchange);
+			if (version != null) {
+				return version;
+			}
+		}
+		return null;
+	}
+
+	@Override
+	public Comparable<?> parseVersion(String version) {
+		return this.versionParser.parseVersion(version);
+	}
+
+	public void validateVersion(@Nullable Comparable<?> requestVersion, ServerWebExchange exchange)
+			throws MissingApiVersionException, InvalidApiVersionException {
+
+		if (requestVersion == null) {
+			if (this.versionRequired) {
+				throw new MissingApiVersionException();
+			}
+			return;
+		}
+
+		if (!this.supportedVersions.contains(requestVersion)) {
+			throw new InvalidApiVersionException(requestVersion.toString());
+		}
+	}
+
+	@Override
+	public String toString() {
+		return "DefaultApiVersionStrategy[supportedVersions=" + this.supportedVersions +
+				", versionRequired=" + this.versionRequired + ", defaultVersion=" + this.defaultVersion + "]";
+	}
+
+}

spring-webflux/src/main/java/org/springframework/web/reactive/accept/PathApiVersionResolver.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright 2002-2025 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
+ *
+ *      https://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.accept;
+
+import org.jspecify.annotations.Nullable;
+
+import org.springframework.http.server.PathContainer;
+import org.springframework.util.Assert;
+import org.springframework.web.server.ServerWebExchange;
+
+/**
+ * {@link ApiVersionResolver} that extract the version from a path segment.
+ *
+ * @author Rossen Stoyanchev
+ * @since 7.0
+ */
+public class PathApiVersionResolver implements ApiVersionResolver {
+
+	private final int pathSegmentIndex;
+
+
+	/**
+	 * Create a resolver instance.
+	 * @param pathSegmentIndex the index of the path segment that contains
+	 * the API version
+	 */
+	public PathApiVersionResolver(int pathSegmentIndex) {
+		Assert.isTrue(pathSegmentIndex >= 0, "'pathSegmentIndex' must be >= 0");
+		this.pathSegmentIndex = pathSegmentIndex;
+	}
+
+
+	@Override
+	public @Nullable String resolveVersion(ServerWebExchange exchange) {
+		int i = 0;
+		for (PathContainer.Element e : exchange.getRequest().getPath().pathWithinApplication().elements()) {
+			if (e instanceof PathContainer.PathSegment && i++ == this.pathSegmentIndex) {
+				return e.value();
+			}
+		}
+		return null;
+	}
+
+}

spring-webflux/src/main/java/org/springframework/web/reactive/config/ApiVersionConfigurer.java

@@ -0,0 +1,156 @@
+/*
+ * Copyright 2002-2025 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
+ *
+ *      https://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.config;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Set;
+
+import org.jspecify.annotations.Nullable;
+
+import org.springframework.web.accept.ApiVersionParser;
+import org.springframework.web.accept.SemanticApiVersionParser;
+import org.springframework.web.reactive.accept.ApiVersionResolver;
+import org.springframework.web.reactive.accept.ApiVersionStrategy;
+import org.springframework.web.reactive.accept.DefaultApiVersionStrategy;
+import org.springframework.web.reactive.accept.PathApiVersionResolver;
+
+/**
+ * Configure API versioning.
+ *
+ * @author Rossen Stoyanchev
+ * @since 7.0
+ */
+public class ApiVersionConfigurer {
+
+	private final List<ApiVersionResolver> versionResolvers = new ArrayList<>();
+
+	private @Nullable ApiVersionParser<?> versionParser;
+
+	private boolean versionRequired = true;
+
+	private @Nullable String defaultVersion;
+
+	private final Set<String> supportedVersions = new LinkedHashSet<>();
+
+
+	/**
+	 * Add a resolver that extracts the API version from a request header.
+	 * @param headerName the header name to check
+	 */
+	public ApiVersionConfigurer useRequestHeader(String headerName) {
+		this.versionResolvers.add(exchange -> exchange.getRequest().getHeaders().getFirst(headerName));
+		return this;
+	}
+
+	/**
+	 * Add a resolver that extracts the API version from a request parameter.
+	 * @param paramName the parameter name to check
+	 */
+	public ApiVersionConfigurer useRequestParam(String paramName) {
+		this.versionResolvers.add(exchange -> exchange.getRequest().getQueryParams().getFirst(paramName));
+		return this;
+	}
+
+	/**
+	 * Add a resolver that extracts the API version from a path segment.
+	 * @param index the index of the path segment to check; e.g. for URL's like
+	 * "/{version}/..." use index 0, for "/api/{version}/..." index 1.
+	 */
+	public ApiVersionConfigurer usePathSegment(int index) {
+		this.versionResolvers.add(new PathApiVersionResolver(index));
+		return this;
+	}
+
+	/**
+	 * Add custom resolvers to resolve the API version.
+	 * @param resolvers the resolvers to use
+	 */
+	public ApiVersionConfigurer useVersionResolver(ApiVersionResolver... resolvers) {
+		this.versionResolvers.addAll(Arrays.asList(resolvers));
+		return this;
+	}
+
+	/**
+	 * Configure a parser to parse API versions with.
+	 * <p>By default, {@link SemanticApiVersionParser} is used.
+	 * @param versionParser the parser to user
+	 */
+	public ApiVersionConfigurer setVersionParser(@Nullable ApiVersionParser<?> versionParser) {
+		this.versionParser = versionParser;
+		return this;
+	}
+
+	/**
+	 * Whether requests are required to have an API version. When set to
+	 * {@code true}, {@link org.springframework.web.accept.MissingApiVersionException}
+	 * is raised, resulting in a 400 response if the request doesn't have an API
+	 * version. When set to false, a request without a version is considered to
+	 * accept any version.
+	 * <p>By default, this is set to {@code true} when API versioning is enabled
+	 * by adding at least one {@link ApiVersionResolver}). When a
+	 * {@link #setDefaultVersion defaultVersion} is also set, this is
+	 * automatically set to {@code false}.
+	 * @param required whether an API version is required.
+	 */
+	public ApiVersionConfigurer setVersionRequired(boolean required) {
+		this.versionRequired = required;
+		return this;
+	}
+
+	/**
+	 * Configure a default version to assign to requests that don't specify one.
+	 * @param defaultVersion the default version to use
+	 */
+	public ApiVersionConfigurer setDefaultVersion(@Nullable String defaultVersion) {
+		this.defaultVersion = defaultVersion;
+		return this;
+	}
+
+	/**
+	 * Add to the list of supported versions to validate request versions against.
+	 * Request versions that are not supported result in
+	 * {@link org.springframework.web.accept.InvalidApiVersionException}.
+	 * <p>Note that the set of supported versions is populated from versions
+	 * listed in controller mappings. Therefore, typically you do not have to
+	 * manage this list except for the initial API version, when controller
+	 * don't have to have a version to start.
+	 * @param versions supported versions to add
+	 */
+	public ApiVersionConfigurer addSupportedVersions(String... versions) {
+		Collections.addAll(this.supportedVersions, versions);
+		return this;
+	}
+
+	protected @Nullable ApiVersionStrategy getApiVersionStrategy() {
+		if (this.versionResolvers.isEmpty()) {
+			return null;
+		}
+
+		DefaultApiVersionStrategy strategy = new DefaultApiVersionStrategy(this.versionResolvers,
+				(this.versionParser != null ? this.versionParser : new SemanticApiVersionParser()),
+				this.versionRequired, this.defaultVersion);
+
+		this.supportedVersions.forEach(strategy::addSupportedVersion);
+
+		return strategy;
+	}
+
+}

spring-webflux/src/main/java/org/springframework/web/reactive/config/DelegatingWebFluxConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2024 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -92,6 +92,11 @@ public class DelegatingWebFluxConfiguration extends WebFluxConfigurationSupport
 		this.configurers.configureContentTypeResolver(builder);
 	}
 
+	@Override
+	protected void configureApiVersioning(ApiVersionConfigurer configurer) {
+		this.configurers.configureApiVersioning(configurer);
+	}
+
 	@Override
 	public void configurePathMatching(PathMatchConfigurer configurer) {
 		this.configurers.configurePathMatching(configurer);

spring-webflux/src/main/java/org/springframework/web/reactive/config/WebFluxConfigurationSupport.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2024 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -51,6 +51,7 @@ import org.springframework.web.bind.support.ConfigurableWebBindingInitializer;
 import org.springframework.web.cors.CorsConfiguration;
 import org.springframework.web.reactive.DispatcherHandler;
 import org.springframework.web.reactive.HandlerMapping;
+import org.springframework.web.reactive.accept.ApiVersionStrategy;
 import org.springframework.web.reactive.accept.RequestedContentTypeResolver;
 import org.springframework.web.reactive.accept.RequestedContentTypeResolverBuilder;
 import org.springframework.web.reactive.function.server.support.HandlerFunctionAdapter;
@@ -97,6 +98,8 @@ public class WebFluxConfigurationSupport implements ApplicationContextAware {
 
 	private @Nullable BlockingExecutionConfigurer blockingExecutionConfigurer;
 
+	private @Nullable ApiVersionStrategy apiVersionStrategy;
+
 	private @Nullable List<ErrorResponse.Interceptor> errorResponseInterceptors;
 
 	private @Nullable ViewResolverRegistry viewResolverRegistry;
@@ -132,13 +135,17 @@ public class WebFluxConfigurationSupport implements ApplicationContextAware {
 
 	@Bean
 	public RequestMappingHandlerMapping requestMappingHandlerMapping(
-			@Qualifier("webFluxContentTypeResolver") RequestedContentTypeResolver contentTypeResolver) {
+			@Qualifier("webFluxContentTypeResolver") RequestedContentTypeResolver contentTypeResolver,
+			@Qualifier("mvcApiVersionStrategy") @Nullable ApiVersionStrategy apiVersionStrategy) {
 
 		RequestMappingHandlerMapping mapping = createRequestMappingHandlerMapping();
 		mapping.setOrder(0);
 		mapping.setContentTypeResolver(contentTypeResolver);
+		mapping.setApiVersionStrategy(apiVersionStrategy);
+
 		PathMatchConfigurer configurer = getPathMatchConfigurer();
 		configureAbstractHandlerMapping(mapping, configurer);
+
 		Map<String, Predicate<Class<?>>> pathPrefixes = configurer.getPathPrefixes();
 		if (pathPrefixes != null) {
 			mapping.setPathPrefixes(pathPrefixes);
@@ -175,6 +182,31 @@ public class WebFluxConfigurationSupport implements ApplicationContextAware {
 	protected void configureContentTypeResolver(RequestedContentTypeResolverBuilder builder) {
 	}
 
+	/**
+	 * Return the central strategy to manage API versioning with, or {@code null}
+	 * if the application does not use versioning.
+	 * @since 7.0
+	 */
+	@Bean
+	public @Nullable ApiVersionStrategy mvcApiVersionStrategy() {
+		if (this.apiVersionStrategy == null) {
+			ApiVersionConfigurer configurer = new ApiVersionConfigurer();
+			configureApiVersioning(configurer);
+			ApiVersionStrategy strategy = configurer.getApiVersionStrategy();
+			if (strategy != null) {
+				this.apiVersionStrategy = strategy;
+			}
+		}
+		return this.apiVersionStrategy;
+	}
+
+	/**
+	 * Override this method to configure API versioning.
+	 * @since 7.0
+	 */
+	protected void configureApiVersioning(ApiVersionConfigurer configurer) {
+	}
+
 	/**
 	 * Callback for building the global CORS configuration. This method is final.
 	 * Use {@link #addCorsMappings(CorsRegistry)} to customize the CORS config.

spring-webflux/src/main/java/org/springframework/web/reactive/config/WebFluxConfigurer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2024 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -118,6 +118,15 @@ public interface WebFluxConfigurer {
 	default void configureContentTypeResolver(RequestedContentTypeResolverBuilder builder) {
 	}
 
+	/**
+	 * Configure API versioning for the application. In order for versioning to
+	 * be enabled, you must configure at least one way to resolve the API
+	 * version from a request (e.g. via request header).
+	 * @since 7.0
+	 */
+	default void configureApiVersioning(ApiVersionConfigurer configurer) {
+	}
+
 	/**
 	 * Configure path matching options.
 	 * <p>The configured path matching options will be used for mapping to

spring-webflux/src/main/java/org/springframework/web/reactive/config/WebFluxConfigurerComposite.java

@@ -89,6 +89,13 @@ public class WebFluxConfigurerComposite implements WebFluxConfigurer {
 		this.delegates.forEach(delegate -> delegate.configureContentTypeResolver(builder));
 	}
 
+	@Override
+	public void configureApiVersioning(ApiVersionConfigurer configurer) {
+		for (WebFluxConfigurer delegate : this.delegates) {
+			delegate.configureApiVersioning(configurer);
+		}
+	}
+
 	@Override
 	public void configurePathMatching(PathMatchConfigurer configurer) {
 		this.delegates.forEach(delegate -> delegate.configurePathMatching(configurer));

spring-webflux/src/main/java/org/springframework/web/reactive/result/condition/VersionRequestCondition.java

@@ -0,0 +1,203 @@
+/*
+ * Copyright 2002-2025 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
+ *
+ *      https://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.result.condition;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Set;
+
+import org.jspecify.annotations.Nullable;
+
+import org.springframework.util.Assert;
+import org.springframework.web.accept.InvalidApiVersionException;
+import org.springframework.web.accept.NotAcceptableApiVersionException;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.reactive.accept.ApiVersionStrategy;
+import org.springframework.web.server.ServerWebExchange;
+
+/**
+ * Request condition to map based on the API version of the request.
+ * Versions can be fixed (e.g. "1.2") or baseline (e.g. "1.2+") as described
+ * in {@link RequestMapping#version()}.
+ *
+ *
+ * @author Rossen Stoyanchev
+ * @since 7.0
+ */
+public final class VersionRequestCondition extends AbstractRequestCondition<VersionRequestCondition> {
+
+	private static final String VERSION_ATTRIBUTE_NAME = VersionRequestCondition.class.getName() + ".VERSION";
+
+	private static final String NO_VERSION_ATTRIBUTE = "NO_VERSION";
+
+	private static final ApiVersionStrategy NO_OP_VERSION_STRATEGY = new NoOpApiVersionStrategy();
+
+
+	private final @Nullable String versionValue;
+
+	private final @Nullable Object version;
+
+	private final boolean baselineVersion;
+
+	private final ApiVersionStrategy versionStrategy;
+
+	private final Set<String> content;
+
+
+	public VersionRequestCondition() {
+		this.versionValue = null;
+		this.version = null;
+		this.baselineVersion = false;
+		this.versionStrategy = NO_OP_VERSION_STRATEGY;
+		this.content = Collections.emptySet();
+	}
+
+	public VersionRequestCondition(String configuredVersion, ApiVersionStrategy versionStrategy) {
+		this.baselineVersion = configuredVersion.endsWith("+");
+		this.versionValue = updateVersion(configuredVersion, this.baselineVersion);
+		this.version = versionStrategy.parseVersion(this.versionValue);
+		this.versionStrategy = versionStrategy;
+		this.content = Set.of(configuredVersion);
+	}
+
+	private static String updateVersion(String version, boolean baselineVersion) {
+		return (baselineVersion ? version.substring(0, version.length() - 1) : version);
+	}
+
+
+	@Override
+	protected Collection<String> getContent() {
+		return this.content;
+	}
+
+	@Override
+	protected String getToStringInfix() {
+		return " && ";
+	}
+
+	public @Nullable String getVersion() {
+		return this.versionValue;
+	}
+
+	@Override
+	public VersionRequestCondition combine(VersionRequestCondition other) {
+		return (other.version != null ? other : this);
+	}
+
+	@Override
+	public @Nullable VersionRequestCondition getMatchingCondition(ServerWebExchange exchange) {
+		if (this.version == null) {
+			return this;
+		}
+
+		Comparable<?> version = exchange.getAttribute(VERSION_ATTRIBUTE_NAME);
+		if (version == null) {
+			String value = this.versionStrategy.resolveVersion(exchange);
+			version = (value != null ? parseVersion(value) : this.versionStrategy.getDefaultVersion());
+			this.versionStrategy.validateVersion(version, exchange);
+			version = (version != null ? version : NO_VERSION_ATTRIBUTE);
+			exchange.getAttributes().put(VERSION_ATTRIBUTE_NAME, (version));
+		}
+
+		if (version == NO_VERSION_ATTRIBUTE) {
+			return this;
+		}
+
+		// At this stage, match all versions as baseline versions.
+		// Strict matching for fixed versions is enforced at the end in handleMatch.
+
+		int result = compareVersions(this.version, version);
+		return (result <= 0 ? this : null);
+	}
+
+	private Comparable<?> parseVersion(String value) {
+		try {
+			return this.versionStrategy.parseVersion(value);
+		}
+		catch (Exception ex) {
+			throw new InvalidApiVersionException(value, null, ex);
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	private <V extends Comparable<V>> int compareVersions(Object v1, Object v2) {
+		return ((V) v1).compareTo((V) v2);
+	}
+
+	@Override
+	public int compareTo(VersionRequestCondition other, ServerWebExchange exchange) {
+		Object otherVersion = other.version;
+		if (this.version == null && otherVersion == null) {
+			return 0;
+		}
+		else if (this.version != null && otherVersion != null) {
+			// make higher version bubble up
+			return (-1 * compareVersions(this.version, otherVersion));
+		}
+		else {
+			return (this.version != null ? -1 : 1);
+		}
+	}
+
+	/**
+	 * Perform a final check on the matched request mapping version.
+	 * <p>In order to ensure baseline versions are properly capped by higher
+	 * fixed versions, initially we match all versions as baseline versions in
+	 * {@link #getMatchingCondition(ServerWebExchange)}. Once the highest of
+	 * potentially multiple matches is selected, we enforce the strict match
+	 * for fixed versions.
+	 * <p>For example, given controller methods for "1.2+" and "1.5", and
+	 * a request for "1.6", both are matched, allowing "1.5" to be selected, but
+	 * that is then rejected as not acceptable since it is not an exact match.
+	 * @param exchange the current exchange
+	 * @throws NotAcceptableApiVersionException if the matched condition has a
+	 * fixed version that is not equal to the request version
+	 */
+	public void handleMatch(ServerWebExchange exchange) {
+		if (this.version != null && !this.baselineVersion) {
+			Comparable<?> version = exchange.getAttribute(VERSION_ATTRIBUTE_NAME);
+			Assert.state(version != null, "No API version attribute");
+			if (!this.version.equals(version)) {
+				throw new NotAcceptableApiVersionException(version.toString());
+			}
+		}
+	}
+
+
+	private static final class NoOpApiVersionStrategy implements ApiVersionStrategy {
+
+		@Override
+		public @Nullable String resolveVersion(ServerWebExchange exchange) {
+			return null;
+		}
+
+		@Override
+		public String parseVersion(String version) {
+			return version;
+		}
+
+		@Override
+		public void validateVersion(@Nullable Comparable<?> requestVersion, ServerWebExchange exchange) {
+		}
+
+		@Override
+		public @Nullable Comparable<?> getDefaultVersion() {
+			return null;
+		}
+	}
+
+}

spring-webflux/src/main/java/org/springframework/web/reactive/result/method/RequestMappingInfo.java

@@ -23,9 +23,11 @@ import java.util.Set;
 
 import org.jspecify.annotations.Nullable;
 
+import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;
 import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.reactive.accept.ApiVersionStrategy;
 import org.springframework.web.reactive.accept.RequestedContentTypeResolver;
 import org.springframework.web.reactive.result.condition.ConsumesRequestCondition;
 import org.springframework.web.reactive.result.condition.HeadersRequestCondition;
@@ -35,6 +37,7 @@ import org.springframework.web.reactive.result.condition.ProducesRequestConditio
 import org.springframework.web.reactive.result.condition.RequestCondition;
 import org.springframework.web.reactive.result.condition.RequestConditionHolder;
 import org.springframework.web.reactive.result.condition.RequestMethodsRequestCondition;
+import org.springframework.web.reactive.result.condition.VersionRequestCondition;
 import org.springframework.web.server.ServerWebExchange;
 import org.springframework.web.util.pattern.PathPattern;
 import org.springframework.web.util.pattern.PathPatternParser;
@@ -68,6 +71,8 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 
 	private static final ProducesRequestCondition EMPTY_PRODUCES = new ProducesRequestCondition();
 
+	private static final VersionRequestCondition EMPTY_VERSION = new VersionRequestCondition();
+
 	private static final RequestConditionHolder EMPTY_CUSTOM = new RequestConditionHolder(null);
 
 
@@ -85,6 +90,8 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 
 	private final ProducesRequestCondition producesCondition;
 
+	private final VersionRequestCondition versionCondition;
+
 	private final RequestConditionHolder customConditionHolder;
 
 	private final int hashCode;
@@ -95,8 +102,8 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 	private RequestMappingInfo(@Nullable String name, @Nullable PatternsRequestCondition patterns,
 			@Nullable RequestMethodsRequestCondition methods, @Nullable ParamsRequestCondition params,
 			@Nullable HeadersRequestCondition headers, @Nullable ConsumesRequestCondition consumes,
-			@Nullable ProducesRequestCondition produces, @Nullable RequestCondition<?> custom,
-			BuilderConfiguration options) {
+			@Nullable ProducesRequestCondition produces, @Nullable VersionRequestCondition version,
+			@Nullable RequestCondition<?> custom, BuilderConfiguration options) {
 
 		this.name = (StringUtils.hasText(name) ? name : null);
 		this.patternsCondition = (patterns != null ? patterns : EMPTY_PATTERNS);
@@ -105,12 +112,13 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 		this.headersCondition = (headers != null ? headers : EMPTY_HEADERS);
 		this.consumesCondition = (consumes != null ? consumes : EMPTY_CONSUMES);
 		this.producesCondition = (produces != null ? produces : EMPTY_PRODUCES);
+		this.versionCondition = (version != null ? version : EMPTY_VERSION);
 		this.customConditionHolder = (custom != null ? new RequestConditionHolder(custom) : EMPTY_CUSTOM);
 		this.options = options;
 
 		this.hashCode = calculateHashCode(
 				this.patternsCondition, this.methodsCondition, this.paramsCondition, this.headersCondition,
-				this.consumesCondition, this.producesCondition, this.customConditionHolder);
+				this.consumesCondition, this.producesCondition, this.versionCondition, this.customConditionHolder);
 	}
 
 
@@ -177,6 +185,15 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 		return this.producesCondition;
 	}
 
+	/**
+	 * Returns the version condition of this {@link RequestMappingInfo},
+	 * or an instance without a version.
+	 * @since 7.0
+	 */
+	public VersionRequestCondition getVersionCondition() {
+		return this.versionCondition;
+	}
+
 	/**
 	 * Returns the "custom" condition of this {@link RequestMappingInfo}; or {@code null}.
 	 */
@@ -199,10 +216,11 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 		HeadersRequestCondition headers = this.headersCondition.combine(other.headersCondition);
 		ConsumesRequestCondition consumes = this.consumesCondition.combine(other.consumesCondition);
 		ProducesRequestCondition produces = this.producesCondition.combine(other.producesCondition);
+		VersionRequestCondition version = this.versionCondition.combine(other.versionCondition);
 		RequestConditionHolder custom = this.customConditionHolder.combine(other.customConditionHolder);
 
 		return new RequestMappingInfo(name, patterns,
-				methods, params, headers, consumes, produces, custom.getCondition(), this.options);
+				methods, params, headers, consumes, produces, version, custom.getCondition(), this.options);
 	}
 
 	private @Nullable String combineNames(RequestMappingInfo other) {
@@ -247,6 +265,10 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 		if (produces == null) {
 			return null;
 		}
+		VersionRequestCondition version = this.versionCondition.getMatchingCondition(exchange);
+		if (version == null) {
+			return null;
+		}
 		PatternsRequestCondition patterns = this.patternsCondition.getMatchingCondition(exchange);
 		if (patterns == null) {
 			return null;
@@ -256,7 +278,7 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 			return null;
 		}
 		return new RequestMappingInfo(this.name, patterns,
-				methods, params, headers, consumes, produces, custom.getCondition(), this.options);
+				methods, params, headers, consumes, produces, version, custom.getCondition(), this.options);
 	}
 
 	/**
@@ -287,6 +309,10 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 		if (result != 0) {
 			return result;
 		}
+		result = this.versionCondition.compareTo(other.getVersionCondition(), exchange);
+		if (result != 0) {
+			return result;
+		}
 		result = this.methodsCondition.compareTo(other.getMethodsCondition(), exchange);
 		if (result != 0) {
 			return result;
@@ -307,6 +333,7 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 				this.headersCondition.equals(that.headersCondition) &&
 				this.consumesCondition.equals(that.consumesCondition) &&
 				this.producesCondition.equals(that.producesCondition) &&
+				this.versionCondition.equals(that.versionCondition) &&
 				this.customConditionHolder.equals(that.customConditionHolder)));
 	}
 
@@ -319,10 +346,11 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 			PatternsRequestCondition patterns, RequestMethodsRequestCondition methods,
 			ParamsRequestCondition params, HeadersRequestCondition headers,
 			ConsumesRequestCondition consumes, ProducesRequestCondition produces,
-			RequestConditionHolder custom) {
+			VersionRequestCondition version, RequestConditionHolder custom) {
 
 		return patterns.hashCode() * 31 + methods.hashCode() + params.hashCode() +
-				headers.hashCode() + consumes.hashCode() + produces.hashCode() + custom.hashCode();
+				headers.hashCode() + consumes.hashCode() + produces.hashCode() +
+				version.hashCode() + custom.hashCode();
 	}
 
 	@Override
@@ -348,6 +376,9 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 		if (!this.producesCondition.isEmpty()) {
 			builder.append(", produces ").append(this.producesCondition);
 		}
+		if (!this.versionCondition.isEmpty()) {
+			builder.append(", version ").append(this.versionCondition);
+		}
 		if (!this.customConditionHolder.isEmpty()) {
 			builder.append(", and ").append(this.customConditionHolder);
 		}
@@ -410,6 +441,12 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 		 */
 		Builder produces(String... produces);
 
+		/**
+		 * Set the API version condition.
+		 * @since 7.0
+		 */
+		Builder version(String version);
+
 		/**
 		 * Set the mapping name.
 		 */
@@ -446,6 +483,8 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 
 		private String @Nullable [] produces;
 
+		private @Nullable String version;
+
 		private boolean hasContentType;
 
 		private boolean hasAccept;
@@ -456,7 +495,6 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 
 		private BuilderConfiguration options = new BuilderConfiguration();
 
-
 		public DefaultBuilder(String... paths) {
 			this.paths = paths;
 		}
@@ -503,6 +541,12 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 			return this;
 		}
 
+		@Override
+		public Builder version(String version) {
+			this.version = version;
+			return this;
+		}
+
 		@Override
 		public DefaultBuilder mappingName(String name) {
 			this.mappingName = name;
@@ -528,6 +572,16 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 
 			RequestedContentTypeResolver contentTypeResolver = this.options.getContentTypeResolver();
 
+			VersionRequestCondition versionCondition;
+			ApiVersionStrategy versionStrategy = this.options.getApiVersionStrategy();
+			if (StringUtils.hasText(this.version)) {
+				Assert.state(versionStrategy != null, "API version specified, but no ApiVersionStrategy configured");
+				versionCondition = new VersionRequestCondition(this.version, versionStrategy);
+			}
+			else {
+				versionCondition = EMPTY_VERSION;
+			}
+
 			return new RequestMappingInfo(this.mappingName,
 					isEmpty(this.paths) ? null : new PatternsRequestCondition(parse(this.paths, parser)),
 					ObjectUtils.isEmpty(this.methods) ?
@@ -540,6 +594,7 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 							null : new ConsumesRequestCondition(this.consumes, this.headers),
 					ObjectUtils.isEmpty(this.produces) && !this.hasAccept ?
 							null : new ProducesRequestCondition(this.produces, this.headers, contentTypeResolver),
+					versionCondition,
 					this.customCondition,
 					this.options);
 		}
@@ -585,6 +640,8 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 
 		private ProducesRequestCondition producesCondition;
 
+		private VersionRequestCondition versionCondition;
+
 		private RequestConditionHolder customConditionHolder;
 
 		private BuilderConfiguration options;
@@ -597,6 +654,7 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 			this.headersCondition = other.headersCondition;
 			this.consumesCondition = other.consumesCondition;
 			this.producesCondition = other.producesCondition;
+			this.versionCondition = other.versionCondition;
 			this.customConditionHolder = other.customConditionHolder;
 			this.options = other.options;
 		}
@@ -646,6 +704,19 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 			return this;
 		}
 
+		@Override
+		public Builder version(@Nullable String version) {
+			if (version != null) {
+				ApiVersionStrategy strategy = this.options.getApiVersionStrategy();
+				Assert.state(strategy != null, "API version specified, but no ApiVersionStrategy configured");
+				this.versionCondition = new VersionRequestCondition(version, strategy);
+			}
+			else {
+				this.versionCondition = EMPTY_VERSION;
+			}
+			return this;
+		}
+
 		@Override
 		public Builder mappingName(String name) {
 			this.name = name;
@@ -668,7 +739,7 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 		public RequestMappingInfo build() {
 			return new RequestMappingInfo(this.name, this.patternsCondition,
 					this.methodsCondition, this.paramsCondition, this.headersCondition,
-					this.consumesCondition, this.producesCondition,
+					this.consumesCondition, this.producesCondition, this.versionCondition,
 					this.customConditionHolder, this.options);
 		}
 	}
@@ -686,6 +757,8 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 
 		private @Nullable RequestedContentTypeResolver contentTypeResolver;
 
+		private @Nullable ApiVersionStrategy apiVersionStrategy;
+
 		public void setPatternParser(PathPatternParser patternParser) {
 			this.patternParser = patternParser;
 		}
@@ -705,6 +778,23 @@ public final class RequestMappingInfo implements RequestCondition<RequestMapping
 		public @Nullable RequestedContentTypeResolver getContentTypeResolver() {
 			return this.contentTypeResolver;
 		}
+
+		/**
+		 * Set the strategy for API versioning.
+		 * @param apiVersionStrategy the strategy to use
+		 * @since 7.0
+		 */
+		public void setApiVersionStrategy(@Nullable ApiVersionStrategy apiVersionStrategy) {
+			this.apiVersionStrategy = apiVersionStrategy;
+		}
+
+		/**
+		 * Return the configured strategy for API versioning.
+		 * @since 7.0
+		 */
+		public @Nullable ApiVersionStrategy getApiVersionStrategy() {
+			return this.apiVersionStrategy;
+		}
 	}
 
 }

spring-webflux/src/main/java/org/springframework/web/reactive/result/method/RequestMappingInfoHandlerMapping.java

@@ -120,6 +120,8 @@ public abstract class RequestMappingInfoHandlerMapping extends AbstractHandlerMe
 
 		super.handleMatch(info, handlerMethod, exchange);
 
+		info.getVersionCondition().handleMatch(exchange);
+
 		PathContainer lookupPath = exchange.getRequest().getPath().pathWithinApplication();
 
 		PathPattern bestPattern;

spring-webflux/src/main/java/org/springframework/web/reactive/result/method/annotation/RequestMappingHandlerMapping.java

@@ -47,6 +47,8 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.cors.CorsConfiguration;
 import org.springframework.web.method.HandlerMethod;
+import org.springframework.web.reactive.accept.ApiVersionStrategy;
+import org.springframework.web.reactive.accept.DefaultApiVersionStrategy;
 import org.springframework.web.reactive.accept.RequestedContentTypeResolver;
 import org.springframework.web.reactive.accept.RequestedContentTypeResolverBuilder;
 import org.springframework.web.reactive.result.condition.ConsumesRequestCondition;
@@ -78,6 +80,8 @@ public class RequestMappingHandlerMapping extends RequestMappingInfoHandlerMappi
 
 	private RequestedContentTypeResolver contentTypeResolver = new RequestedContentTypeResolverBuilder().build();
 
+	private @Nullable ApiVersionStrategy apiVersionStrategy;
+
 	private @Nullable StringValueResolver embeddedValueResolver;
 
 	private RequestMappingInfo.BuilderConfiguration config = new RequestMappingInfo.BuilderConfiguration();
@@ -126,6 +130,23 @@ public class RequestMappingHandlerMapping extends RequestMappingInfoHandlerMappi
 		return this.contentTypeResolver;
 	}
 
+	/**
+	 * Configure a strategy to manage API versioning.
+	 * @param strategy the strategy to use
+	 * @since 7.0
+	 */
+	public void setApiVersionStrategy(@Nullable ApiVersionStrategy strategy) {
+		this.apiVersionStrategy = strategy;
+	}
+
+	/**
+	 * Return the configured {@link ApiVersionStrategy} strategy.
+	 * @since 7.0
+	 */
+	public @Nullable ApiVersionStrategy getApiVersionStrategy() {
+		return this.apiVersionStrategy;
+	}
+
 	@Override
 	public void setEmbeddedValueResolver(StringValueResolver resolver) {
 		this.embeddedValueResolver = resolver;
@@ -136,6 +157,7 @@ public class RequestMappingHandlerMapping extends RequestMappingInfoHandlerMappi
 		this.config = new RequestMappingInfo.BuilderConfiguration();
 		this.config.setPatternParser(getPathPatternParser());
 		this.config.setContentTypeResolver(getContentTypeResolver());
+		this.config.setApiVersionStrategy(getApiVersionStrategy());
 
 		super.afterPropertiesSet();
 	}
@@ -214,6 +236,13 @@ public class RequestMappingHandlerMapping extends RequestMappingInfoHandlerMappi
 			requestMappingInfo = createRequestMappingInfo((HttpExchange) httpExchanges.get(0).annotation, customCondition);
 		}
 
+		if (requestMappingInfo != null && this.apiVersionStrategy instanceof DefaultApiVersionStrategy davs) {
+			String version = requestMappingInfo.getVersionCondition().getVersion();
+			if (version != null) {
+				davs.addSupportedVersion(version);
+			}
+		}
+
 		return requestMappingInfo;
 	}
 
@@ -269,6 +298,7 @@ public class RequestMappingHandlerMapping extends RequestMappingInfoHandlerMappi
 				.headers(requestMapping.headers())
 				.consumes(requestMapping.consumes())
 				.produces(requestMapping.produces())
+				.version(requestMapping.version())
 				.mappingName(requestMapping.name());
 
 		if (customCondition != null) {

spring-webflux/src/test/java/org/springframework/web/reactive/accept/DefaultApiVersionStrategiesTests.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2002-2025 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
+ *
+ *      https://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.accept;
+
+import java.util.List;
+
+import org.jspecify.annotations.Nullable;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.web.accept.InvalidApiVersionException;
+import org.springframework.web.accept.SemanticApiVersionParser;
+import org.springframework.web.server.ServerWebExchange;
+import org.springframework.web.testfixture.http.server.reactive.MockServerHttpRequest;
+import org.springframework.web.testfixture.server.MockServerWebExchange;
+
+import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
+import static org.assertj.core.api.AssertionsForClassTypes.assertThatThrownBy;
+
+/**
+ * Unit tests for {@link org.springframework.web.accept.DefaultApiVersionStrategy}.
+ * @author Rossen Stoyanchev
+ */
+public class DefaultApiVersionStrategiesTests {
+
+	private final SemanticApiVersionParser parser = new SemanticApiVersionParser();
+
+
+	@Test
+	void defaultVersion() {
+		SemanticApiVersionParser.Version version = this.parser.parseVersion("1.2.3");
+		ApiVersionStrategy strategy = initVersionStrategy(version.toString());
+
+		assertThat(strategy.getDefaultVersion()).isEqualTo(version);
+	}
+
+	@Test
+	void supportedVersions() {
+		SemanticApiVersionParser.Version v1 = this.parser.parseVersion("1");
+		SemanticApiVersionParser.Version v2 = this.parser.parseVersion("2");
+		SemanticApiVersionParser.Version v9 = this.parser.parseVersion("9");
+
+		DefaultApiVersionStrategy strategy = initVersionStrategy(null);
+		strategy.addSupportedVersion(v1.toString());
+		strategy.addSupportedVersion(v2.toString());
+
+		ServerWebExchange exchange = MockServerWebExchange.from(MockServerHttpRequest.get("/"));
+		strategy.validateVersion(v1, exchange);
+		strategy.validateVersion(v2, exchange);
+
+		assertThatThrownBy(() -> strategy.validateVersion(v9, exchange))
+				.isInstanceOf(InvalidApiVersionException.class);
+	}
+
+	private static DefaultApiVersionStrategy initVersionStrategy(@Nullable String defaultValue) {
+		return new DefaultApiVersionStrategy(
+				List.of(exchange -> exchange.getRequest().getQueryParams().getFirst("api-version")),
+				new SemanticApiVersionParser(), true, defaultValue);
+	}
+
+}

spring-webflux/src/test/java/org/springframework/web/reactive/accept/PathApiVersionResolverTests.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2002-2025 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
+ *
+ *      https://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.accept;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.web.server.ServerWebExchange;
+import org.springframework.web.testfixture.http.server.reactive.MockServerHttpRequest;
+import org.springframework.web.testfixture.server.MockServerWebExchange;
+
+import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
+
+/**
+ * Unit tests for {@link org.springframework.web.accept.PathApiVersionResolver}.
+ * @author Rossen Stoyanchev
+ */
+public class PathApiVersionResolverTests {
+
+	@Test
+	void resolve() {
+		testResolve(0, "/1.0/path", "1.0");
+		testResolve(1, "/app/1.1/path", "1.1");
+	}
+
+	private static void testResolve(int index, String requestUri, String expected) {
+		ServerWebExchange exchange = MockServerWebExchange.from(MockServerHttpRequest.get(requestUri));
+		String actual = new PathApiVersionResolver(index).resolveVersion(exchange);
+		assertThat(actual).isEqualTo(expected);
+	}
+
+}

spring-webflux/src/test/java/org/springframework/web/reactive/config/DelegatingWebFluxConfigurationTests.java

@@ -86,7 +86,8 @@ public class DelegatingWebFluxConfigurationTests {
 	@Test
 	void requestMappingHandlerMapping() {
 		delegatingConfig.setConfigurers(Collections.singletonList(webFluxConfigurer));
-		delegatingConfig.requestMappingHandlerMapping(delegatingConfig.webFluxContentTypeResolver());
+		delegatingConfig.requestMappingHandlerMapping(
+				delegatingConfig.webFluxContentTypeResolver(), delegatingConfig.mvcApiVersionStrategy());
 
 		verify(webFluxConfigurer).configureContentTypeResolver(any(RequestedContentTypeResolverBuilder.class));
 		verify(webFluxConfigurer).addCorsMappings(any(CorsRegistry.class));

spring-webflux/src/test/java/org/springframework/web/reactive/result/condition/VersionRequestConditionTests.java

@@ -0,0 +1,172 @@
+/*
+ * Copyright 2002-2025 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
+ *
+ *      https://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.result.condition;
+
+import java.util.Arrays;
+import java.util.List;
+
+import org.jspecify.annotations.Nullable;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.web.accept.NotAcceptableApiVersionException;
+import org.springframework.web.accept.SemanticApiVersionParser;
+import org.springframework.web.reactive.accept.DefaultApiVersionStrategy;
+import org.springframework.web.server.ServerWebExchange;
+import org.springframework.web.testfixture.http.server.reactive.MockServerHttpRequest;
+import org.springframework.web.testfixture.server.MockServerWebExchange;
+
+import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
+import static org.assertj.core.api.AssertionsForClassTypes.assertThatThrownBy;
+
+/**
+ * Unit tests for {@link VersionRequestCondition}.
+ * @author Rossen Stoyanchev
+ */
+public class VersionRequestConditionTests {
+
+	private DefaultApiVersionStrategy strategy;
+
+
+	@BeforeEach
+	void setUp() {
+		this.strategy = initVersionStrategy(null);
+	}
+
+	private static DefaultApiVersionStrategy initVersionStrategy(@Nullable String defaultValue) {
+		return new DefaultApiVersionStrategy(
+				List.of(exchange -> exchange.getRequest().getQueryParams().getFirst("api-version")),
+				new SemanticApiVersionParser(), true, defaultValue);
+	}
+
+	@Test
+	void combineMethodLevelOnly() {
+		VersionRequestCondition condition = emptyCondition().combine(condition("1.1"));
+		assertThat(condition.getVersion()).isEqualTo("1.1");
+	}
+
+	@Test
+	void combineTypeLevelOnly() {
+		VersionRequestCondition condition = condition("1.1").combine(emptyCondition());
+		assertThat(condition.getVersion()).isEqualTo("1.1");
+	}
+
+	@Test
+	void combineTypeAndMethodLevel() {
+		assertThat(condition("1.1").combine(condition("1.2")).getVersion()).isEqualTo("1.2");
+	}
+
+	@Test
+	void fixedVersionMatch() {
+		String conditionVersion = "1.2";
+		this.strategy.addSupportedVersion("1.1", "1.3");
+
+		testMatch("v1.1", conditionVersion, true, false);
+		testMatch("v1.2", conditionVersion, false, false);
+		testMatch("v1.3", conditionVersion, false, true);
+	}
+
+	@Test
+	void baselineVersionMatch() {
+		String conditionVersion = "1.2+";
+		this.strategy.addSupportedVersion("1.1", "1.3");
+
+		testMatch("v1.1", conditionVersion, true, false);
+		testMatch("v1.2", conditionVersion, false, false);
+		testMatch("v1.3", conditionVersion, false, false);
+	}
+
+	private void testMatch(
+			String requestVersion, String conditionVersion, boolean notCompatible, boolean notAcceptable) {
+
+		ServerWebExchange exchange = exchangeWithVersion(requestVersion);
+		VersionRequestCondition condition = condition(conditionVersion);
+		VersionRequestCondition match = condition.getMatchingCondition(exchange);
+
+		if (notCompatible) {
+			assertThat(match).isNull();
+			return;
+		}
+
+		assertThat(match).isSameAs(condition);
+
+		if (notAcceptable) {
+			assertThatThrownBy(() -> condition.handleMatch(exchange)).isInstanceOf(NotAcceptableApiVersionException.class);
+			return;
+		}
+
+		condition.handleMatch(exchange);
+	}
+
+	@Test
+	void missingRequiredVersion() {
+		assertThatThrownBy(() -> condition("1.2").getMatchingCondition(exchange()))
+				.hasMessage("400 BAD_REQUEST \"API version is required.\"");
+	}
+
+	@Test
+	void defaultVersion() {
+		String version = "1.2";
+		this.strategy = initVersionStrategy(version);
+		VersionRequestCondition condition = condition(version);
+		VersionRequestCondition match = condition.getMatchingCondition(exchange());
+
+		assertThat(match).isSameAs(condition);
+	}
+
+	@Test
+	void unsupportedVersion() {
+		assertThatThrownBy(() -> condition("1.2").getMatchingCondition(exchangeWithVersion("1.3")))
+				.hasMessage("400 BAD_REQUEST \"Invalid API version: '1.3.0'.\"");
+	}
+
+	@Test
+	void compare() {
+		testCompare("1.1", "1", "1.1");
+		testCompare("1.1.1", "1", "1.1", "1.1.1");
+		testCompare("10", "1.1", "10");
+		testCompare("10", "2", "10");
+	}
+
+	private void testCompare(String expected, String... versions) {
+		List<VersionRequestCondition> list = Arrays.stream(versions)
+				.map(this::condition)
+				.sorted((c1, c2) -> c1.compareTo(c2, exchange()))
+				.toList();
+
+		assertThat(list.get(0)).isEqualTo(condition(expected));
+	}
+
+	private VersionRequestCondition condition(String v) {
+		this.strategy.addSupportedVersion(v.endsWith("+") ? v.substring(0, v.length() - 1) : v);
+		return new VersionRequestCondition(v, this.strategy);
+	}
+
+	private VersionRequestCondition emptyCondition() {
+		return new VersionRequestCondition();
+	}
+
+	private static MockServerWebExchange exchange() {
+		return MockServerWebExchange.from(MockServerHttpRequest.get("/path"));
+	}
+
+	private ServerWebExchange exchangeWithVersion(String v) {
+		return MockServerWebExchange.from(
+				MockServerHttpRequest.get("/path").queryParam("api-version", v));
+	}
+
+}

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/RequestMappingVersionIntegrationTests.java

@@ -0,0 +1,110 @@
+/*
+ * Copyright 2002-2025 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
+ *
+ *      https://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.result.method.annotation;
+
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.http.RequestEntity;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.client.HttpClientErrorException;
+import org.springframework.web.reactive.config.ApiVersionConfigurer;
+import org.springframework.web.reactive.config.EnableWebFlux;
+import org.springframework.web.reactive.config.WebFluxConfigurer;
+import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+/**
+ * {@code @RequestMapping} integration focusing on API versioning.
+ * @author Rossen Stoyanchev
+ */
+public class RequestMappingVersionIntegrationTests extends AbstractRequestMappingIntegrationTests {
+
+	@Override
+	protected ApplicationContext initApplicationContext() {
+		AnnotationConfigApplicationContext wac = new AnnotationConfigApplicationContext();
+		wac.register(WebConfig.class, TestController.class);
+		wac.refresh();
+		return wac;
+	}
+
+
+	@ParameterizedHttpServerTest
+	void initialVersion(HttpServer httpServer) throws Exception {
+		startServer(httpServer);
+		assertThat(exchangeWithVersion("1.0").getBody()).isEqualTo("none");
+		assertThat(exchangeWithVersion("1.1").getBody()).isEqualTo("none");
+	}
+
+	@ParameterizedHttpServerTest
+	void baselineVersion(HttpServer httpServer) throws Exception {
+		startServer(httpServer);
+		assertThat(exchangeWithVersion("1.2").getBody()).isEqualTo("1.2");
+		assertThat(exchangeWithVersion("1.3").getBody()).isEqualTo("1.2");
+	}
+
+	@ParameterizedHttpServerTest
+	void fixedVersion(HttpServer httpServer) throws Exception {
+		startServer(httpServer);
+		assertThat(exchangeWithVersion("1.5").getBody()).isEqualTo("1.5");
+		assertThatThrownBy(() -> exchangeWithVersion("1.6")).isInstanceOf(HttpClientErrorException.BadRequest.class);
+	}
+
+	private ResponseEntity<String> exchangeWithVersion(String version) {
+		String url = "http://localhost:" + this.port;
+		RequestEntity<Void> requestEntity = RequestEntity.get(url).header("X-API-Version", version).build();
+		return getRestTemplate().exchange(requestEntity, String.class);
+	}
+
+
+	@EnableWebFlux
+	private static class WebConfig implements WebFluxConfigurer {
+
+		@Override
+		public void configureApiVersioning(ApiVersionConfigurer configurer) {
+			configurer.useRequestHeader("X-API-Version").addSupportedVersions("1", "1.1", "1.3", "1.6");
+		}
+	}
+
+
+	@RestController
+	private static class TestController {
+
+		@GetMapping
+		String noVersion() {
+			return getBody("none");
+		}
+
+		@GetMapping(version = "1.2+")
+		String version1_2() {
+			return getBody("1.2");
+		}
+
+		@GetMapping(version = "1.5")
+		String version1_5() {
+			return getBody("1.5");
+		}
+
+		private static String getBody(String version) {
+			return version;
+		}
+	}
+
+}