Add dedicated ApiVersionResolver implementations

Closes gh-35747

Author: rstoyanchev

spring-web/src/main/java/org/springframework/web/accept/HeaderApiVersionResolver.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2002-present 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.accept;
+
+
+import jakarta.servlet.http.HttpServletRequest;
+import org.jspecify.annotations.Nullable;
+
+/**
+ * {@link ApiVersionResolver} that extract the version from a header.
+ *
+ * @author Rossen Stoyanchev
+ * @since 7.0
+ */
+public class HeaderApiVersionResolver implements ApiVersionResolver {
+
+	private final String headerName;
+
+
+	public HeaderApiVersionResolver(String headerName) {
+		this.headerName = headerName;
+	}
+
+
+	@Override
+	public @Nullable String resolveVersion(HttpServletRequest request) {
+		return request.getHeader(this.headerName);
+	}
+
+}

spring-web/src/test/java/org/springframework/web/accept/HeaderApiVersionResolverTests.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2002-present 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.accept;
+
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.web.testfixture.servlet.MockHttpServletRequest;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Unit tests for {@link HeaderApiVersionResolver}.
+ * @author Rossen Stoyanchev
+ */
+public class HeaderApiVersionResolverTests {
+
+	private final String headerName = "Api-Version";
+
+	private final HeaderApiVersionResolver resolver = new HeaderApiVersionResolver(headerName);
+
+
+	@Test
+	void resolve() {
+		String version = "1.2";
+		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/path");
+		request.addHeader(headerName, version);
+		String actual = resolver.resolveVersion(request);
+		assertThat(actual).isEqualTo(version);
+	}
+
+	@Test
+	void noHeader() {
+		MockHttpServletRequest request = new MockHttpServletRequest("GET", "/path");
+		String version = resolver.resolveVersion(request);
+		assertThat(version).isNull();
+	}
+
+}

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

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2002-present 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;
+
+/**
+ * {@link ApiVersionResolver} that extract the version from a request header.
+ *
+ * @author Rossen Stoyanchev
+ * @since 7.0
+ */
+public class HeaderApiVersionResolver implements ApiVersionResolver {
+
+	private final String headerName;
+
+
+	public HeaderApiVersionResolver(String headerName) {
+		this.headerName = headerName;
+	}
+
+
+	@Override
+	public @Nullable String resolveVersion(ServerWebExchange exchange) {
+		return exchange.getRequest().getHeaders().getFirst(this.headerName);
+	}
+
+}

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

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2002-present 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;
+
+/**
+ * {@link ApiVersionResolver} that extract the version from a query parameter.
+ *
+ * @author Rossen Stoyanchev
+ * @since 7.0
+ */
+public class QueryApiVersionResolver implements ApiVersionResolver {
+
+	private final String queryParamName;
+
+
+	public QueryApiVersionResolver(String queryParamName) {
+		this.queryParamName = queryParamName;
+	}
+
+
+	@Override
+	public @Nullable String resolveVersion(ServerWebExchange exchange) {
+		return exchange.getRequest().getQueryParams().getFirst(this.queryParamName);
+	}
+
+}

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

@@ -35,8 +35,10 @@
 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.HeaderApiVersionResolver;
 import org.springframework.web.reactive.accept.MediaTypeParamApiVersionResolver;
 import org.springframework.web.reactive.accept.PathApiVersionResolver;
+import org.springframework.web.reactive.accept.QueryApiVersionResolver;
 import org.springframework.web.reactive.accept.StandardApiVersionDeprecationHandler;
 
 /**
@@ -69,7 +71,7 @@ public class ApiVersionConfigurer {
 	 * @param headerName the header name to check
 	 */
 	public ApiVersionConfigurer useRequestHeader(String headerName) {
-		this.versionResolvers.add(exchange -> exchange.getRequest().getHeaders().getFirst(headerName));
+		this.versionResolvers.add(new HeaderApiVersionResolver(headerName));
 		return this;
 	}
 
@@ -78,7 +80,7 @@ public ApiVersionConfigurer useRequestHeader(String headerName) {
 	 * @param paramName the parameter name to check
 	 */
 	public ApiVersionConfigurer useQueryParam(String paramName) {
-		this.versionResolvers.add(exchange -> exchange.getRequest().getQueryParams().getFirst(paramName));
+		this.versionResolvers.add(new QueryApiVersionResolver(paramName));
 		return this;
 	}
 

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

@@ -0,0 +1,54 @@
+/*
+ * Copyright 2002-present 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.server.MockServerWebExchange;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.springframework.web.testfixture.http.server.reactive.MockServerHttpRequest.get;
+
+/**
+ * Unit tests for {@link HeaderApiVersionResolver}.
+ * @author Rossen Stoyanchev
+ */
+public class HeaderApiVersionResolverTests {
+
+	private final String headerName = "Api-Version";
+
+	private final HeaderApiVersionResolver resolver = new HeaderApiVersionResolver(headerName);
+
+
+	@Test
+	void resolve() {
+		String version = "1.2";
+		ServerWebExchange exchange = MockServerWebExchange.from(get("/").header(headerName, version));
+		String actual = resolver.resolveVersion(exchange);
+		assertThat(actual).isEqualTo(version);
+	}
+
+	@Test
+	void noHeader() {
+		ServerWebExchange exchange = MockServerWebExchange.from(get("/"));
+		String version = resolver.resolveVersion(exchange);
+		assertThat(version).isNull();
+	}
+
+}

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

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2002-present 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.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.Assertions.assertThat;
+
+/**
+ * Unit tests for {@link QueryApiVersionResolver}.
+ * @author Rossen Stoyanchev
+ */
+public class QueryApiVersionResolverTests {
+
+	private final String queryParamName = "api-version";
+
+	private final QueryApiVersionResolver resolver = new QueryApiVersionResolver(queryParamName);
+
+
+	@Test
+	void resolve() {
+		ServerWebExchange exchange = initExchange("q=foo&" + queryParamName + "=1.2");
+		String version = resolver.resolveVersion(exchange);
+		assertThat(version).isEqualTo("1.2");
+	}
+
+	@Test
+	void noQueryString() {
+		ServerWebExchange exchange = initExchange(null);
+		String version = resolver.resolveVersion(exchange);
+		assertThat(version).isNull();
+	}
+
+	@Test
+	void noQueryParam() {
+		ServerWebExchange exchange = initExchange("q=foo");
+		String version = resolver.resolveVersion(exchange);
+		assertThat(version).isNull();
+	}
+
+	private static ServerWebExchange initExchange(@Nullable String queryString) {
+		return MockServerWebExchange.from(MockServerHttpRequest.get("/path?" + queryString));
+	}
+
+}

spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/ApiVersionConfigurer.java

@@ -33,6 +33,7 @@
 import org.springframework.web.accept.ApiVersionResolver;
 import org.springframework.web.accept.ApiVersionStrategy;
 import org.springframework.web.accept.DefaultApiVersionStrategy;
+import org.springframework.web.accept.HeaderApiVersionResolver;
 import org.springframework.web.accept.InvalidApiVersionException;
 import org.springframework.web.accept.MediaTypeParamApiVersionResolver;
 import org.springframework.web.accept.PathApiVersionResolver;
@@ -70,7 +71,7 @@ public class ApiVersionConfigurer {
 	 * @param headerName the header name to check
 	 */
 	public ApiVersionConfigurer useRequestHeader(String headerName) {
-		this.versionResolvers.add(request -> request.getHeader(headerName));
+		this.versionResolvers.add(new HeaderApiVersionResolver(headerName));
 		return this;
 	}