Support cookies with the same name with Reactor Netty

Ignore the related test with Undertow due to a bug in
their cookies handling.

Closes gh-28490

spring-web/src/main/java/org/springframework/http/server/reactive/ReactorNetty2ServerHttpRequest.java

@@ -50,6 +50,7 @@ import org.springframework.util.MultiValueMap;
  * <p>This class is based on {@link ReactorServerHttpRequest}.
  *
  * @author Violeta Georgieva
+ * @author Sebastien Deleuze
  * @since 6.0
  */
 class ReactorNetty2ServerHttpRequest extends AbstractServerHttpRequest {
@@ -144,8 +145,8 @@ class ReactorNetty2ServerHttpRequest extends AbstractServerHttpRequest {
 	@Override
 	protected MultiValueMap<String, HttpCookie> initCookies() {
 		MultiValueMap<String, HttpCookie> cookies = new LinkedMultiValueMap<>();
-		for (CharSequence name : this.request.cookies().keySet()) {
-			for (HttpCookiePair cookie : this.request.cookies().get(name)) {
+		for (CharSequence name : this.request.allCookies().keySet()) {
+			for (HttpCookiePair cookie : this.request.allCookies().get(name)) {
 				CharSequence cookieValue = cookie.value();
 				HttpCookie httpCookie = new HttpCookie(name.toString(), cookieValue != null ? cookieValue.toString() : null);
 				cookies.add(name.toString(), httpCookie);

spring-web/src/main/java/org/springframework/http/server/reactive/ReactorServerHttpRequest.java

@@ -75,8 +75,8 @@ class ReactorServerHttpRequest extends AbstractServerHttpRequest {
 	@Override
 	protected MultiValueMap<String, HttpCookie> initCookies() {
 		MultiValueMap<String, HttpCookie> cookies = new LinkedMultiValueMap<>();
-		for (CharSequence name : this.request.cookies().keySet()) {
-			for (Cookie cookie : this.request.cookies().get(name)) {
+		for (CharSequence name : this.request.allCookies().keySet()) {
+			for (Cookie cookie : this.request.allCookies().get(name)) {
 				HttpCookie httpCookie = new HttpCookie(name.toString(), cookie.value());
 				cookies.add(name.toString(), httpCookie);
 			}

spring-web/src/test/java/org/springframework/http/server/reactive/CookieIntegrationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 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.
@@ -30,11 +30,14 @@ import org.springframework.http.ResponseEntity;
 import org.springframework.web.client.RestTemplate;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.AbstractHttpHandlerIntegrationTests;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
+import org.springframework.web.testfixture.http.server.reactive.bootstrap.UndertowHttpServer;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assumptions.assumeFalse;
 
 /**
  * @author Rossen Stoyanchev
+ * @author Sebastien Deleuze
  */
 public class CookieIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 
@@ -81,6 +84,23 @@ public class CookieIntegrationTests extends AbstractHttpHandlerIntegrationTests
 				.containsExactlyInAnyOrder("path=/", "domain=example.com");
 	}
 
+	@ParameterizedHttpServerTest
+	public void cookiesWithSameNameTest(HttpServer httpServer) throws Exception {
+		assumeFalse(httpServer instanceof UndertowHttpServer, "Bug in Undertow in Cookies with same name handling");
+
+		startServer(httpServer);
+
+		URI url = new URI("http://localhost:" + port);
+		String header = "SID=31d4d96e407aad42; lang=en-US; lang=zh-CN";
+		new RestTemplate().exchange(
+				RequestEntity.get(url).header("Cookie", header).build(), Void.class);
+
+		Map<String, List<HttpCookie>> requestCookies = this.cookieHandler.requestCookies;
+		assertThat(requestCookies.size()).isEqualTo(2);
+		assertThat(requestCookies.get("SID")).extracting(HttpCookie::getValue).containsExactly("31d4d96e407aad42");
+		assertThat(requestCookies.get("lang")).extracting(HttpCookie::getValue).containsExactly("en-US", "zh-CN");
+	}
+
 	// No client side HttpCookie support yet
 	private List<String> splitCookie(String value) {
 		List<String> list = new ArrayList<>();