Filter out null WebSocketSession attributes

Closes gh-29315

spring-webflux/src/main/java/org/springframework/web/reactive/socket/adapter/AbstractWebSocketSession.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -73,9 +73,12 @@ public abstract class AbstractWebSocketSession<T> implements WebSocketSession {
 		this.id = id;
 		this.handshakeInfo = info;
 		this.bufferFactory = bufferFactory;
-		this.attributes.putAll(info.getAttributes());
 		this.logPrefix = initLogPrefix(info, id);
 
+		info.getAttributes().entrySet().stream()
+				.filter(entry -> (entry.getKey() != null && entry.getValue() != null))
+				.forEach(entry -> this.attributes.put(entry.getKey(), entry.getValue()));
+
 		if (logger.isDebugEnabled()) {
 			logger.debug(getLogPrefix() + "Session id \"" + getId() + "\" for " + getHandshakeInfo().getUri());
 		}

spring-websocket/src/main/java/org/springframework/web/socket/adapter/AbstractWebSocketSession.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -62,7 +62,9 @@ public abstract class AbstractWebSocketSession<T> implements NativeWebSocketSess
 	 */
 	public AbstractWebSocketSession(@Nullable Map<String, Object> attributes) {
 		if (attributes != null) {
-			this.attributes.putAll(attributes);
+			attributes.entrySet().stream()
+					.filter(entry -> (entry.getKey() != null && entry.getValue() != null))
+					.forEach(entry -> this.attributes.put(entry.getKey(), entry.getValue()));
 		}
 	}
 

spring-websocket/src/test/java/org/springframework/web/socket/adapter/standard/StandardWebSocketSessionTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -37,6 +37,7 @@ import static org.mockito.Mockito.verifyNoMoreInteractions;
  *
  * @author Rossen Stoyanchev
  */
+@SuppressWarnings("resource")
 public class StandardWebSocketSessionTests {
 
 	private final HttpHeaders headers = new HttpHeaders();
@@ -54,7 +55,6 @@ public class StandardWebSocketSessionTests {
 	}
 
 	@Test
-	@SuppressWarnings("resource")
 	public void getPrincipalWithNativeSession() {
 		TestPrincipal user = new TestPrincipal("joe");
 
@@ -68,7 +68,6 @@ public class StandardWebSocketSessionTests {
 	}
 
 	@Test
-	@SuppressWarnings("resource")
 	public void getPrincipalNone() {
 		Session nativeSession = Mockito.mock(Session.class);
 		given(nativeSession.getUserPrincipal()).willReturn(null);
@@ -83,7 +82,6 @@ public class StandardWebSocketSessionTests {
 	}
 
 	@Test
-	@SuppressWarnings("resource")
 	public void getAcceptedProtocol() {
 		String protocol = "foo";
 
@@ -99,4 +97,14 @@ public class StandardWebSocketSessionTests {
 		verifyNoMoreInteractions(nativeSession);
 	}
 
+	@Test // gh-29315
+	public void addAttributesWithNullKeyOrValue() {
+		this.attributes.put(null, "value");
+		this.attributes.put("key", null);
+		this.attributes.put("foo", "bar");
+
+		assertThat(new StandardWebSocketSession(this.headers, this.attributes, null, null).getAttributes())
+				.hasSize(1).containsEntry("foo", "bar");
+	}
+
 }