Remove unnecessary Redis commands in RedisIndexedSessionRepository#save

See: #1331

Author: vpavic

spring-session-data-redis/src/integration-test/java/org/springframework/session/data/redis/RedisIndexedSessionRepositoryITests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2019 the original author or authors.
+ * Copyright 2014-2020 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.
@@ -18,7 +18,6 @@
 
 import java.nio.charset.StandardCharsets;
 import java.util.Map;
-import java.util.Set;
 import java.util.UUID;
 
 import org.junit.jupiter.api.BeforeEach;
@@ -135,22 +134,6 @@ void saves() throws InterruptedException {
 				.isEqualTo(expectedAttributeValue);
 	}
 
-	@Test
-	void removeAttributeRemovedAttributeKey() {
-		RedisSession toSave = this.repository.createSession();
-		toSave.setAttribute("a", "b");
-		this.repository.save(toSave);
-
-		toSave.removeAttribute("a");
-		this.repository.save(toSave);
-
-		String id = toSave.getId();
-		String key = "RedisIndexedSessionRepositoryITests:sessions:" + id;
-
-		Set<Map.Entry<Object, Object>> entries = this.redis.boundHashOps(key).entries().entrySet();
-		assertThat(entries).extracting(Map.Entry::getKey).doesNotContain("sessionAttr:a");
-	}
-
 	@Test
 	void putAllOnSingleAttrDoesNotRemoveOld() {
 		RedisSession toSave = this.repository.createSession();

spring-session-data-redis/src/main/java/org/springframework/session/data/redis/RedisIndexedSessionRepository.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2019 the original author or authors.
+ * Copyright 2014-2020 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.
@@ -792,8 +792,7 @@ private void saveDelta() {
 				return;
 			}
 			String sessionId = getId();
-			BoundHashOperations<Object, Object, Object> boundHashOperations = getSessionBoundHashOperations(sessionId);
-			boundHashOperations.putAll(this.delta);
+			getSessionBoundHashOperations(sessionId).putAll(this.delta);
 			String principalSessionKey = getSessionAttrNameKey(
 					FindByIndexNameSessionRepository.PRINCIPAL_NAME_INDEX_NAME);
 			String securityPrincipalSessionKey = getSessionAttrNameKey(SPRING_SECURITY_CONTEXT);
@@ -812,11 +811,6 @@ private void saveDelta() {
 							.add(sessionId);
 				}
 			}
-			for (final Map.Entry<String, Object> attribute : this.delta.entrySet()) {
-				if (attribute.getValue() == null) {
-					boundHashOperations.delete(attribute.getKey());
-				}
-			}
 
 			this.delta = new HashMap<>(this.delta.size());