Avoid cast to StatefulRedisConnection upon eager LettuceConnectionFactory initialization.

We now no longer try to cast the Lettuce connection to StatefulRedisConnection when eagerly initializing the shared connection. Instead, we now introduced another method to obtain the cluster connection.

Closes #2186

Author: mp911de

src/main/java/org/springframework/data/redis/connection/lettuce/LettuceConnectionFactory.java

@@ -438,9 +438,7 @@ public RedisClusterConnection getClusterConnection() {
 
 		RedisClusterClient clusterClient = (RedisClusterClient) client;
 
-		StatefulRedisClusterConnection<byte[], byte[]> sharedConnection = getShareNativeConnection()
-				? (StatefulRedisClusterConnection<byte[], byte[]>) getOrCreateSharedConnection().getConnection()
-				: null;
+		StatefulRedisClusterConnection<byte[], byte[]> sharedConnection = getSharedClusterConnection();
 
 		LettuceClusterTopologyProvider topologyProvider = new LettuceClusterTopologyProvider(clusterClient);
 		return doCreateLettuceClusterConnection(sharedConnection, connectionProvider, topologyProvider,
@@ -540,7 +538,12 @@ public void initConnection() {
 
 		resetConnection();
 
-		getSharedConnection();
+		if (isClusterAware()) {
+			getSharedClusterConnection();
+		} else {
+			getSharedConnection();
+		}
+
 		getSharedReactiveConnection();
 	}
 
@@ -1081,12 +1084,27 @@ public boolean isClusterAware() {
 	}
 
 	/**
-	 * @return the shared connection using {@literal byte} array encoding for imperative API use. {@literal null} if
-	 *         {@link #getShareNativeConnection() connection sharing} is disabled.
+	 * @return the shared connection using {@literal byte[]} encoding for imperative API use. {@literal null} if
+	 *         {@link #getShareNativeConnection() connection sharing} is disabled or when connected to Redis Cluster.
 	 */
 	@Nullable
 	protected StatefulRedisConnection<byte[], byte[]> getSharedConnection() {
-		return shareNativeConnection ? (StatefulRedisConnection) getOrCreateSharedConnection().getConnection() : null;
+		return shareNativeConnection && !isClusterAware()
+				? (StatefulRedisConnection) getOrCreateSharedConnection().getConnection()
+				: null;
+	}
+
+	/**
+	 * @return the shared cluster connection using {@literal byte[]} encoding for imperative API use. {@literal null} if
+	 *         {@link #getShareNativeConnection() connection sharing} is disabled or when connected to Redis
+	 *         Standalone/Sentinel/Master-Replica.
+	 * @since 2.5.7
+	 */
+	@Nullable
+	protected StatefulRedisClusterConnection<byte[], byte[]> getSharedClusterConnection() {
+		return shareNativeConnection && isClusterAware()
+				? (StatefulRedisClusterConnection) getOrCreateSharedConnection().getConnection()
+				: null;
 	}
 
 	/**

src/test/java/org/springframework/data/redis/connection/lettuce/LettuceConnectionFactoryTests.java

@@ -48,6 +48,7 @@
 import org.springframework.data.redis.connection.RedisStaticMasterReplicaConfiguration;
 import org.springframework.data.redis.connection.StringRedisConnection;
 import org.springframework.data.redis.connection.lettuce.extension.LettuceConnectionFactoryExtension;
+import org.springframework.data.redis.test.condition.EnabledOnRedisClusterAvailable;
 import org.springframework.data.redis.test.extension.LettuceTestClientResources;
 
 /**
@@ -85,7 +86,6 @@ void tearDown() {
 		factory.destroy();
 	}
 
-
 	@SuppressWarnings("rawtypes")
 	@Test
 	void testGetNewConnectionOnError() throws Exception {
@@ -462,9 +462,8 @@ void pubSubDoesNotSupportMasterReplicaConnections() {
 
 		RedisConnection connection = factory.getConnection();
 
-		assertThatThrownBy(() -> connection.pSubscribe((message, pattern) -> {
-		}, "foo".getBytes())).isInstanceOf(RedisConnectionFailureException.class)
-				.hasCauseInstanceOf(UnsupportedOperationException.class);
+		assertThatThrownBy(() -> connection.pSubscribe((message, pattern) -> {}, "foo".getBytes()))
+				.isInstanceOf(RedisConnectionFailureException.class).hasCauseInstanceOf(UnsupportedOperationException.class);
 
 		connection.close();
 		factory.destroy();
@@ -558,4 +557,44 @@ void getClientNameShouldEqualWithFactorySetting() {
 
 		connection.close();
 	}
+
+	@Test // GH-2186
+	void shouldInitializeMasterReplicaConnectionsEagerly() {
+
+		LettuceClientConfiguration configuration = LettuceClientConfiguration.builder()
+				.clientResources(LettuceTestClientResources.getSharedClientResources()).build();
+
+		RedisStaticMasterReplicaConfiguration elastiCache = new RedisStaticMasterReplicaConfiguration(
+				SettingsUtils.getHost()).node(SettingsUtils.getHost(), SettingsUtils.getPort() + 1);
+
+		LettuceConnectionFactory factory = new LettuceConnectionFactory(elastiCache, configuration);
+		factory.setEagerInitialization(true);
+		factory.afterPropertiesSet();
+
+		assertThat(factory.getSharedConnection()).isNotNull();
+		assertThat(factory.getSharedClusterConnection()).isNull();
+
+		factory.getConnection().close();
+		factory.destroy();
+	}
+
+	@Test // GH-2186
+	@EnabledOnRedisClusterAvailable
+	void shouldInitializeClusterConnectionsEagerly() {
+
+		LettuceClientConfiguration configuration = LettuceClientConfiguration.builder()
+				.clientResources(LettuceTestClientResources.getSharedClientResources()).build();
+
+		LettuceConnectionFactory factory = new LettuceConnectionFactory(SettingsUtils.clusterConfiguration(),
+				configuration);
+		factory.setEagerInitialization(true);
+		factory.afterPropertiesSet();
+
+		assertThat(factory.getSharedConnection()).isNull();
+		assertThat(factory.getSharedClusterConnection()).isNotNull();
+
+		factory.getConnection().close();
+		factory.destroy();
+	}
+
 }