From e7709609927dadd110bf567f4ef54115ac535239 Mon Sep 17 00:00:00 2001
From: Burak Karahan <burak.karahan@nttdata.com>
Date: Fri, 30 Aug 2024 13:28:53 -0400
Subject: [PATCH] TCVP-3037: Added functionality to enable adaptive topology
 refreshing for Redis through 'ClusterTopologyRefreshOptions' in Lettuce to
 configure topology refreshing based on certain triggers such as 'moved
 redirect' and 'cannot reconnect'

---
 src/backend/oracle-data-api/pom.xml           |  4 ++++
 .../tco/oracledataapi/config/RedisConfig.java | 23 ++++++++++++++++++-
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/src/backend/oracle-data-api/pom.xml b/src/backend/oracle-data-api/pom.xml
index e2f8ff26b..a80a4f022 100644
--- a/src/backend/oracle-data-api/pom.xml
+++ b/src/backend/oracle-data-api/pom.xml
@@ -86,6 +86,10 @@
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-data-redis</artifactId>
 		</dependency>
+		<dependency>
+		    <groupId>io.lettuce</groupId>
+		    <artifactId>lettuce-core</artifactId>
+		</dependency>
 
 		<!-- JPA dependencies -->
 		<dependency>
diff --git a/src/backend/oracle-data-api/src/main/java/ca/bc/gov/open/jag/tco/oracledataapi/config/RedisConfig.java b/src/backend/oracle-data-api/src/main/java/ca/bc/gov/open/jag/tco/oracledataapi/config/RedisConfig.java
index d5e9c9bf2..cb5836ba6 100644
--- a/src/backend/oracle-data-api/src/main/java/ca/bc/gov/open/jag/tco/oracledataapi/config/RedisConfig.java
+++ b/src/backend/oracle-data-api/src/main/java/ca/bc/gov/open/jag/tco/oracledataapi/config/RedisConfig.java
@@ -1,5 +1,7 @@
 package ca.bc.gov.open.jag.tco.oracledataapi.config;
 
+import java.time.Duration;
+
 import org.apache.commons.lang3.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -9,9 +11,13 @@
 import org.springframework.data.redis.connection.RedisClusterConfiguration;
 import org.springframework.data.redis.connection.RedisSentinelConfiguration;
 import org.springframework.data.redis.connection.RedisStandaloneConfiguration;
+import org.springframework.data.redis.connection.lettuce.LettuceClientConfiguration;
 import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;
 import org.springframework.util.CollectionUtils;
 
+import io.lettuce.core.cluster.ClusterClientOptions;
+import io.lettuce.core.cluster.ClusterTopologyRefreshOptions;
+
 @Configuration
 public class RedisConfig {
 
@@ -45,7 +51,22 @@ else if (redisProperties.getCluster() != null && !CollectionUtils.isEmpty(redisP
 			if(redisProperties.getCluster().getMaxRedirects() != null)
 				config.setMaxRedirects(redisProperties.getCluster().getMaxRedirects());
 			
-			return new LettuceConnectionFactory(config);
+			// Enable adaptive topology refreshing
+			ClusterClientOptions clientOptions = ClusterClientOptions.builder()
+				    .topologyRefreshOptions(ClusterTopologyRefreshOptions.builder()
+			    		// The MOVED_REDIRECT trigger causes a topology refresh when the client receives a MOVED redirect from a Redis server.
+			            // The PERSISTENT_RECONNECTS trigger causes a topology refresh when the client cannot reconnect to a Redis server for a certain period of time.
+				        .enableAdaptiveRefreshTrigger(ClusterTopologyRefreshOptions.RefreshTrigger.MOVED_REDIRECT, ClusterTopologyRefreshOptions.RefreshTrigger.PERSISTENT_RECONNECTS)
+				        // If a topology refresh is triggered, the client will wait for this period of time before triggering another topology refresh.
+				        .adaptiveRefreshTriggersTimeout(Duration.ofSeconds(30)) // default is 30 seconds
+				        .build())
+				    .build();
+
+	        LettuceClientConfiguration clientConfig = LettuceClientConfiguration.builder()
+	                .clientOptions(clientOptions)
+	                .build();
+
+	        return new LettuceConnectionFactory(config, clientConfig);
 		}
 		// Standalone mode (for local development)
 		else {