From 0141787d0895543096c93deec60cd5bdecf21db2 Mon Sep 17 00:00:00 2001
From: Sergey Matvienko <smatvienko@thingsboard.io>
Date: Fri, 17 Jun 2022 19:15:44 +0300
Subject: [PATCH] RedisTbTransactionalCache - redis cluster watch support by a
 single key

---
 .../cache/RedisTbTransactionalCache.java      | 37 +++++++++++++++----
 1 file changed, 30 insertions(+), 7 deletions(-)

diff --git a/common/cache/src/main/java/org/thingsboard/server/cache/RedisTbTransactionalCache.java b/common/cache/src/main/java/org/thingsboard/server/cache/RedisTbTransactionalCache.java
index ed39bf3716..2cf326905c 100644
--- a/common/cache/src/main/java/org/thingsboard/server/cache/RedisTbTransactionalCache.java
+++ b/common/cache/src/main/java/org/thingsboard/server/cache/RedisTbTransactionalCache.java
@@ -21,20 +21,27 @@ import org.springframework.cache.support.NullValue;
 import org.springframework.data.redis.connection.RedisConnection;
 import org.springframework.data.redis.connection.RedisConnectionFactory;
 import org.springframework.data.redis.connection.RedisStringCommands;
+import org.springframework.data.redis.connection.jedis.JedisClusterConnection;
+import org.springframework.data.redis.connection.jedis.JedisConnection;
 import org.springframework.data.redis.core.types.Expiration;
 import org.springframework.data.redis.serializer.RedisSerializer;
 import org.springframework.data.redis.serializer.StringRedisSerializer;
+import redis.clients.jedis.Jedis;
+import redis.clients.jedis.JedisPool;
+import redis.clients.jedis.util.JedisClusterCRC16;
 
 import java.io.Serializable;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
+import java.util.Optional;
 import java.util.concurrent.TimeUnit;
 
 @Slf4j
 public abstract class RedisTbTransactionalCache<K extends Serializable, V extends Serializable> implements TbTransactionalCache<K, V> {
 
     private static final byte[] BINARY_NULL_VALUE = RedisSerializer.java().serialize(NullValue.INSTANCE);
+    static final JedisPool MOCK_POOL = new JedisPool(); //non-null pool required for JedisConnection to trigger closing jedis connection
 
     @Getter
     private final String cacheName;
@@ -53,12 +60,12 @@ public abstract class RedisTbTransactionalCache<K extends Serializable, V extend
         this.connectionFactory = connectionFactory;
         this.valueSerializer = valueSerializer;
         this.evictExpiration = Expiration.from(configuration.getEvictTtlInMs(), TimeUnit.MILLISECONDS);
-        if (cacheSpecsMap.getSpecs() != null && cacheSpecsMap.getSpecs().get(cacheName) != null) {
-            CacheSpecs cacheSpecs = cacheSpecsMap.getSpecs().get(cacheName);
-            this.cacheTtl = Expiration.from(cacheSpecs.getTimeToLiveInMinutes(), TimeUnit.MINUTES);
-        } else {
-            this.cacheTtl = Expiration.persistent();
-        }
+        this.cacheTtl = Optional.ofNullable(cacheSpecsMap)
+                .map(CacheSpecsMap::getSpecs)
+                .map(x -> x.get(cacheName))
+                .map(CacheSpecs::getTimeToLiveInMinutes)
+                .map(t -> Expiration.from(t, TimeUnit.MINUTES))
+                .orElseGet(Expiration::persistent);
     }
 
     @Override
@@ -130,8 +137,24 @@ public abstract class RedisTbTransactionalCache<K extends Serializable, V extend
         return new RedisTbCacheTransaction<>(this, connection);
     }
 
+    RedisConnection getConnection(byte[] rawKey) {
+        RedisConnection connection = connectionFactory.getClusterConnection();
+        if (!(connection instanceof JedisClusterConnection)) {
+            return connection;
+        }
+
+        int slotNum = JedisClusterCRC16.getSlot(rawKey);
+        Jedis jedis = ((JedisClusterConnection) connection).getNativeConnection().getConnectionFromSlot(slotNum);
+
+        JedisConnection jedisConnection = new JedisConnection(jedis, MOCK_POOL, jedis.getDB());
+        jedisConnection.setConvertPipelineAndTxResults(connectionFactory.getConvertPipelineAndTxResults());
+
+        return jedisConnection;
+    }
+
     private RedisConnection watch(byte[][] rawKeysList) {
-        var connection = connectionFactory.getConnection();
+        //TODO process keys only on suitable slot connection, see getConnection(byte[] rawKey)
+        RedisConnection connection = getConnection(rawKeysList[0]);
         try {
             connection.watch(rawKeysList);
             connection.multi();