Project: Apache Storm (App Definition and Development / Streaming & Messaging)
File: storm-redis.md

title: Storm Redis Integration layout: documentation documentation: true Storm/Trident integration for Storm-redis uses Jedis for Redis client. use it as a maven dependency: ```xml <dependency> <groupId>org.apache.storm</groupId> <artifactId>storm-redis</artifactId> <version>${storm.version}</version> <type>jar</type> </dependency> ``` Storm-redis provides basic Bolt implementations, `RedisLookupBolt` and `RedisStoreBolt`, and `RedisFilterBolt`. As name represents its usage, `RedisLookupBolt` retrieves value from Redis using key, and `RedisStoreBolt` stores key / value to Redis, and `RedisFilterBolt` filters out tuple which key or field doesn't exist on Redis. One tuple will be matched to one key / value pair, and you can define match pattern to `TupleMapper`. You can also choose data type from `RedisDataTypeDescription` to use. Please refer `RedisDataTypeDescription.RedisDataType` to see what data types are supported. In some data types (hash and sorted set, and set if only RedisFilterBolt), it requires additional key and converted key from tuple becomes element. These interfaces are combined with `RedisLookupMapper` and `RedisStoreMapper` and `RedisFilterMapper` which fit `RedisLookupBolt` and `RedisStoreBolt`, and `RedisFilterBolt` respectively. (When you want to implement RedisFilterMapper, be sure to set declareOutputFields() to declare same fields to input stream, since FilterBolt forwards input tuples when they exist on Redis.) ```java class WordCountRedisLookupMapper implements RedisLookupMapper { private RedisDataTypeDescription description; private final String hashKey = "wordCount"; public WordCountRedisLookupMapper() { description = new RedisDataTypeDescription( RedisDataTypeDescription.RedisDataType.HASH, hashKey); } @Override public List<Values> toTuple(ITuple input, Object value) { String member = getKeyFromTuple(input); List<Values> values = Lists.newArrayList(); values.add(new Values(member, value)); return values; } @Override public void declareOutputFields(OutputFieldsDeclarer declarer) { declarer.declare(new Fields("wordName", "count")); } @Override public RedisDataTypeDescription getDataTypeDescription() { return description; } @Override public String getKeyFromTuple(ITuple tuple) { return tuple.getStringByField("word"); } @Override public String getValueFromTuple(ITuple tuple) { return null; } } ``` ```java JedisPoolConfig poolConfig = new JedisPoolConfig.Builder() .setHost(host).setPort(port).build(); RedisLookupMapper lookupMapper = new WordCountRedisLookupMapper(); RedisLookupBolt lookupBolt = new RedisLookupBolt(poolConfig, lookupMapper); ``` ```java class BlacklistWordFilterMapper implements RedisFilterMapper { private RedisDataTypeDescription description; private final String setKey = "blacklist"; public BlacklistWordFilterMapper() { description = new RedisDataTypeDescription( RedisDataTypeDescription.RedisDataType.SET, setKey); } @Override public void declareOutputFields(OutputFieldsDeclarer declarer) { declarer.declare(new Fields("word", "count")); } @Override public RedisDataTypeDescription getDataTypeDescription() { return description; } @Override public String getKeyFromTuple(ITuple tuple) { return tuple.getStringByField("word"); } @Override public String getValueFromTuple(ITuple tuple) { return null; } } ``` ```java JedisPoolConfig poolConfig = new JedisPoolConfig.Builder()

RedisFilterMapper filterMapper = new BlacklistWordFilterMapper(); RedisFilterBolt filterBolt = new RedisFilterBolt(poolConfig, filterMapper); ``` ```java class WordCountStoreMapper implements RedisStoreMapper { private RedisDataTypeDescription description; private final String hashKey = "wordCount"; public WordCountStoreMapper() { description = new RedisDataTypeDescription( RedisDataTypeDescription.RedisDataType.HASH, hashKey); } @Override public RedisDataTypeDescription getDataTypeDescription() { return description; } @Override public String getKeyFromTuple(ITuple tuple) { return tuple.getStringByField("word"); } @Override public String getValueFromTuple(ITuple tuple) { return tuple.getStringByField("count"); } } ``` ```java JedisPoolConfig poolConfig = new JedisPoolConfig.Builder() .setHost(host).setPort(port).build(); RedisStoreMapper storeMapper = new WordCountStoreMapper(); RedisStoreBolt storeBolt = new RedisStoreBolt(poolConfig, storeMapper); ``` If your scenario doesn't fit ```RedisStoreBolt``` and ```RedisLookupBolt``` and ```RedisFilterBolt```, storm-redis also provides ```AbstractRedisBolt``` to let you extend and apply your business logic. ```java public static class LookupWordTotalCountBolt extends AbstractRedisBolt { private static final Logger LOG = LoggerFactory.getLogger(LookupWordTotalCountBolt.class); private static final Random RANDOM = new Random(); public LookupWordTotalCountBolt(JedisPoolConfig config) { super(config); } public LookupWordTotalCountBolt(JedisClusterConfig config) { super(config); } @Override public void execute(Tuple input) { JedisCommands jedisCommands = null; try { jedisCommands = getInstance(); String wordName = input.getStringByField("word"); String countStr = jedisCommands.get(wordName); if (countStr != null) { int count = Integer.parseInt(countStr); this.collector.emit(new Values(wordName, count)); // print lookup result with low probability if(RANDOM.nextInt(1000) > 995) { LOG.info("Lookup result - word : " + wordName + " / count : " + count); } } else { // skip LOG.warn("Word not found in Redis - word : " + wordName); } } finally { if (jedisCommands != null) { returnInstance(jedisCommands); } this.collector.ack(input); } } @Override public void declareOutputFields(OutputFieldsDeclarer declarer) { // wordName, count declarer.declare(new Fields("wordName", "count")); } } ``` RedisState and RedisMapState, which provide Jedis interface just for single redis. RedisClusterState and RedisClusterMapState, which provide JedisCluster interface, just for redis cluster. RedisState ```java JedisPoolConfig poolConfig = new JedisPoolConfig.Builder() .setHost(redisHost).setPort(redisPort) .build(); RedisStoreMapper storeMapper = new WordCountStoreMapper(); RedisLookupMapper lookupMapper = new WordCountLookupMapper(); RedisState.Factory factory = new RedisState.Factory(poolConfig); TridentTopology topology = new TridentTopology(); Stream stream = topology.newStream("spout1", spout); stream.partitionPersist(factory, fields, new RedisStateUpdater(storeMapper).withExpire(86400000), new Fields()); TridentState state = topology.newStaticState(factory); stream = stream.stateQuery(state, new Fields("word"), new RedisStateQuerier(lookupMapper), new Fields("columnName","columnValue")); ``` RedisClusterState ```java Set<InetSocketAddress> nodes = new HashSet<InetSocketAddress>(); for (String hostPort : redisHostPort.split(",")) { String[] host_port = hostPort.split(":"); nodes.add(new InetSocketAddress(hostport[0], Integer.valueOf(hostport[1]))); } JedisClusterConfig clusterConfig = new JedisClusterConfig.Builder().setNodes(nodes) .build(); RedisStoreMapper storeMapper = new WordCountStoreMapper(); RedisLookupMapper lookupMapper = new WordCountLookupMapper(); RedisClusterState.Factory factory = new RedisClusterState.Factory(clusterConfig); TridentTopology topology = new TridentTopology(); Stream stream = topology.newStream("spout1", spout); stream.partitionPersist(factory, fields, new RedisClusterStateUpdater(storeMapper).withExpire(86400000), new Fields()); TridentState state = topology.newStaticState(factory); stream = stream.stateQuery(state, new Fields("word"), new RedisClusterStateQuerier(lookupMapper), new Fields("columnName","columnValue")); ```