trident-cassandra
Cassandra state implementation for Twitter Storm Trident API.
All 3 state types are working good (non-transactional, opaque-transactional and transactional).
Maven
https://clojars.org/trident-cassandra
<dependency>
<groupId>trident-cassandra</groupId>
<artifactId>trident-cassandra</artifactId>
<!-- for storm 0.8.1 use wip1 version -->
<version>0.0.1-wip2</version>
</dependency>Usage
Use static factory methods in trident.cassandra.CassandraState.
Word count topology sample:
StateFactory cassandraStateFactory = CassandraState.transactional("localhost");
TridentState wordCounts = topology.newStream("spout1", spout)
.each(new Fields("sentence"), new Split(), new Fields("word"))
.groupBy(new Fields("word"))
.persistentAggregate(cassandraStateFactory, new Count(), new Fields("count"))
.parallelismHint(6);CassandraState.Options, that could be passed to factory methods:
public static class Options<T> implements Serializable {
public int localCacheSize = 5000;
public String globalKey = "$__GLOBAL_KEY__$";
public Serializer<T> serializer = null;
public String clusterName = "trident-state";
public int replicationFactor = 1;
public String keyspace = "test";
public String columnFamily = "column_family";
public String rowKey = "row_key";
}License
Copyright (C) 2012 Sergey Lukjanov
Distributed under the Eclipse Public License, the same as Clojure.
(License is under discussions, it may be changed soon)