Configuring Data Persistence With Cassandra

WSO2 DAS supports Apache Cassandra for its underlying Data Access Layer (DAL). In order to use the Cassandra DAL component, a pre-configured installation of Apache Cassandra (2.0.x or 2.1.x version) is required. The Cassandra implementation for the DAS DAL contains the implementations of Analytics Record Store.

The following sections describe both implementations of the Cassandra DAL component.

The Cassandra datasource does not support pagination or record count.

Enabling the Cassandra datasource provider

In order to use Cassandra as the record store, the Cassandra datasource provider should be enabled as follows.

Open the <DAS_HOME>/repository/conf/datasources/analytics-datasources.xml file. The Cassandra datasource provider is commented out by default as shown below.
```

```

Uncomment the Cassandra datasource provider as shown below.

<provider>org.wso2.carbon.datasource.reader.cassandra.CassandraDataSourceReader</provider>

Configurations for the Analytics Record Store

To configure Cassandra as the underlying datasource implementation for the Analytics Record Store, specify the Cassandra configurations in the <DAS_HOME>/repository/conf/analytics/analytics-config.xml file as shown in the example below.

<analytics-record-store name="EVENT_STORE">
    <implementation>org.wso2.carbon.analytics.datasource.cassandra.CassandraAnalyticsRecordStore</implementation>
    <properties>
        <!-- the data source name mentioned in data sources configuration -->
        <property name="datasource">WSO2_ANALYTICS_DS_CASSANDRA</property>
    </properties>
</analytics-record-store>

The properties of the above configuration are described below.

Property	Description
<implementation>	The implementation class of the Analytics Record Store relevant for Cassandra, which is `org.wso2.carbon.analytics.datasource.cassandra.CassandraAnalyticsRecordStore`.
<property name="datasource">	The Carbon datasource name of the `CASSANDRA` type that is used to find the associated Cassandra data source.

Configuring the datasources

Change the configurations of the WSO2_ANALYTICS_EVENT_STORE_DB datasource in the <DAS_HOME>/repository/conf/datasources/analytics-datasources.xml file accordingly. For information on the datasource configurations, see Configuring a Cassandra Datasource.