How to set Spring Data Cassandra keyspace dynamically?

Question

We're using Spring Boot 1.5.10 with Spring Data for Apache Cassandra and that's all working well.

We've had a new requirement coming along where we need to connect to a different keyspace while the service is up and running.

Through the use of Spring Cloud Config Server, we can easily set the value of spring.data.cassandra.keyspace-name, however, we're not certain if there's a way that we can dynamically switch (force) the service to use this new keyspace without having to restart if first?

Any ideas or suggestions?

Answer 1

Using @RefreshScope with properties/repositories doesn't work as the keyspace is bound to the Cassandra Session bean.

Using Spring Data Cassandra 1.5 with Spring Boot 1.5 you have at least two options:

1. Declare a @RefreshScope CassandraSessionFactoryBean, see also CassandraDataAutoConfiguration. This will interrupt all Cassandra operations upon refresh and re-create all dependant beans.

2. Listen to RefreshScopeRefreshedEvent and change the keyspace via USE my-new-keyspace;. This approach is less invasive and doesn't interrupt running queries. You'd basically use an event listener.

   @Component
   class MySessionRefresh {
   
     private final Session session;
     private final Environment environment;
   
     // omitted constructors for brevity
   
     @EventListener
     @Order(Ordered.LOWEST_PRECEDENCE)
     public void handle(RefreshScopeRefreshedEvent event) {
   
       String keyspace = environment.getProperty("spring.data.cassandra.keyspace-name");
       session.execute("USE " + keyspace + ";");
     }
   }
   

With Spring Data Cassandra 2, we introduced the SessionFactory abstraction providing AbstractRoutingSessionFactory for code-controlled routing of CQL/session calls.