Add support for customized Cassandra keyspace creations

[rreimann]

Using the Cluster bean from CassandraAutoConfiguration makes it quite difficult to provide a custom keyspace creation (e.g. via CreateKeyspaceSpecification).

While CassandraClusterFactoryBean#setKeyspaceCreations provides support for custom keyspace creations I couldn't find anything similar when the cluster is created via the auto-configuration.

Trying to find a workaround that doesn't duplicate existing auto-configuration code led to this ugly custom configuration...

@Configuration
@Import(CassandraDataAutoConfiguration.class)
@EnableConfigurationProperties(CassandraProperties.class)
public class CassandraCustomConfiguration {

    @Bean
    Cluster cluster(CassandraProperties properties, ObjectProvider<ClusterBuilderCustomizer> builderCustomizers) {
        CassandraAutoConfiguration cassandraAutoConfiguration = new CassandraAutoConfiguration(properties, builderCustomizers);
        Cluster cluster = cassandraAutoConfiguration.cassandraCluster();
        createKeyspace(cluster, getSimpleKeyspaceCreation());
        return cluster;
    }

    private CreateKeyspaceSpecification getSimpleKeyspaceCreation() {
        return CreateKeyspaceSpecification.createKeyspace("foo").ifNotExists(); // simplified sample
    }

    private void createKeyspace(Cluster cluster, CreateKeyspaceSpecification keyspaceCreation) {
        try (Session session = cluster.connect()) {
            CqlTemplate template = new CqlTemplate(session);
            template.execute(CreateKeyspaceCqlGenerator.toCql(keyspaceCreation));
        }
    }
}

It would be nice if the auto-configuration would provide support for keyspace creations.

[snicoll]

Thanks for the suggestion. I don't know if that's the code you are using now but importing the auto-configurations the way you do is quite unusual (and probably unnecessary) . What is wrong with getting the Cluster as a bean and creating the keyspace?

[rreimann]

Thanks for the quick response...

but importing the auto-configurations the way you do is quite unusual (and probably unnecessary)

yes I know that's why i called it "ugly" myself. The import was necessary because CassandraDataAutoConfiguration is disabled due to the Cluster bean I provide in my config.

What is wrong with getting the Cluster as a bean and creating the keyspace?

Trying that failed for me because CassandraDataAutoConfiguration#cassandraSession invokes getCluster().connect(keyspaceName) via CassandraCqlSessionFactoryBean#afterPropertiesSet which fails due to the non-existing keyspace before I have a chance to get the Cluster injected and create the keyspace.

[snicoll]

The import was necessary because CassandraDataAutoConfiguration is disabled due to the Cluster bean I provide in my config.

I don't see why it was. If you provide your own Cluster you are basically providing your opinion and Spring Boot will back off which is the advertized feature. There is a @ConditionalOnMissingBean on the cluster @Bean method so providing your own will only disable that part of the auto-config.

which fails due to the non-existing keyspace before I have a chance to get the Cluster injected and create the keyspace.

Thanks that helps.

[rreimann]

I don't see why it was. If you provide your own Cluster you are basically providing your opinion and Spring Boot will back off which is the advertized feature. There is a @ConditionalOnMissingBean on the cluster @bean method so providing your own will only disable that part of the auto-config.

You're right, my bad - there's no need for the import in prod code. I checked again and it was only a test that run in to a NoSuchBeanDefinitionException: No qualifying bean of type 'org.springframework.data.cassandra.core.CassandraOperations due to a restricted test context.

[rreimann]

@philwebb would you like to share the reason why this was declined?

[snicoll]

@rreimann because we were discussing two different topics in one issue and I guess @philwebb concluded that you found out what the problem was. But this issue is about keyspace creation so let's leave it at that from now on.