Micronaut Cassandra Configuration

Provides integration between Micronaut and Cassandra

Version:

1 Introduction

The micronaut-cassandra module includes support for integrating Micronaut services with Cassandra.

Release History

2.0.0

Upgraded cassandra driver to 4.4.0 from 3.1.0
Micronaut 1.3.x minimum version

Migrating from 1.2.X to 2.X.X

The Datastax 4.4.0 drive renames a lot of fields so these properties will need to be migrated over. Individuals that wish to use their existing configuration will have to stay on 1.2.X.

cassandra.*.contactPoint and cassandra.*.port are passed to cassandra.*.basic.contact-points where contact-points is a list of strings in the format <host>:<port>
cassandra.*.MaxSchemaAgreementWaitSeconds → cassandra.*.advanced.control-connection.schema-agreement.timeout
cassandra.*.ssl → cassandra.*.advanced.ssl-engine-factory = DefaultSslEngineFactory
cassandra.*.clusterName → cassandra.*.basic.session-name

2 Setting up Cassandra

Using the CLI

If you are creating your project using the Micronaut CLI, supply the cassandra feature to include Cassandra configuration in your project:

$ mn create-app my-app --features cassandra

To enable the Cassandra configuration, add the following dependency to your application:

implementation("io.micronaut.configuration:micronaut-cassandra:2.0.0")

<dependency>
    <groupId>io.micronaut.configuration</groupId>
    <artifactId>micronaut-cassandra</artifactId>
    <version>2.0.0</version>
</dependency>

Micronaut supports Cassandra configuration by using the Datastax Java Driver. Configuration values can be supplied a property source such as below. The property name is derived from the builder methods in CqlSessionBuilder. Micronaut will create a CqlSession bean. This bean can be then injected into any other Micronaut bean.

Supply Single Configuration

cassandra:
  default:
    advanced:
      metadata:
        schema:
          enabled: false
    basic:
      contact-points:
        - "127.0.0.1:9042"
        - "127.0.0.2:8042"
      load-balancing-policy:
        local-datacenter: datacenter1

Multiple Cluster instances can be configured as follows:

Supply Multiple Configuration

cassandra:
  default:
    advanced:
      metadata:
        schema:
          enabled: false
    basic:
      contact-points:
        - "127.0.0.1:9042"
      load-balancing-policy:
        local-datacenter: datacenter1
  secondary:
    advanced:
      metadata:
        schema:
          enabled: false
    basic:
      contact-points:
        - "127.0.0.1:9043"
      load-balancing-policy:
        local-datacenter: datacenter2

3 Additional Notes

The Datastax Cassandra driver is configured using lightbend/config under the field datastax-java-driver.\*.

The equivalent bean created for micronaut is mapped under the cassandra... fields provided in your application.conf, but the bean will fallback on the datastax-java-driver.\* values if they are present.

These config values are provided to the CqlSession under the hood. Datastax does not provide a class that maps to all the various possible config keys, but a full list of values that can be provided can be found in the DefaultDriverOption enum.

datastax configuration under lightbend/config - application.conf

datastax-java-driver {
    basic {
        contact-points = [ "1.2.3.4:9042", "5.6.7.8:9042" ]
        load-balancing-policy.local-datacenter = datacenter1
    }
}

micronaut bean configuration - application.yml

cassandra:
  default:
    basic:
      contact-points:
        - "127.0.0.1:9042"
        - "5.6.7.8:9042"
      load-balancing-policy:
        local-datacenter: datacenter1

4 Repository

You can find the source code of this project in this repository:

https://github.com/micronaut-projects/micronaut-cassandra