DynamoDB state repository

DynamoDB is a fully managed no-sql database available on Amazon AWS that can be easily configured to use as a state repository for togglz.

To use DynamoDB as a state repository with togglz, you must provision a table in the AWS.

To do this from the command line (change your table name out for the one you want to use):

aws dynamodb create-table --table-name YOUR_TABLE_NAME \
 --region=us-west-1 \
 --attribute-definitions AttributeName=featureName,AttributeType=S \
 --key-schema AttributeName=featureName,KeyType=HASH \
 --provisioned-throughput ReadCapacityUnits=5,WriteCapacityUnits=5

Then create a state repository with togglz:

For example, using it in combination with the spring-boot autoconfiguration you only need to provide the StateRepository instance - which relies on being passed in a configured AmazonDynamoDBClient instance

    @Bean
    AWSCredentials awsCredentials() {
        return new InstanceProfileCredentialsProvider().getCredentials();
    }
   
    @Bean
    public AmazonDynamoDBClient dynamoDBClient(AWSCredentials credentials) {
        return new AmazonDynamoDBClient(credentials);
    }
   
    @Bean
    public DynamoDBStateRepository dynamoDBStateRepository(AmazonDynamoDBClient amazonDynamoDBClient) {
        return new DynamoDBStateRepository.DynamoDBStateRepositoryBuilder(amazonDynamoDBClient).withStateStoredInTable("togglz").build();
    }

Caching

To decrease reads from the dynamo tables, you can wrap the state repository with a caching one - like this example which caches for 30 seconds:

   @Bean
   public StateRepository stateRepository(AmazonDynamoDBClient amazonDynamoDBClient) {
       DynamoDBStateRepository dynamoDBStateRepository = new DynamoDBStateRepository.DynamoDBStateRepositoryBuilder(amazonDynamoDBClient).withStateStoredInTable("togglz").build();
       return new CachingStateRepository(dynamoDBStateRepository, 30, TimeUnit.SECONDS);
   }