configuration.md

Configuration

Customize SDK behavior by overriding createConfiguration() in your handler:

public class OrderProcessor extends DurableHandler<Order, OrderResult> {

    @Override
    protected DurableConfig createConfiguration() {
        // Custom Lambda client with connection pooling
        var lambdaClientBuilder = LambdaClient.builder()
            .httpClient(ApacheHttpClient.builder()
                .maxConnections(50)
                .connectionTimeout(Duration.ofSeconds(30))
                .build());

        return DurableConfig.builder()
            .withLambdaClientBuilder(lambdaClientBuilder)
            .withSerDes(new MyCustomSerDes())           // Custom serialization
            .withExecutorService(Executors.newFixedThreadPool(10))  // Custom thread pool
            .withLoggerConfig(LoggerConfig.withReplayLogging())     // Enable replay logs
            .build();
    }

    @Override
    protected OrderResult handleRequest(Order order, DurableContext ctx) {
        // Your handler logic
    }
}

Option	Description	Default
withLambdaClientBuilder()	Custom AWS Lambda client	Auto-configured Lambda client
withSerDes()	Serializer for step results	Jackson with default settings
withExecutorService()	Thread pool for user-defined operations	Cached daemon thread pool
withLoggerConfig()	Logger behavior configuration	Suppress logs during replay
withPollingStrategy()	Backend polling strategy	Exponential backoff: 1s base, 2x rate, FULL jitter, 10s max
withCheckpointDelay()	How often the SDK checkpoints updates	Duration.ofSeconds(0) (as soon as possible)

The withExecutorService() option configures the thread pool used for running user-defined operations. Internal SDK coordination (checkpoint batching, polling) runs on an SDK-managed thread pool.