private CompletableFuture<InvokeResponse> callLambda(InvocationType type, IN input) { log.debug("calling '{}' as {} with payload: {}", functionName, type, input); ByteBuffer payload = serialize(input); InvokeRequest request = InvokeRequest.builder() .functionName(functionName) .invocationType(type) .payload(payload) .build(); return lambda.invoke(request); }