AWS supports the following Ruby runtimes:

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Name | Identifier | SDK for Ruby | Operating system
-- | -- | -- | --
Ruby 2.7 | ruby2.7 | 3.0.1 | Amazon Linux 2
Ruby 2.5 | ruby2.5 | 3.0.1 | Amazon Linux

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Currently, `localstack/lambda` only contains the `ruby2.5` tag. Will the 2.7 runtime be supported in the (near) future?
self.assertEqual(response['DestinationConfig'], destination_config)
        
        response = lambda_client.delete_function_event_invoke_config(
            FunctionName=function_name)
        lambda_client.delete_function(FunctionName=function_name)
    def test_event_source_mapping_default_batch_size(self):
        function_name = 'lambda_func-{}'.format(short_uid())
        queue_name_1 = 'queue-{}-1'.format(short_uid())
        queue_name_2 = 'queue-{}-2'.format(short_uid())
        ddb_table = 'ddb_table-{}'.format(short_uid())
        testutil.create_lambda_function(
            handler_file=TEST_LAMBDA_ECHO_FILE,
            func_name=function_name,
            runtime=LAMBDA_RUNTIME_PYTHON36
        )
        lambda_client = aws_stack.connect_to_service('lambda')
        sqs_client = aws_stack.connect_to_service('sqs')
        queue_url_1 = sqs_client.create_queue(QueueName=queue_name_1)['QueueUrl']
        queue_arn_1 = aws_stack.sqs_queue_arn(queue_name_1)
        rs = lambda_client.create_event_source_mapping(
            EventSourceArn=queue_arn_1, FunctionName=function_name)
        self.assertEqual(rs['BatchSize'], BATCH_SIZE_RANGES['sqs'][0])
        uuid = rs['UUID']
        try:
            
            lambda_client.update_event_source_mapping(
                UUID=uuid,
                FunctionName=function_name,
                BatchSize=BATCH_SIZE_RANGES['sqs'][1] + 1
            )