For Kinesis, it seems to be, that AWS organizes its folders on S3 like: "prefix/2019/02/09/13/kinesis-stream-name-2019-02-09-10-02-32-db1db7a9-c484-40d1-b7ec-7651a55e4677"

The date in the path is UTC-time, the date in the file name is the UTC-time of the first received byte in the Kinesis stream for the specific file. This is the default behavior, so it would be nice to implement it in localstack.
import json
import time
import base64
import logging
import unittest
from datetime import datetime, timedelta
from nose.tools import assert_raises
from localstack.utils import testutil
from localstack.utils.common import (
    load_file, short_uid, clone, to_bytes, to_str, run_safe, retry)
from localstack.services.awslambda.lambda_api import LAMBDA_RUNTIME_PYTHON27
from localstack.utils.kinesis import kinesis_connector
from localstack.utils.aws import aws_stack
from .lambdas import lambda_integration
from .test_lambda import TEST_LAMBDA_PYTHON, TEST_LAMBDA_LIBS
TEST_STREAM_NAME = lambda_integration.KINESIS_STREAM_NAME
TEST_LAMBDA_SOURCE_STREAM_NAME = 'test_source_stream'
TEST_TABLE_NAME = 'test_stream_table'
TEST_LAMBDA_NAME_DDB = 'test_lambda_ddb'
TEST_LAMBDA_NAME_STREAM = 'test_lambda_stream'
TEST_LAMBDA_NAME_QUEUE = 'test_lambda_queue'
TEST_FIREHOSE_NAME = 'test_firehose'
TEST_BUCKET_NAME = lambda_integration.TEST_BUCKET_NAME
TEST_TOPIC_NAME = 'test_topic'
TEST_TAGS = [{'Key': 'MyTag', 'Value': 'Value'}]
TEST_CHAIN_STREAM1_NAME = 'test_chain_stream_1'
TEST_CHAIN_STREAM2_NAME = 'test_chain_stream_2'
TEST_CHAIN_LAMBDA1_NAME = 'test_chain_lambda_1'