Returns information about a stream, including the current status of the stream, its Amazon Resource Name (ARN), the composition of its shards, and its corresponding DynamoDB table.
You can call DescribeStream at a maximum rate of 10 times per second. Each shard in the stream has a SequenceNumberRange associated with it.
If the SequenceNumberRange has a StartingSequenceNumber but no EndingSequenceNumber, then the shard is still open (able to receive more stream records). If both StartingSequenceNumber and EndingSequenceNumber are present, then that shard is closed and can no longer receive more data.