createStream method

Future<void> createStream({
  1. required int shardCount,
  2. required String streamName,
})

Creates a Kinesis data stream. A stream captures and transports data records that are continuously emitted from different data sources or producers. Scale-out within a stream is explicitly supported by means of shards, which are uniquely identified groups of data records in a stream.

You specify and control the number of shards that a stream is composed of. Each shard can support reads up to five transactions per second, up to a maximum data read total of 2 MiB per second. Each shard can support writes up to 1,000 records per second, up to a maximum data write total of 1 MiB per second. If the amount of data input increases or decreases, you can add or remove shards.

The stream name identifies the stream. The name is scoped to the AWS account used by the application. It is also scoped by AWS Region. That is, two streams in two different accounts can have the same name, and two streams in the same account, but in two different Regions, can have the same name.

CreateStream is an asynchronous operation. Upon receiving a CreateStream request, Kinesis Data Streams immediately returns and sets the stream status to CREATING. After the stream is created, Kinesis Data Streams sets the stream status to ACTIVE. You should perform read and write operations only on an ACTIVE stream.

You receive a LimitExceededException when making a CreateStream request when you try to do one of the following:

  • Have more than five streams in the CREATING state at any point in time.
  • Create more shards than are authorized for your account.
For the default shard limit for an AWS account, see Amazon Kinesis Data Streams Limits in the Amazon Kinesis Data Streams Developer Guide. To increase this limit, contact AWS Support.

You can use DescribeStream to check the stream status, which is returned in StreamStatus.

CreateStream has a limit of five transactions per second per account.

May throw ResourceInUseException. May throw LimitExceededException. May throw InvalidArgumentException.

Parameter shardCount : The number of shards that the stream will use. The throughput of the stream is a function of the number of shards; more shards are required for greater provisioned throughput.

Parameter streamName : A name to identify the stream. The stream name is scoped to the AWS account used by the application that creates the stream. It is also scoped by AWS Region. That is, two streams in two different AWS accounts can have the same name. Two streams in the same AWS account but in two different Regions can also have the same name.

Implementation

Future<void> createStream({
  required int shardCount,
  required String streamName,
}) async {
  ArgumentError.checkNotNull(shardCount, 'shardCount');
  _s.validateNumRange(
    'shardCount',
    shardCount,
    1,
    1152921504606846976,
    isRequired: true,
  );
  ArgumentError.checkNotNull(streamName, 'streamName');
  _s.validateStringLength(
    'streamName',
    streamName,
    1,
    128,
    isRequired: true,
  );
  final headers = <String, String>{
    'Content-Type': 'application/x-amz-json-1.1',
    'X-Amz-Target': 'Kinesis_20131202.CreateStream'
  };
  await _protocol.send(
    method: 'POST',
    requestUri: '/',
    exceptionFnMap: _exceptionFns,
    // TODO queryParams
    headers: headers,
    payload: {
      'ShardCount': shardCount,
      'StreamName': streamName,
    },
  );
}