This operation adds a new Amazon Kinesis stream to your AWS account. A stream captures and transports data records that are continuously emitted from different data sources or producers . Scale-out within an Amazon Kinesis stream is explicitly supported by means of shards, which are uniquely identified groups of data records in an Amazon Kinesis stream.

You specify and control the number of shards that a stream is composed of. Each open shard can support up to 5 read transactions per second, up to a maximum total of 2 MB of data read per second. Each shard can support up to 1000 write transactions per second, up to a maximum total of 1 MB data written per second. You can add shards to a stream if the amount of data input increases and you can remove shards if the amount of data input decreases.

The stream name identifies the stream. The name is scoped to the AWS account used by the application. It is also scoped by 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, Amazon Kinesis immediately returns and sets the stream status to CREATING. After the stream is created, Amazon Kinesis 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 if 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.

Note: The default limit for an AWS account is 10 shards per stream. If you need to create a stream with more than 10 shards, contact AWS Support to increase the limit on your account.

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

CreateStream has a limit of 5 transactions per second per account.

This operation deletes a stream and all of its shards and data. You must shut down any applications that are operating on the stream before you delete the stream. If an application attempts to operate on a deleted stream, it will receive the exception ResourceNotFoundException .

If the stream is in the ACTIVE state, you can delete it. After a DeleteStream request, the specified stream is in the DELETING state until Amazon Kinesis completes the deletion.

Note: Amazon Kinesis might continue to accept data read and write operations, such as PutRecord and GetRecords, on a stream in the DELETING state until the stream deletion is complete.

When you delete a stream, any shards in that stream are also deleted.

You can use the DescribeStream operation to check the state of the stream, which is returned in StreamStatus .

DeleteStream has a limit of 5 transactions per second per account.

This operation returns the following information about the stream: the current status of the stream, the stream Amazon Resource Name (ARN), and an array of shard objects that comprise the stream. For each shard object there is information about the hash key and sequence number ranges that the shard spans, and the IDs of any earlier shards that played in a role in a MergeShards or SplitShard operation that created the shard. A sequence number is the identifier associated with every record ingested in the Amazon Kinesis stream. The sequence number is assigned by the Amazon Kinesis service when a record is put into the stream.

You can limit the number of returned shards using the Limit parameter. The number of shards in a stream may be too large to return from a single call to DescribeStream . You can detect this by using the HasMoreShards flag in the returned output. HasMoreShards is set to true when there is more data available.

If there are more shards available, you can request more shards by using the shard ID of the last shard returned by the DescribeStream request, in the ExclusiveStartShardId parameter in a subsequent request to DescribeStream . DescribeStream is a paginated operation.

DescribeStream has a limit of 10 transactions per second per account.

This operation returns one or more data records from a shard. A GetRecords operation request can retrieve up to 10 MB of data.

You specify a shard iterator for the shard that you want to read data from in the ShardIterator parameter. The shard iterator specifies the position in the shard from which you want to start reading data records sequentially. A shard iterator specifies this position using the sequence number of a data record in the shard. For more information about the shard iterator, see GetShardIterator.

GetRecords may return a partial result if the response size limit is exceeded. You will get an error, but not a partial result if the shard's provisioned throughput is exceeded, the shard iterator has expired, or an internal processing failure has occurred. Clients can request a smaller amount of data by specifying a maximum number of returned records using the Limit parameter. The Limit parameter can be set to an integer value of up to 10,000. If you set the value to an integer greater than 10,000, you will receive InvalidArgumentException .

A new shard iterator is returned by every GetRecords request in NextShardIterator , which you use in the ShardIterator parameter of the next GetRecords request. When you repeatedly read from an Amazon Kinesis stream use a GetShardIterator request to get the first shard iterator to use in your first GetRecords request and then use the shard iterator returned in NextShardIterator for subsequent reads.

GetRecords can return null for the NextShardIterator to reflect that the shard has been closed and that the requested shard iterator would never have returned more data.

If no items can be processed because of insufficient provisioned throughput on the shard involved in the request, GetRecords throws ProvisionedThroughputExceededException .

This operation returns a shard iterator in ShardIterator . The shard iterator specifies the position in the shard from which you want to start reading data records sequentially. A shard iterator specifies this position using the sequence number of a data record in a shard. A sequence number is the identifier associated with every record ingested in the Amazon Kinesis stream. The sequence number is assigned by the Amazon Kinesis service when a record is put into the stream.

You must specify the shard iterator type in the GetShardIterator request. For example, you can set the ShardIteratorType parameter to read exactly from the position denoted by a specific sequence number by using the AT_SEQUENCE_NUMBER shard iterator type, or right after the sequence number by using the AFTER_SEQUENCE_NUMBER shard iterator type, using sequence numbers returned by earlier PutRecord, GetRecords or DescribeStream requests. You can specify the shard iterator type TRIM_HORIZON in the request to cause ShardIterator to point to the last untrimmed record in the shard in the system, which is the oldest data record in the shard. Or you can point to just after the most recent record in the shard, by using the shard iterator type LATEST, so that you always read the most recent data in the shard.

Note: Each shard iterator expires five minutes after it is returned to the requester.

When you repeatedly read from an Amazon Kinesis stream use a GetShardIterator request to get the first shard iterator to to use in your first GetRecords request and then use the shard iterator returned by the GetRecords request in NextShardIterator for subsequent reads. A new shard iterator is returned by every GetRecords request in NextShardIterator , which you use in the ShardIterator parameter of the next GetRecords request.

If a GetShardIterator request is made too often, you will receive a ProvisionedThroughputExceededException . For more information about throughput limits, see the Amazon Kinesis Developer Guide .

GetShardIterator can return null for its ShardIterator to indicate that the shard has been closed and that the requested iterator will return no more data. A shard can be closed by a SplitShard or MergeShards operation.

GetShardIterator has a limit of 5 transactions per second per account per open shard.

This operation returns an array of the names of all the streams that are associated with the AWS account making the ListStreams request. A given AWS account can have many streams active at one time.

The number of streams may be too large to return from a single call to ListStreams . You can limit the number of returned streams using the Limit parameter. If you do not specify a value for the Limit parameter, Amazon Kinesis uses the default limit, which is currently 10.

You can detect if there are more streams available to list by using the HasMoreStreams flag from the returned output. If there are more streams available, you can request more streams by using the name of the last stream returned by the ListStreams request in the ExclusiveStartStreamName parameter in a subsequent request to ListStreams . The group of stream names returned by the subsequent request is then added to the list. You can continue this process until all the stream names have been collected in the list.

ListStreams has a limit of 5 transactions per second per account.

This operation returns an array of the names of all the streams that are associated with the AWS account making the ListStreams request. A given AWS account can have many streams active at one time.

The number of streams may be too large to return from a single call to ListStreams . You can limit the number of returned streams using the Limit parameter. If you do not specify a value for the Limit parameter, Amazon Kinesis uses the default limit, which is currently 10.

You can detect if there are more streams available to list by using the HasMoreStreams flag from the returned output. If there are more streams available, you can request more streams by using the name of the last stream returned by the ListStreams request in the ExclusiveStartStreamName parameter in a subsequent request to ListStreams . The group of stream names returned by the subsequent request is then added to the list. You can continue this process until all the stream names have been collected in the list.

ListStreams has a limit of 5 transactions per second per account.

This operation merges two adjacent shards in a stream and combines them into a single shard to reduce the stream's capacity to ingest and transport data. Two shards are considered adjacent if the union of the hash key ranges for the two shards form a contiguous set with no gaps. For example, if you have two shards, one with a hash key range of 276...381 and the other with a hash key range of 382...454, then you could merge these two shards into a single shard that would have a hash key range of 276...454. After the merge, the single child shard receives data for all hash key values covered by the two parent shards.

MergeShards is called when there is a need to reduce the overall capacity of a stream because of excess capacity that is not being used. The operation requires that you specify the shard to be merged and the adjacent shard for a given stream. For more information about merging shards, see the Amazon Kinesis Developer Guide .

If the stream is in the ACTIVE state, you can call MergeShards . If a stream is in CREATING or UPDATING or DELETING states, then Amazon Kinesis returns a ResourceInUseException . If the specified stream does not exist, Amazon Kinesis returns a ResourceNotFoundException .

You can use the DescribeStream operation to check the state of the stream, which is returned in StreamStatus .

MergeShards is an asynchronous operation. Upon receiving a MergeShards request, Amazon Kinesis immediately returns a response and sets the StreamStatus to UPDATING. After the operation is completed, Amazon Kinesis sets the StreamStatus to ACTIVE. Read and write operations continue to work while the stream is in the UPDATING state.

You use the DescribeStream operation to determine the shard IDs that are specified in the MergeShards request.

If you try to operate on too many streams in parallel using CreateStream, DeleteStream, MergeShards or SplitShard, you will receive a LimitExceededException .

MergeShards has limit of 5 transactions per second per account.

This operation puts a data record into an Amazon Kinesis stream from a producer. This operation must be called to send data from the producer into the Amazon Kinesis stream for real-time ingestion and subsequent processing. The PutRecord operation requires the name of the stream that captures, stores, and transports the data; a partition key; and the data blob itself. The data blob could be a segment from a log file, geographic/location data, website clickstream data, or any other data type.

The partition key is used to distribute data across shards. Amazon Kinesis segregates the data records that belong to a data stream into multiple shards, using the partition key associated with each data record to determine which shard a given data record belongs to.

Partition keys are Unicode strings, with a maximum length limit of 256 bytes. An MD5 hash function is used to map partition keys to 128-bit integer values and to map associated data records to shards using the hash key ranges of the shards. You can override hashing the partition key to determine the shard by explicitly specifying a hash value using the ExplicitHashKey parameter. For more information, see the Amazon Kinesis Developer Guide .

PutRecord returns the shard ID of where the data record was placed and the sequence number that was assigned to the data record.

Sequence numbers generally increase over time. To guarantee strictly increasing ordering, use the SequenceNumberForOrdering parameter. For more information, see the Amazon Kinesis Developer Guide .

If a PutRecord request cannot be processed because of insufficient provisioned throughput on the shard involved in the request, PutRecord throws ProvisionedThroughputExceededException .

Data records are accessible for only 24 hours from the time that they are added to an Amazon Kinesis stream.

This operation splits a shard into two new shards in the stream, to increase the stream's capacity to ingest and transport data. SplitShard is called when there is a need to increase the overall capacity of stream because of an expected increase in the volume of data records being ingested.

SplitShard can also be used when a given shard appears to be approaching its maximum utilization, for example, when the set of producers sending data into the specific shard are suddenly sending more than previously anticipated. You can also call the SplitShard operation to increase stream capacity, so that more Amazon Kinesis applications can simultaneously read data from the stream for real-time processing.

The SplitShard operation requires that you specify the shard to be split and the new hash key, which is the position in the shard where the shard gets split in two. In many cases, the new hash key might simply be the average of the beginning and ending hash key, but it can be any hash key value in the range being mapped into the shard. For more information about splitting shards, see the Amazon Kinesis Developer Guide .

You can use the DescribeStream operation to determine the shard ID and hash key values for the ShardToSplit and NewStartingHashKey parameters that are specified in the SplitShard request.

SplitShard is an asynchronous operation. Upon receiving a SplitShard request, Amazon Kinesis immediately returns a response and sets the stream status to UPDATING. After the operation is completed, Amazon Kinesis sets the stream status to ACTIVE. Read and write operations continue to work while the stream is in the UPDATING state.

You can use DescribeStream to check the status of the stream, which is returned in StreamStatus . If the stream is in the ACTIVE state, you can call SplitShard . If a stream is in CREATING or UPDATING or DELETING states, then Amazon Kinesis returns a ResourceInUseException .

If the specified stream does not exist, Amazon Kinesis returns a ResourceNotFoundException . If you try to create more shards than are authorized for your account, you receive a LimitExceededException .

Note: The default limit for an AWS account is 10 shards per stream. If you need to create a stream with more than 10 shards, contact AWS Support to increase the limit on your account.

If you try to operate on too many streams in parallel using CreateStream, DeleteStream, MergeShards or SplitShard, you will receive a LimitExceededException .

SplitShard has limit of 5 transactions per second per account.