Network.AWS.Kinesis.GetShardIterator

Gets an Amazon Kinesis shard iterator. A shard iterator expires five minutes after it is returned to the requester.

A shard iterator specifies the shard position from which to start reading data records sequentially. The position is specified using the sequence number of a data record in a shard. A sequence number is the identifier associated with every record ingested in the stream, and is assigned when a record is put into the stream. Each stream has one or more shards.

You must specify the shard iterator type. 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 calls to PutRecord, PutRecords, GetRecords, or DescribeStream. In the request, you can specify the shard iterator type AT_TIMESTAMP to read records from an arbitrary point in time, TRIM_HORIZON to cause ShardIterator to point to the last untrimmed record in the shard in the system (the oldest data record in the shard), or LATEST so that you always read the most recent data in the shard.

When you read repeatedly from a stream, use a GetShardIterator request to get the first shard iterator for use in your first GetRecords request and for subsequent reads use the shard iterator returned by the GetRecords request in NextShardIterator. 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 receive a ProvisionedThroughputExceededException. For more information about throughput limits, see GetRecords, and Streams Limits in the Amazon Kinesis Streams Developer Guide.

If the shard is closed, GetShardIterator returns a valid iterator for the last sequence number of the shard. Note that a shard can be closed as a result of using SplitShard or MergeShards.

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

Creating a Request

getShardIterator

Arguments

:: Text

gsiStreamName

-> Text

gsiShardId

-> ShardIteratorType

gsiShardIteratorType

-> GetShardIterator

Creates a value of GetShardIterator with the minimum fields required to make a request.

Use one of the following lenses to modify other fields as desired:

• gsiStartingSequenceNumber
• gsiTimestamp
• gsiStreamName
• gsiShardId
• gsiShardIteratorType

data GetShardIterator

Represents the input for GetShardIterator.

See: getShardIterator smart constructor.

Instances

Eq GetShardIterator

Methods

(==) :: GetShardIterator -> GetShardIterator -> Bool

(/=) :: GetShardIterator -> GetShardIterator -> Bool

Data GetShardIterator

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> GetShardIterator -> c GetShardIterator

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c GetShardIterator

toConstr :: GetShardIterator -> Constr

dataTypeOf :: GetShardIterator -> DataType

dataCast1 :: Typeable (* -> *) t => (forall d. Data d => c (t d)) -> Maybe (c GetShardIterator)

dataCast2 :: Typeable (* -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c GetShardIterator)

gmapT :: (forall b. Data b => b -> b) -> GetShardIterator -> GetShardIterator

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> GetShardIterator -> r

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> GetShardIterator -> r

gmapQ :: (forall d. Data d => d -> u) -> GetShardIterator -> [u]

gmapQi :: Int -> (forall d. Data d => d -> u) -> GetShardIterator -> u

gmapM :: Monad m => (forall d. Data d => d -> m d) -> GetShardIterator -> m GetShardIterator

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> GetShardIterator -> m GetShardIterator

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> GetShardIterator -> m GetShardIterator

Read GetShardIterator

Methods

readsPrec :: Int -> ReadS GetShardIterator

readList :: ReadS [GetShardIterator]

readPrec :: ReadPrec GetShardIterator

readListPrec :: ReadPrec [GetShardIterator]

Show GetShardIterator

Methods

showsPrec :: Int -> GetShardIterator -> ShowS

show :: GetShardIterator -> String

showList :: [GetShardIterator] -> ShowS

Generic GetShardIterator

Associated Types

type Rep GetShardIterator :: * -> *

Methods

from :: GetShardIterator -> Rep GetShardIterator x

to :: Rep GetShardIterator x -> GetShardIterator

Hashable GetShardIterator

Methods

hashWithSalt :: Int -> GetShardIterator -> Int

hash :: GetShardIterator -> Int

ToJSON GetShardIterator

Methods

toJSON :: GetShardIterator -> Value

toEncoding :: GetShardIterator -> Encoding

toJSONList :: [GetShardIterator] -> Value

toEncodingList :: [GetShardIterator] -> Encoding

NFData GetShardIterator

Methods

rnf :: GetShardIterator -> ()

AWSRequest GetShardIterator

Associated Types

type Rs GetShardIterator :: *

Methods

request :: GetShardIterator -> Request GetShardIterator

response :: MonadResource m => Logger -> Service -> Proxy * GetShardIterator -> ClientResponse -> m (Response GetShardIterator)

ToQuery GetShardIterator

Methods

toQuery :: GetShardIterator -> QueryString

ToPath GetShardIterator

Methods

toPath :: GetShardIterator -> ByteString

ToHeaders GetShardIterator

Methods

toHeaders :: GetShardIterator -> [Header]

type Rep GetShardIterator

type Rep GetShardIterator = D1 (MetaData "GetShardIterator" "Network.AWS.Kinesis.GetShardIterator" "amazonka-kinesis-1.4.3-Ae0nwQ55647lNwGKtUEHQ" False) (C1 (MetaCons "GetShardIterator'" PrefixI True) ((:*:) ((:*:) (S1 (MetaSel (Just Symbol "_gsiStartingSequenceNumber") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Maybe Text))) (S1 (MetaSel (Just Symbol "_gsiTimestamp") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Maybe POSIX)))) ((:*:) (S1 (MetaSel (Just Symbol "_gsiStreamName") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 Text)) ((:*:) (S1 (MetaSel (Just Symbol "_gsiShardId") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 Text)) (S1 (MetaSel (Just Symbol "_gsiShardIteratorType") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 ShardIteratorType))))))

type Rs GetShardIterator

type Rs GetShardIterator = GetShardIteratorResponse

Request Lenses

gsiStartingSequenceNumber :: Lens' GetShardIterator (Maybe Text)

The sequence number of the data record in the shard from which to start reading. Used with shard iterator type AT_SEQUENCE_NUMBER and AFTER_SEQUENCE_NUMBER.

gsiTimestamp :: Lens' GetShardIterator (Maybe UTCTime)

The timestamp of the data record from which to start reading. Used with shard iterator type AT_TIMESTAMP. A timestamp is the Unix epoch date with precision in milliseconds. For example, '2016-04-04T19:58:46.480-00:00' or '1459799926.480'. If a record with this exact timestamp does not exist, the iterator returned is for the next (later) record. If the timestamp is older than the current trim horizon, the iterator returned is for the oldest untrimmed data record (TRIM_HORIZON).

gsiStreamName :: Lens' GetShardIterator Text

The name of the Amazon Kinesis stream.

gsiShardId :: Lens' GetShardIterator Text

The shard ID of the Amazon Kinesis shard to get the iterator for.

gsiShardIteratorType :: Lens' GetShardIterator ShardIteratorType

Determines how the shard iterator is used to start reading data records from the shard.

The following are the valid Amazon Kinesis shard iterator types:

• AT_SEQUENCE_NUMBER - Start reading from the position denoted by a specific sequence number, provided in the value StartingSequenceNumber.
• AFTER_SEQUENCE_NUMBER - Start reading right after the position denoted by a specific sequence number, provided in the value StartingSequenceNumber.
• AT_TIMESTAMP - Start reading from the position denoted by a specific timestamp, provided in the value Timestamp.
• TRIM_HORIZON - Start reading at the last untrimmed record in the shard in the system, which is the oldest data record in the shard.
• LATEST - Start reading just after the most recent record in the shard, so that you always read the most recent data in the shard.

Destructuring the Response

getShardIteratorResponse

Arguments

:: Int

gsirsResponseStatus

-> GetShardIteratorResponse

Creates a value of GetShardIteratorResponse with the minimum fields required to make a request.

Use one of the following lenses to modify other fields as desired:

• gsirsShardIterator
• gsirsResponseStatus

data GetShardIteratorResponse

Represents the output for GetShardIterator.

See: getShardIteratorResponse smart constructor.

Instances

Eq GetShardIteratorResponse

Methods

(==) :: GetShardIteratorResponse -> GetShardIteratorResponse -> Bool

(/=) :: GetShardIteratorResponse -> GetShardIteratorResponse -> Bool

Data GetShardIteratorResponse

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> GetShardIteratorResponse -> c GetShardIteratorResponse

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c GetShardIteratorResponse

toConstr :: GetShardIteratorResponse -> Constr

dataTypeOf :: GetShardIteratorResponse -> DataType

dataCast1 :: Typeable (* -> *) t => (forall d. Data d => c (t d)) -> Maybe (c GetShardIteratorResponse)

dataCast2 :: Typeable (* -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c GetShardIteratorResponse)

gmapT :: (forall b. Data b => b -> b) -> GetShardIteratorResponse -> GetShardIteratorResponse

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> GetShardIteratorResponse -> r

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> GetShardIteratorResponse -> r

gmapQ :: (forall d. Data d => d -> u) -> GetShardIteratorResponse -> [u]

gmapQi :: Int -> (forall d. Data d => d -> u) -> GetShardIteratorResponse -> u

gmapM :: Monad m => (forall d. Data d => d -> m d) -> GetShardIteratorResponse -> m GetShardIteratorResponse

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> GetShardIteratorResponse -> m GetShardIteratorResponse

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> GetShardIteratorResponse -> m GetShardIteratorResponse

Read GetShardIteratorResponse

Methods

readsPrec :: Int -> ReadS GetShardIteratorResponse

readList :: ReadS [GetShardIteratorResponse]

readPrec :: ReadPrec GetShardIteratorResponse

readListPrec :: ReadPrec [GetShardIteratorResponse]

Show GetShardIteratorResponse

Methods

showsPrec :: Int -> GetShardIteratorResponse -> ShowS

show :: GetShardIteratorResponse -> String

showList :: [GetShardIteratorResponse] -> ShowS

Generic GetShardIteratorResponse

Associated Types

type Rep GetShardIteratorResponse :: * -> *

Methods

from :: GetShardIteratorResponse -> Rep GetShardIteratorResponse x

to :: Rep GetShardIteratorResponse x -> GetShardIteratorResponse

NFData GetShardIteratorResponse

Methods

rnf :: GetShardIteratorResponse -> ()

type Rep GetShardIteratorResponse

type Rep GetShardIteratorResponse = D1 (MetaData "GetShardIteratorResponse" "Network.AWS.Kinesis.GetShardIterator" "amazonka-kinesis-1.4.3-Ae0nwQ55647lNwGKtUEHQ" False) (C1 (MetaCons "GetShardIteratorResponse'" PrefixI True) ((:*:) (S1 (MetaSel (Just Symbol "_gsirsShardIterator") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 (Maybe Text))) (S1 (MetaSel (Just Symbol "_gsirsResponseStatus") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 Int))))

Response Lenses

gsirsShardIterator :: Lens' GetShardIteratorResponse (Maybe Text)

The position in the shard from which to start reading data records sequentially. A shard iterator specifies this position using the sequence number of a data record in a shard.

gsirsResponseStatus :: Lens' GetShardIteratorResponse Int

The response status code.