Verwenden Sie GetRecords mit einem AWS SDK oder CLI

Um Datensätze von einem Shard abzurufen

Im folgenden get-records Beispiel werden Datensätze aus dem Shard eines Kinesis-Datenstreams mithilfe des angegebenen Shard-Iterators abgerufen.

aws kinesis get-records \
    --shard-iterator AAAAAAAAAAF7/0mWD7IuHj1yGv/TKuNgx2ukD5xipCY4cy4gU96orWwZwcSXh3K9tAmGYeOZyLZrvzzeOFVf9iN99hUPw/w/b0YWYeehfNvnf1DYt5XpDJghLKr3DzgznkTmMymDP3R+3wRKeuEw6/kdxY2yKJH0veaiekaVc4N2VwK/GvaGP2Hh9Fg7N++q0Adg6fIDQPt4p8RpavDbk+A4sL9SWGE1

Ausgabe:

{
    "Records": [],
    "MillisBehindLatest": 80742000
}

Weitere Informationen finden Sie unter Developing Consumers Using the Kinesis Data Streams API with the AWS SDK for Java im Amazon Kinesis Data Streams Developer Guide.

import software.amazon.awssdk.core.SdkBytes;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.kinesis.KinesisClient;
import software.amazon.awssdk.services.kinesis.model.DescribeStreamResponse;
import software.amazon.awssdk.services.kinesis.model.DescribeStreamRequest;
import software.amazon.awssdk.services.kinesis.model.Shard;
import software.amazon.awssdk.services.kinesis.model.GetShardIteratorRequest;
import software.amazon.awssdk.services.kinesis.model.GetShardIteratorResponse;
import software.amazon.awssdk.services.kinesis.model.Record;
import software.amazon.awssdk.services.kinesis.model.GetRecordsRequest;
import software.amazon.awssdk.services.kinesis.model.GetRecordsResponse;
import java.util.ArrayList;
import java.util.List;

/**
 * Before running this Java V2 code example, set up your development
 * environment, including your credentials.
 *
 * For more information, see the following documentation topic:
 *
 * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html
 */
public class GetRecords {
    public static void main(String[] args) {
        final String usage = """

                Usage:
                    <streamName>

                Where:
                    streamName - The Amazon Kinesis data stream to read from (for example, StockTradeStream).
                """;

        if (args.length != 1) {
            System.out.println(usage);
            System.exit(1);
        }

        String streamName = args[0];
        Region region = Region.US_EAST_1;
        KinesisClient kinesisClient = KinesisClient.builder()
                .region(region)
                .build();

        getStockTrades(kinesisClient, streamName);
        kinesisClient.close();
    }

    public static void getStockTrades(KinesisClient kinesisClient, String streamName) {
        String shardIterator;
        String lastShardId = null;
        DescribeStreamRequest describeStreamRequest = DescribeStreamRequest.builder()
                .streamName(streamName)
                .build();

        List<Shard> shards = new ArrayList<>();
        DescribeStreamResponse streamRes;
        do {
            streamRes = kinesisClient.describeStream(describeStreamRequest);
            shards.addAll(streamRes.streamDescription().shards());

            if (shards.size() > 0) {
                lastShardId = shards.get(shards.size() - 1).shardId();
            }
        } while (streamRes.streamDescription().hasMoreShards());

        GetShardIteratorRequest itReq = GetShardIteratorRequest.builder()
                .streamName(streamName)
                .shardIteratorType("TRIM_HORIZON")
                .shardId(lastShardId)
                .build();

        GetShardIteratorResponse shardIteratorResult = kinesisClient.getShardIterator(itReq);
        shardIterator = shardIteratorResult.shardIterator();

        // Continuously read data records from shard.
        List<Record> records;

        // Create new GetRecordsRequest with existing shardIterator.
        // Set maximum records to return to 1000.
        GetRecordsRequest recordsRequest = GetRecordsRequest.builder()
                .shardIterator(shardIterator)
                .limit(1000)
                .build();

        GetRecordsResponse result = kinesisClient.getRecords(recordsRequest);

        // Put result into record list. Result may be empty.
        records = result.records();

        // Print records
        for (Record record : records) {
            SdkBytes byteBuffer = record.data();
            System.out.printf("Seq No: %s - %s%n", record.sequenceNumber(), new String(byteBuffer.asByteArray()));
        }
    }
}

Beispiel 1: Dieses Beispiel zeigt, wie Daten aus einer Reihe von einem oder mehreren Datensätzen zurückgegeben und extrahiert werden. Der an Get- gelieferte Iterator KINRecord bestimmt die Startposition der zurückzugebenden Datensätze, die in diesem Beispiel in einer Variablen, $records, erfasst werden. Auf jeden einzelnen Datensatz kann dann zugegriffen werden, indem die $records-Auflistung indexiert wird. Unter der Annahme, dass es sich bei den Daten im Datensatz um UTF -8-codierten Text handelt, zeigt der letzte Befehl, wie Sie die Daten aus dem MemoryStream Objekt extrahieren und als Text an die Konsole zurückgeben können.

$records
$records = Get-KINRecord -ShardIterator "AAAAAAAAAAGIc....9VnbiRNaP"

Ausgabe:

MillisBehindLatest NextShardIterator            Records
------------------ -----------------            -------
0                  AAAAAAAAAAERNIq...uDn11HuUs  {Key1, Key2}

$records.Records[0]

Ausgabe:

ApproximateArrivalTimestamp Data                   PartitionKey SequenceNumber
--------------------------- ----                   ------------ --------------
3/7/2016 5:14:33 PM         System.IO.MemoryStream Key1         4955986459776...931586

[Text.Encoding]::UTF8.GetString($records.Records[0].Data.ToArray())

Ausgabe:

test data from string

class KinesisStream:
    """Encapsulates a Kinesis stream."""

    def __init__(self, kinesis_client):
        """
        :param kinesis_client: A Boto3 Kinesis client.
        """
        self.kinesis_client = kinesis_client
        self.name = None
        self.details = None
        self.stream_exists_waiter = kinesis_client.get_waiter("stream_exists")


    def get_records(self, max_records):
        """
        Gets records from the stream. This function is a generator that first gets
        a shard iterator for the stream, then uses the shard iterator to get records
        in batches from the stream. Each batch of records is yielded back to the
        caller until the specified maximum number of records has been retrieved.

        :param max_records: The maximum number of records to retrieve.
        :return: Yields the current batch of retrieved records.
        """
        try:
            response = self.kinesis_client.get_shard_iterator(
                StreamName=self.name,
                ShardId=self.details["Shards"][0]["ShardId"],
                ShardIteratorType="LATEST",
            )
            shard_iter = response["ShardIterator"]
            record_count = 0
            while record_count < max_records:
                response = self.kinesis_client.get_records(
                    ShardIterator=shard_iter, Limit=10
                )
                shard_iter = response["NextShardIterator"]
                records = response["Records"]
                logger.info("Got %s records.", len(records))
                record_count += len(records)
                yield records
        except ClientError:
            logger.exception("Couldn't get records from stream %s.", self.name)
            raise

    TRY.
        oo_result = lo_kns->getrecords(             " oo_result is returned for testing purposes. "
            iv_sharditerator = iv_shard_iterator
        ).
        DATA(lt_records) = oo_result->get_records( ).
        MESSAGE 'Record retrieved.' TYPE 'I'.
      CATCH /aws1/cx_knsexpirediteratorex .
        MESSAGE 'Iterator expired.' TYPE 'E'.
      CATCH /aws1/cx_knsinvalidargumentex .
        MESSAGE 'The specified argument was not valid.' TYPE 'E'.
      CATCH /aws1/cx_knskmsaccessdeniedex .
        MESSAGE 'You do not have permission to perform this AWS KMS action.' TYPE 'E'.
      CATCH /aws1/cx_knskmsdisabledex .
        MESSAGE 'KMS key used is disabled.' TYPE 'E'.
      CATCH /aws1/cx_knskmsinvalidstateex .
        MESSAGE 'KMS key used is in an invalid state. ' TYPE 'E'.
      CATCH /aws1/cx_knskmsnotfoundex .
        MESSAGE 'KMS key used is not found.' TYPE 'E'.
      CATCH /aws1/cx_knskmsoptinrequired .
        MESSAGE 'KMS key option is required.' TYPE 'E'.
      CATCH /aws1/cx_knskmsthrottlingex .
        MESSAGE 'The rate of requests to AWS KMS is exceeding the request quotas.' TYPE 'E'.
      CATCH /aws1/cx_knsprovthruputexcdex .
        MESSAGE 'The request rate for the stream is too high, or the requested data is too large for the available throughput.' TYPE 'E'.
      CATCH /aws1/cx_knsresourcenotfoundex .
        MESSAGE 'Resource being accessed is not found.' TYPE 'E'.
    ENDTRY.