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在 Java 中使用 KCL 2.x 开发增强型扇出消费者
您可以使用版本 2.0 或更高版本的 Kinesis 客户端库 (KCL) 在 Amazon Kinesis Data Streams 中开发应用程序,以便使用增强的扇出功能从流中接收数据。以下代码显示 ProcessorFactory
和 RecordProcessor
在 Java 中的实施示例。
建议您使用 KinesisClientUtil
创建 KinesisAsyncClient
,并在 KinesisAsyncClient
中配置 maxConcurrency
。
重要
Amazon Kinesis 户端可能会看到延迟大幅增加,除非您将 KinesisAsyncClient
配置为具有足够高的 maxConcurrency
,以允许所有租期以及额外使用 KinesisAsyncClient
。
/* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Licensed under the Amazon Software License (the "License"). * You may not use this file except in compliance with the License. * A copy of the License is located at * * http://aws.amazon.com/asl/ * * or in the "license" file accompanying this file. This file is distributed * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. See the License for the specific language governing * permissions and limitations under the License. */ /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Licensed under the Apache License, Version 2.0 (the "License"). * You may not use this file except in compliance with the License. * A copy of the License is located at * * http://www.apache.org/licenses/LICENSE-2.0 * * or in the "license" file accompanying this file. This file is distributed * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. See the License for the specific language governing * permissions and limitations under the License. */ import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.UUID; import java.util.concurrent.ExecutionException; import java.util.concurrent.Executors; import java.util.concurrent.Future; import java.util.concurrent.ScheduledExecutorService; import java.util.concurrent.ScheduledFuture; import java.util.concurrent.TimeUnit; import java.util.concurrent.TimeoutException; import org.apache.commons.lang3.ObjectUtils; import org.apache.commons.lang3.RandomStringUtils; import org.apache.commons.lang3.RandomUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.slf4j.MDC; import software.amazon.awssdk.core.SdkBytes; import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.cloudwatch.CloudWatchAsyncClient; import software.amazon.awssdk.services.dynamodb.DynamoDbAsyncClient; import software.amazon.awssdk.services.kinesis.KinesisAsyncClient; import software.amazon.awssdk.services.kinesis.model.PutRecordRequest; import software.amazon.kinesis.common.ConfigsBuilder; import software.amazon.kinesis.common.KinesisClientUtil; import software.amazon.kinesis.coordinator.Scheduler; import software.amazon.kinesis.exceptions.InvalidStateException; import software.amazon.kinesis.exceptions.ShutdownException; import software.amazon.kinesis.lifecycle.events.InitializationInput; import software.amazon.kinesis.lifecycle.events.LeaseLostInput; import software.amazon.kinesis.lifecycle.events.ProcessRecordsInput; import software.amazon.kinesis.lifecycle.events.ShardEndedInput; import software.amazon.kinesis.lifecycle.events.ShutdownRequestedInput; import software.amazon.kinesis.processor.ShardRecordProcessor; import software.amazon.kinesis.processor.ShardRecordProcessorFactory; public class SampleSingle { private static final Logger log = LoggerFactory.getLogger(SampleSingle.class); public static void main(String... args) { if (args.length < 1) { log.error("At a minimum, the stream name is required as the first argument. The Region may be specified as the second argument."); System.exit(1); } String streamName = args[0]; String region = null; if (args.length > 1) { region = args[1]; } new SampleSingle(streamName, region).run(); } private final String streamName; private final Region region; private final KinesisAsyncClient kinesisClient; private SampleSingle(String streamName, String region) { this.streamName = streamName; this.region = Region.of(ObjectUtils.firstNonNull(region, "us-east-2")); this.kinesisClient = KinesisClientUtil.createKinesisAsyncClient(KinesisAsyncClient.builder().region(this.region)); } private void run() { ScheduledExecutorService producerExecutor = Executors.newSingleThreadScheduledExecutor(); ScheduledFuture<?> producerFuture = producerExecutor.scheduleAtFixedRate(this::publishRecord, 10, 1, TimeUnit.SECONDS); DynamoDbAsyncClient dynamoClient = DynamoDbAsyncClient.builder().region(region).build(); CloudWatchAsyncClient cloudWatchClient = CloudWatchAsyncClient.builder().region(region).build(); ConfigsBuilder configsBuilder = new ConfigsBuilder(streamName, streamName, kinesisClient, dynamoClient, cloudWatchClient, UUID.randomUUID().toString(), new SampleRecordProcessorFactory()); Scheduler scheduler = new Scheduler( configsBuilder.checkpointConfig(), configsBuilder.coordinatorConfig(), configsBuilder.leaseManagementConfig(), configsBuilder.lifecycleConfig(), configsBuilder.metricsConfig(), configsBuilder.processorConfig(), configsBuilder.retrievalConfig() ); Thread schedulerThread = new Thread(scheduler); schedulerThread.setDaemon(true); schedulerThread.start(); System.out.println("Press enter to shutdown"); BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); try { reader.readLine(); } catch (IOException ioex) { log.error("Caught exception while waiting for confirm. Shutting down.", ioex); } log.info("Cancelling producer, and shutting down executor."); producerFuture.cancel(true); producerExecutor.shutdownNow(); Future<Boolean> gracefulShutdownFuture = scheduler.startGracefulShutdown(); log.info("Waiting up to 20 seconds for shutdown to complete."); try { gracefulShutdownFuture.get(20, TimeUnit.SECONDS); } catch (InterruptedException e) { log.info("Interrupted while waiting for graceful shutdown. Continuing."); } catch (ExecutionException e) { log.error("Exception while executing graceful shutdown.", e); } catch (TimeoutException e) { log.error("Timeout while waiting for shutdown. Scheduler may not have exited."); } log.info("Completed, shutting down now."); } private void publishRecord() { PutRecordRequest request = PutRecordRequest.builder() .partitionKey(RandomStringUtils.randomAlphabetic(5, 20)) .streamName(streamName) .data(SdkBytes.fromByteArray(RandomUtils.nextBytes(10))) .build(); try { kinesisClient.putRecord(request).get(); } catch (InterruptedException e) { log.info("Interrupted, assuming shutdown."); } catch (ExecutionException e) { log.error("Exception while sending data to Kinesis. Will try again next cycle.", e); } } private static class SampleRecordProcessorFactory implements ShardRecordProcessorFactory { public ShardRecordProcessor shardRecordProcessor() { return new SampleRecordProcessor(); } } private static class SampleRecordProcessor implements ShardRecordProcessor { private static final String SHARD_ID_MDC_KEY = "ShardId"; private static final Logger log = LoggerFactory.getLogger(SampleRecordProcessor.class); private String shardId; public void initialize(InitializationInput initializationInput) { shardId = initializationInput.shardId(); MDC.put(SHARD_ID_MDC_KEY, shardId); try { log.info("Initializing @ Sequence: {}", initializationInput.extendedSequenceNumber()); } finally { MDC.remove(SHARD_ID_MDC_KEY); } } public void processRecords(ProcessRecordsInput processRecordsInput) { MDC.put(SHARD_ID_MDC_KEY, shardId); try { log.info("Processing {} record(s)", processRecordsInput.records().size()); processRecordsInput.records().forEach(r -> log.info("Processing record pk: {} -- Seq: {}", r.partitionKey(), r.sequenceNumber())); } catch (Throwable t) { log.error("Caught throwable while processing records. Aborting."); Runtime.getRuntime().halt(1); } finally { MDC.remove(SHARD_ID_MDC_KEY); } } public void leaseLost(LeaseLostInput leaseLostInput) { MDC.put(SHARD_ID_MDC_KEY, shardId); try { log.info("Lost lease, so terminating."); } finally { MDC.remove(SHARD_ID_MDC_KEY); } } public void shardEnded(ShardEndedInput shardEndedInput) { MDC.put(SHARD_ID_MDC_KEY, shardId); try { log.info("Reached shard end checkpointing."); shardEndedInput.checkpointer().checkpoint(); } catch (ShutdownException | InvalidStateException e) { log.error("Exception while checkpointing at shard end. Giving up.", e); } finally { MDC.remove(SHARD_ID_MDC_KEY); } } public void shutdownRequested(ShutdownRequestedInput shutdownRequestedInput) { MDC.put(SHARD_ID_MDC_KEY, shardId); try { log.info("Scheduler is shutting down, checkpointing."); shutdownRequestedInput.checkpointer().checkpoint(); } catch (ShutdownException | InvalidStateException e) { log.error("Exception while checkpointing at requested shutdown. Giving up.", e); } finally { MDC.remove(SHARD_ID_MDC_KEY); } } } }