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我在本地运行具有两个不同端口的相同应用程序。我提供的代码仅用于测试。这里 access_key 和 secret_key 将在后期从环境变量中提供。

当我在不同的端口上运行相同的应用程序时，我看到两者都能够获取 dynamodb 分区键中的锁。

这对我来说是全新的。如果我需要从 AWS 控制台在 AWS DynamoDB 中创建任何锁定机制，请需要您的支持。

下面是 AWS 控制台 DynamoDB 表快照和代码片段，我可以在其中看到日志：“获得锁！如果我死了，我的锁将在 10 秒后过期。” 来自两个正在运行的实例。根据我的要求，如果我从一个实例锁定，则另一个实例不应该获取锁，它应该提供日志“获取锁失败！”。

在 Spring Boot 中执行代码时也出现错误。AmazonDynamoDBLockClient：心跳线程收到中断，正在退出 run()（可能正在退出线程）

在此处输入图像描述

@Component
public class AwsDynamoDBConfiguration {

    Logger logger = LoggerFactory.getLogger(AwsDynamoDBConfiguration.class);

    /**
     * AWS configuration.
     */
    @Autowired
    private AwsConfiguration awsConfiguration;

    private static final AwsClientBuilder.EndpointConfiguration DYNAMODB_ENDPOINT = new AwsClientBuilder.EndpointConfiguration(
        "https://dynamodb.us-east-1.amazonaws.com", "us-east-1");

    private Optional<LockItem> lockItem;
    private AmazonDynamoDBLockClient client;

    public boolean lockDynamoDB() throws InterruptedException, IOException {
    logger.info("Start : AWS DynamoDB lockDynamoDB");

    boolean isDynamoDBLockAccessed = false;

    final AmazonDynamoDB dynamoDB = AmazonDynamoDBClientBuilder.standard()
        .withEndpointConfiguration(DYNAMODB_ENDPOINT)
        .withCredentials(new AWSStaticCredentialsProvider(
            new BasicAWSCredentials("access_key", "secret_key")))
        .build();

    logger.info("DynamoDB created.");
    // Whether or not to create a heartbeating background thread
    final boolean createHeartbeatBackgroundThread = true;
    // build the lock client
    client = new AmazonDynamoDBLockClient(AmazonDynamoDBLockClientOptions.builder(dynamoDB, "tbl_test_lock")
        .withTimeUnit(TimeUnit.SECONDS).withLeaseDuration(100L).withHeartbeatPeriod(3L)
        .withCreateHeartbeatBackgroundThread(createHeartbeatBackgroundThread).build());
    logger.info("DynamoDB Client created.");
    // try to acquire a lock on the partition key "key"
    lockItem = client.tryAcquireLock(AcquireLockOptions.builder("key").build());
    logger.info("DynamoDB try acquire lock.");
    if (lockItem.isPresent()) {
        logger.info("Acquired lock! If I die, my lock will expire in 10 seconds.");
        logger.info("Otherwise, I will hold it until I stop heartbeating.");
        isDynamoDBLockAccessed = true;
    } else {
        logger.info("Failed to acquire lock!");
        isDynamoDBLockAccessed = false;
    }
    client.close();
    logger.info("End : AWS DynamoDB lockDynamoDB");
    return isDynamoDBLockAccessed;
    }

    @PreDestroy
    public void destroy() {
    logger.info("AWS DynamoDB Callback triggered - @PreDestroy.");
    if (client != null && lockItem != null && lockItem.isPresent()) {
        client.releaseLock(lockItem.get());
    }
    logger.info("AWS DynamoDB Lock has been released.");
    }
}
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1 回答 1

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需要在条件下获得锁定 (client.getLock("key", Optional.empty())) 并且它对我有用。

if (lockItem.isPresent()) {
            client.getLock("key", Optional.empty());
            logger.info("Acquired lock! If I die, my lock will expire in " + leaseDuration + " seconds.");
            logger.info("Otherwise, I will hold it until I stop heartbeating.");
            isDynamoDBLockAccessed = true;
} else {
            logger.info("Failed to acquire lock!");
            isDynamoDBLockAccessed = false;
}
于 2021-02-08T10:57:29.487 回答