Java RetryPolicy.BackoffStrategy方法代码示例

import com.amazonaws.retry.RetryPolicy; //导入方法依赖的package包/类
@Provides
protected ApiGateway provideAmazonApiGateway(AWSCredentialsProvider credsProvider,
                                             RetryPolicy.BackoffStrategy backoffStrategy,
                                             @Named("region") String region) {

    final RetryPolicy retrypolicy = new RetryPolicy(PredefinedRetryPolicies.DEFAULT_RETRY_CONDITION, backoffStrategy, 5, true);

    final ClientConfiguration clientConfig = new ClientConfiguration().withUserAgent(USER_AGENT).withRetryPolicy(retrypolicy);

    return new AmazonApiGateway(getEndpoint(region)).with(credsProvider).with(clientConfig).getApiGateway();
}
 

import com.amazonaws.retry.RetryPolicy; //导入方法依赖的package包/类
@Provides
protected RetryPolicy.BackoffStrategy provideBackoffStrategy() {

    // tune these parameters to handle throttling errors
    final int maxBackoffInMilliseconds = 50 * 1000; // maximum exponential back-off time before retrying a request
    final int throttlingScaleFactor = 800; // base sleep time for throttling exceptions
    final int maxRetriesBeforeBackoff = 10; // log2(maxBackoffInMilliseconds/throttlingScaleFactor)

    final int baseScaleFactor = 600; // base sleep time for general exceptions
    final int throttlingScaleFactorRandomRange = throttlingScaleFactor / 4;

    final Random random = new Random();

    return (originalRequest, exception, retriesAttempted) -> {

        LOG.debug("Caught error from service. Retry attempt: " + retriesAttempted, exception);

        if (retriesAttempted < 0) return 0;
        if (retriesAttempted > maxRetriesBeforeBackoff) return maxBackoffInMilliseconds;

        int scaleFactor;
        if (exception instanceof AmazonServiceException
                && RetryUtils.isThrottlingException((AmazonServiceException) exception)) {
            scaleFactor = throttlingScaleFactor + random.nextInt(throttlingScaleFactorRandomRange);
        } else {
            scaleFactor = baseScaleFactor;
        }

        long delay = (1L << retriesAttempted) * scaleFactor;
        delay = Math.min(delay, maxBackoffInMilliseconds);

        LOG.info("Client backing off for " + delay + "ms");

        return delay;
    };
}
 

import com.amazonaws.retry.RetryPolicy; //导入方法依赖的package包/类
protected static ClientConfiguration buildConfiguration(Logger logger, Settings settings) {
    ClientConfiguration clientConfiguration = new ClientConfiguration();
    // the response metadata cache is only there for diagnostics purposes,
    // but can force objects from every response to the old generation.
    clientConfiguration.setResponseMetadataCacheSize(0);
    clientConfiguration.setProtocol(CLOUD_EC2.PROTOCOL_SETTING.get(settings));

    if (PROXY_HOST_SETTING.exists(settings) || CLOUD_EC2.PROXY_HOST_SETTING.exists(settings)) {
        String proxyHost = CLOUD_EC2.PROXY_HOST_SETTING.get(settings);
        Integer proxyPort = CLOUD_EC2.PROXY_PORT_SETTING.get(settings);
        String proxyUsername = CLOUD_EC2.PROXY_USERNAME_SETTING.get(settings);
        String proxyPassword = CLOUD_EC2.PROXY_PASSWORD_SETTING.get(settings);

        clientConfiguration
            .withProxyHost(proxyHost)
            .withProxyPort(proxyPort)
            .withProxyUsername(proxyUsername)
            .withProxyPassword(proxyPassword);
    }

    // #155: we might have 3rd party users using older EC2 API version
    String awsSigner = CLOUD_EC2.SIGNER_SETTING.get(settings);
    if (Strings.hasText(awsSigner)) {
        logger.debug("using AWS API signer [{}]", awsSigner);
        AwsSigner.configureSigner(awsSigner, clientConfiguration);
    }

    // Increase the number of retries in case of 5xx API responses
    final Random rand = Randomness.get();
    RetryPolicy retryPolicy = new RetryPolicy(
        RetryPolicy.RetryCondition.NO_RETRY_CONDITION,
        new RetryPolicy.BackoffStrategy() {
            @Override
            public long delayBeforeNextRetry(AmazonWebServiceRequest originalRequest,
                                             AmazonClientException exception,
                                             int retriesAttempted) {
                // with 10 retries the max delay time is 320s/320000ms (10 * 2^5 * 1 * 1000)
                logger.warn("EC2 API request failed, retry again. Reason was:", exception);
                return 1000L * (long) (10d * Math.pow(2, retriesAttempted / 2.0d) * (1.0d + rand.nextDouble()));
            }
        },
        10,
        false);
    clientConfiguration.setRetryPolicy(retryPolicy);
    clientConfiguration.setSocketTimeout((int) CLOUD_EC2.READ_TIMEOUT.get(settings).millis());

    return clientConfiguration;
}
 

import com.amazonaws.retry.RetryPolicy; //导入方法依赖的package包/类
@Bean
RetryPolicy.BackoffStrategy instrumentedBackoffStrategy(Registry registry) {
  return new InstrumentedBackoffStrategy(registry);
}
 

import com.amazonaws.retry.RetryPolicy; //导入方法依赖的package包/类
public InstrumentedBackoffStrategy(Registry registry, RetryPolicy.BackoffStrategy delegate) {
  this.registry = Objects.requireNonNull(registry, "registry");
  this.delegate = Objects.requireNonNull(delegate, "delegate");
}