/* * Copyright 2010-2023 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://aws.amazon.com/apache2.0 * * 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. */ package com.amazonaws.retry; import com.amazonaws.AmazonClientException; import com.amazonaws.AmazonWebServiceRequest; import com.amazonaws.ClientConfiguration; import com.amazonaws.annotation.Immutable; import com.amazonaws.annotation.SdkInternalApi; import com.amazonaws.retry.internal.RetryModeResolver; /** * Retry policy that can be configured on a specific service client using * {@link ClientConfiguration}. This class is immutable, therefore safe to be * shared by multiple clients. * * @see ClientConfiguration * @see PredefinedRetryPolicies */ @Immutable public final class RetryPolicy { private static final RetryModeResolver RETRY_MODE_RESOLVER = new RetryModeResolver(); /** * Condition on whether a request should be retried. This field * should not be null. */ private final RetryCondition retryCondition; /** * Back-off strategy to control the sleep time between retry attempts. This * field should not be null. */ private final BackoffStrategy backoffStrategy; /** * Non-negative integer indicating the max retry count. */ private final int maxErrorRetry; /** * Whether this retry policy should honor the max error retry set in ClientConfiguration. * @see ClientConfiguration#setMaxErrorRetry(int) */ private final boolean honorMaxErrorRetryInClientConfig; /** * The retry mode to use */ private final RetryMode retryMode; /** * Whether it should honor the default max error retry in {@link RetryMode} */ private final boolean honorDefaultMaxErrorRetryInRetryMode; /** * Whether to fail fast when rate limiting is enabled and not enough * capacity is available to execute the request immediately. */ private final boolean fastFailRateLimiting; /** * Whether it should honor the default backoff strategy in {@link RetryMode} */ private final boolean honorBackoffStrategyInRetryMode; /** * Constructs a new retry policy. See {@link PredefinedRetryPolicies} for * some pre-defined policy components, and also the default policies used by * SDK. * * @param retryCondition * Retry condition on whether a specific request and exception * should be retried. If null value is specified, the SDK' * default retry condition is used. * @param backoffStrategy * Back-off strategy for controlling how long the next retry * should wait. If null value is specified, the SDK' default * exponential back-off strategy is used. * @param maxErrorRetry * Maximum number of retry attempts for failed requests. * @param honorMaxErrorRetryInClientConfig * Whether this retry policy should honor the max error retry set * by {@link ClientConfiguration#setMaxErrorRetry(int)} * @see ClientConfiguration * @see PredefinedRetryPolicies */ public RetryPolicy(RetryCondition retryCondition, BackoffStrategy backoffStrategy, int maxErrorRetry, boolean honorMaxErrorRetryInClientConfig) { this(retryCondition, backoffStrategy, maxErrorRetry, honorMaxErrorRetryInClientConfig, false, false); } @SdkInternalApi public RetryPolicy(RetryCondition retryCondition, BackoffStrategy backoffStrategy, int maxErrorRetry, boolean honorMaxErrorRetryInClientConfig, boolean honorDefaultMaxErrorRetryInRetryMode, boolean honorBackoffStrategyInRetryMode) { this(retryCondition, backoffStrategy, maxErrorRetry, honorMaxErrorRetryInClientConfig, null, honorDefaultMaxErrorRetryInRetryMode, false, honorBackoffStrategyInRetryMode); } public RetryPolicy(RetryCondition retryCondition, BackoffStrategy backoffStrategy, int maxErrorRetry, boolean honorMaxErrorRetryInClientConfig, RetryMode retryMode) { this(retryCondition, backoffStrategy, maxErrorRetry, honorMaxErrorRetryInClientConfig, retryMode, false, false, false); } private RetryPolicy(RetryPolicyBuilder builder) { this(builder.retryCondition, builder.backoffStrategy, builder.maxErrorRetry, builder.honorMaxErrorRetryInClientConfig, builder.retryMode, builder.honorDefaultMaxErrorRetryInRetryMode, builder.fastFailRateLimiting, builder.honorBackOffStrategyInRetryMode); } @SdkInternalApi RetryPolicy(RetryCondition retryCondition, BackoffStrategy backoffStrategy, int maxErrorRetry, boolean honorMaxErrorRetryInClientConfig, RetryMode retryMode, boolean honorDefaultMaxErrorRetryInRetryMode, boolean fastFailRateLimiting, boolean honorBackoffStrategyInRetryMode) { if (retryCondition == null) { retryCondition = PredefinedRetryPolicies.DEFAULT_RETRY_CONDITION; } if (maxErrorRetry < 0) { throw new IllegalArgumentException("Please provide a non-negative value for maxErrorRetry."); } if (backoffStrategy == null) { backoffStrategy = PredefinedRetryPolicies.DEFAULT_BACKOFF_STRATEGY; } this.honorDefaultMaxErrorRetryInRetryMode = honorDefaultMaxErrorRetryInRetryMode; this.retryCondition = retryCondition; this.maxErrorRetry = maxErrorRetry; this.honorMaxErrorRetryInClientConfig = honorMaxErrorRetryInClientConfig; this.retryMode = retryMode != null ? retryMode : RETRY_MODE_RESOLVER.retryMode(); this.honorBackoffStrategyInRetryMode = honorBackoffStrategyInRetryMode; if (honorBackoffStrategyInRetryMode) { this.backoffStrategy = PredefinedRetryPolicies.getDefaultBackoffStrategy(this.retryMode); } else { this.backoffStrategy = backoffStrategy; } this.fastFailRateLimiting = fastFailRateLimiting; } /** * Returns the retry condition included in this retry policy. * * @return The retry condition included in this retry policy. */ public RetryCondition getRetryCondition() { return retryCondition; } /** * Returns the back-off strategy included in this retry policy. * * @return The back-off strategy included in this retry policy. */ public BackoffStrategy getBackoffStrategy() { return backoffStrategy; } /** * Returns the maximum number of retry attempts. * * @return The maximum number of retry attempts. */ public int getMaxErrorRetry() { return maxErrorRetry; } /** * Returns whether this retry policy should honor the max error retry set in * ClientConfiguration. * * @return Whether this retry policy should honor the max error retry set in * ClientConfiguration * @see ClientConfiguration#setMaxErrorRetry(int) */ public boolean isMaxErrorRetryInClientConfigHonored() { return honorMaxErrorRetryInClientConfig; } /** * Returns the {@link RetryMode} to be used. * * @return retryMode */ public RetryMode getRetryMode() { return retryMode; } /** * Whether the client should fail immediately when {@link RetryMode#ADAPTIVE} is enabled, and there is not enough * capacity in the rate limiter to execute the request immediately. *

* The default configuration value is {@code false}, which will cause client to wait until enough capacity is * available. * * @return The fast fail configuration value. */ public boolean isFastFailRateLimiting() { return fastFailRateLimiting; } /** * @return Whether the default max error in retry mode should be honored. */ boolean isDefaultMaxErrorRetryInRetryModeHonored() { return honorDefaultMaxErrorRetryInRetryMode; } /** * @return Whether the default backoff strategy in retry mode should be honored. */ boolean isBackoffStrategyInRetryModeHonored() { return honorBackoffStrategyInRetryMode; } /** * @return A builder for conveniently building a retry policy. */ public static RetryPolicyBuilder builder() { return new RetryPolicyBuilder(); } public static final class RetryPolicyBuilder { private RetryCondition retryCondition; private BackoffStrategy backoffStrategy; private int maxErrorRetry; private boolean honorMaxErrorRetryInClientConfig; private RetryMode retryMode; private boolean honorDefaultMaxErrorRetryInRetryMode; private boolean fastFailRateLimiting; private boolean honorBackOffStrategyInRetryMode; /** * Set the retry condition on whether a specific request and exception should be retried. If null value is * specified, the SDK' *default retry condition is used. * * @param retryCondition The retry condition. * @return This object for method chaining. */ public RetryPolicyBuilder withRetryCondition(RetryCondition retryCondition) { this.retryCondition = retryCondition; return this; } public void setRetryCondition(RetryCondition retryCondition) { withRetryCondition(retryCondition); } /** * Set the back-off strategy for controlling how long the next retry should wait. If null value is specified, * the SDK' default exponential back-off strategy is used. * * @param backoffStrategy The backoff strategy. * @return This object for method chaining. */ public RetryPolicyBuilder withBackoffStrategy(BackoffStrategy backoffStrategy) { this.backoffStrategy = backoffStrategy; return this; } public void setBackoffStrategy(BackoffStrategy backoffStrategy) { withBackoffStrategy(backoffStrategy); } /** * Set aximum number of retry attempts for failed requests. * * @param maxErrorRetry The max retry attempts. * @return This object for method chaining. */ public RetryPolicyBuilder withMaxErrorRetry(int maxErrorRetry) { this.maxErrorRetry = maxErrorRetry; return this; } public void setMaxErrorRetry(int maxErrorRetry) { withMaxErrorRetry(maxErrorRetry); } /** * Set whether this retry policy should honor the max error retry set by {@link * ClientConfiguration#setMaxErrorRetry(int)}. * * @param honorMaxErrorRetryInClientConfig Whether the policy should honor the max error retry setting on the * client configuration. * * @return This object for method chaining. */ public RetryPolicyBuilder withHonorMaxErrorRetryInClientConfig(boolean honorMaxErrorRetryInClientConfig) { this.honorMaxErrorRetryInClientConfig = honorMaxErrorRetryInClientConfig; return this; } public void setHonorMaxErrorRetryInClientConfig(boolean honorMaxErrorRetryInClientConfig) { withHonorMaxErrorRetryInClientConfig(honorMaxErrorRetryInClientConfig); } /** * Set the retry mode for the client. * * @param retryMode The retry mode. * * @return This object for method chaining. */ public RetryPolicyBuilder withRetryMode(RetryMode retryMode) { this.retryMode = retryMode; return this; } public void setRetryMode(RetryMode retryMode) { withRetryMode(retryMode); } /** * Whether the policy should honor the max error retries dictated by the configured retry mode. * * @param honorDefaultMaxErrorRetryInRetryMode Whether the policy should honor the max error retries dictated * by the configured retry mode. * @return This object for method chaining. */ public RetryPolicyBuilder withHonorDefaultMaxErrorRetryInRetryMode(boolean honorDefaultMaxErrorRetryInRetryMode) { this.honorDefaultMaxErrorRetryInRetryMode = honorDefaultMaxErrorRetryInRetryMode; return this; } public void setHonorDefaultMaxErrorRetryInRetryMode(boolean honorDefaultMaxErrorRetryInRetryMode) { withHonorDefaultMaxErrorRetryInRetryMode(honorDefaultMaxErrorRetryInRetryMode); } /** * Whether the client should fail immediately when it cannot immediately make a request because there is not enough capacity in the rate limiter. *

* Note: This configuration only has an effect when used in combination with the {@link RetryMode#ADAPTIVE} retry mode. * * @param fastFailRateLimiting Whether to fail fast. * * @return This object for method chaining. */ public RetryPolicyBuilder withFastFailRateLimiting(boolean fastFailRateLimiting) { this.fastFailRateLimiting = fastFailRateLimiting; return this; } public void setFastFailRateLimiting(boolean fastFailRateLimiting) { withFastFailRateLimiting(fastFailRateLimiting); } /** * Whether the policy should honor the backoff strategy dictated by the configured retry mode. * * @param honorBackOffStrategyInRetryMode Whether the policy should honor the backoff strategy dictated * by the configured retry mode. * @return This object for method chaining. */ public RetryPolicyBuilder withHonorDefaultBackoffStrategyInRetryMode(boolean honorBackOffStrategyInRetryMode) { this.honorBackOffStrategyInRetryMode = honorBackOffStrategyInRetryMode; return this; } public void setHonorDefaultBackoffStrategyInRetryMode(boolean honorBackOffStrategyInRetryMode) { withHonorDefaultBackoffStrategyInRetryMode(honorBackOffStrategyInRetryMode); } public RetryPolicy build() { return new RetryPolicy(this); } } /** * The hook for providing custom condition on whether a failed request * should be retried. */ public interface RetryCondition { RetryCondition NO_RETRY_CONDITION = new RetryCondition() { @Override public boolean shouldRetry(AmazonWebServiceRequest originalRequest, AmazonClientException exception, int retriesAttempted) { return false; } }; /** * Returns whether a failed request should be retried according to the * given request context. In the following circumstances, the request * will fail directly without consulting this method: *

* * @param originalRequest * The original request object being executed. For * performance reason, this object is not a defensive copy, * and caller should not attempt to modify its data. * @param exception * The exception from the failed request, represented as an * AmazonClientException object. There are two types of * exception that will be passed to this method: * * Any other exceptions are regarded as unexpected failures * and are thrown immediately without any retry. For * performance reason, this object is not a defensive copy, * and caller should not attempt to modify its data. * @param retriesAttempted * The number of times the current request has been * attempted. * * @return True if the failed request should be retried. */ boolean shouldRetry(AmazonWebServiceRequest originalRequest, AmazonClientException exception, int retriesAttempted); } /** * The hook for providing custom back-off strategy to control the sleep time * between retries. */ public interface BackoffStrategy { RetryPolicy.BackoffStrategy NO_DELAY = new BackoffStrategy() { @Override public long delayBeforeNextRetry(AmazonWebServiceRequest originalRequest, AmazonClientException exception, int retriesAttempted) { return 0; } }; /** * Returns the delay (in milliseconds) before next retry attempt. * * @param originalRequest * The original request object being executed. For * performance reason, this object is not a defensive copy, * and caller should not attempt to modify its data. * @param exception * The exception from the failed request, represented as an * AmazonClientException object. There are two types of * exception that will be passed to this method: * * Any other exceptions are regarded as unexpected failures * and are thrown immediately without any retry. For * performance reason, this object is not a defensive copy, * and caller should not attempt to modify its data. * @param retriesAttempted * The number of times the current request has been attempted * (not including the next attempt after the delay). * * @return The delay (in milliseconds) before next retry attempt. */ long delayBeforeNextRetry(AmazonWebServiceRequest originalRequest, AmazonClientException exception, int retriesAttempted); } }