Repository: james-project Updated Branches: refs/heads/master 4cdfef08a -> 1f390f4f3
MAILBOX-372 generating wait delay in WaitDelayGenerator Project: http://git-wip-us.apache.org/repos/asf/james-project/repo Commit: http://git-wip-us.apache.org/repos/asf/james-project/commit/bd656cf8 Tree: http://git-wip-us.apache.org/repos/asf/james-project/tree/bd656cf8 Diff: http://git-wip-us.apache.org/repos/asf/james-project/diff/bd656cf8 Branch: refs/heads/master Commit: bd656cf888086b4bfb6caae401746287f2e8eedc Parents: 2c60acb Author: tran tien duc <dt...@linagora.com> Authored: Tue Jan 15 14:56:03 2019 +0700 Committer: tran tien duc <dt...@linagora.com> Committed: Wed Jan 16 14:07:50 2019 +0700 ---------------------------------------------------------------------- .../mailbox/events/WaitDelayGenerator.java | 71 ++++++++++++++++++++ .../mailbox/events/WaitDelayGeneratorTest.java | 58 ++++++++++++++++ 2 files changed, 129 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/james-project/blob/bd656cf8/mailbox/event/event-rabbitmq/src/main/java/org/apache/james/mailbox/events/WaitDelayGenerator.java ---------------------------------------------------------------------- diff --git a/mailbox/event/event-rabbitmq/src/main/java/org/apache/james/mailbox/events/WaitDelayGenerator.java b/mailbox/event/event-rabbitmq/src/main/java/org/apache/james/mailbox/events/WaitDelayGenerator.java new file mode 100644 index 0000000..fdcf9cc --- /dev/null +++ b/mailbox/event/event-rabbitmq/src/main/java/org/apache/james/mailbox/events/WaitDelayGenerator.java @@ -0,0 +1,71 @@ +/**************************************************************** + * Licensed to the Apache Software Foundation (ASF) under one * + * or more contributor license agreements. See the NOTICE file * + * distributed with this work for additional information * + * regarding copyright ownership. The ASF licenses this file * + * to you under the Apache License, Version 2.0 (the * + * "License"); you may not use this file except in compliance * + * with the License. You may obtain a copy of the License at * + * * + * http://www.apache.org/licenses/LICENSE-2.0 * + * * + * Unless required by applicable law or agreed to in writing, * + * software distributed under the License 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 org.apache.james.mailbox.events; + +import java.security.SecureRandom; +import java.time.Duration; + +import com.google.common.annotations.VisibleForTesting; +import com.google.common.base.Preconditions; + +import reactor.core.publisher.Mono; + +class WaitDelayGenerator { + + static WaitDelayGenerator of(RetryBackoff retryBackoff) { + return new WaitDelayGenerator(retryBackoff); + } + + private static int randomBetween(int lowest, int highest) { + Preconditions.checkArgument(lowest <= highest, "lowest always has to be less than or equals highest"); + return SECURE_RANDOM.nextInt(highest - lowest) + lowest; + } + + private static final SecureRandom SECURE_RANDOM = new SecureRandom(); + + private final RetryBackoff retryBackoff; + + private WaitDelayGenerator(RetryBackoff retryBackoff) { + this.retryBackoff = retryBackoff; + } + + Mono<Integer> delayIfHaveTo(int retryCount) { + Mono<Integer> countRetryMono = Mono.just(retryCount); + if (retryCount < 1) { + return countRetryMono; + } + + return countRetryMono + .filter(count -> count <= retryBackoff.getMaxRetries()) + .delayElement(generateDelay(retryCount)); + } + + @VisibleForTesting + Duration generateDelay(int retryCount) { + if (retryCount < 1) { + return Duration.ZERO; + } + int exponentialFactor = Double.valueOf(Math.pow(2, retryCount - 1)).intValue(); + int minDelay = exponentialFactor * (int) retryBackoff.getFirstBackoff().toMillis(); + int maxDelay = Double.valueOf(minDelay + minDelay * retryBackoff.getJitterFactor()).intValue(); + + return Duration.ofMillis(randomBetween(minDelay, maxDelay)); + } +} http://git-wip-us.apache.org/repos/asf/james-project/blob/bd656cf8/mailbox/event/event-rabbitmq/src/test/java/org/apache/james/mailbox/events/WaitDelayGeneratorTest.java ---------------------------------------------------------------------- diff --git a/mailbox/event/event-rabbitmq/src/test/java/org/apache/james/mailbox/events/WaitDelayGeneratorTest.java b/mailbox/event/event-rabbitmq/src/test/java/org/apache/james/mailbox/events/WaitDelayGeneratorTest.java new file mode 100644 index 0000000..acc3a9f --- /dev/null +++ b/mailbox/event/event-rabbitmq/src/test/java/org/apache/james/mailbox/events/WaitDelayGeneratorTest.java @@ -0,0 +1,58 @@ +/**************************************************************** + * Licensed to the Apache Software Foundation (ASF) under one * + * or more contributor license agreements. See the NOTICE file * + * distributed with this work for additional information * + * regarding copyright ownership. The ASF licenses this file * + * to you under the Apache License, Version 2.0 (the * + * "License"); you may not use this file except in compliance * + * with the License. You may obtain a copy of the License at * + * * + * http://www.apache.org/licenses/LICENSE-2.0 * + * * + * Unless required by applicable law or agreed to in writing, * + * software distributed under the License 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 org.apache.james.mailbox.events; + +import static org.assertj.core.api.Assertions.assertThat; + +import java.time.Duration; + +import org.assertj.core.api.SoftAssertions; +import org.junit.jupiter.api.Test; + +class WaitDelayGeneratorTest { + + @Test + void generateDelayShouldReturnZeroWhenZeroRetryCount() { + WaitDelayGenerator generator = WaitDelayGenerator.of(RetryBackoff.defaultRetryBackoff()); + + assertThat(generator.generateDelay(0)) + .isEqualTo(Duration.ofMillis(0)); + } + + @Test + void generateDelayShouldReturnByRandomInRangeOfExponentialGrowthOfRetryCount() { + WaitDelayGenerator generator = WaitDelayGenerator.of(RetryBackoff.builder() + .maxRetries(4) + .firstBackoff(Duration.ofMillis(100)) + .jitterFactor(0.5) + .build()); + + SoftAssertions.assertSoftly(softly -> { + softly.assertThat(generator.generateDelay(1).toMillis()) + .isBetween(100L, 150L); + softly.assertThat(generator.generateDelay(2).toMillis()) + .isBetween(200L, 300L); + softly.assertThat(generator.generateDelay(3).toMillis()) + .isBetween(400L, 600L); + softly.assertThat(generator.generateDelay(4).toMillis()) + .isBetween(800L, 1200L); + }); + } +} \ No newline at end of file --------------------------------------------------------------------- To unsubscribe, e-mail: server-dev-unsubscr...@james.apache.org For additional commands, e-mail: server-dev-h...@james.apache.org
