| /* |
| * 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.beam.sdk.util; |
| |
| import static org.hamcrest.Matchers.allOf; |
| import static org.hamcrest.Matchers.containsString; |
| import static org.hamcrest.Matchers.equalTo; |
| import static org.hamcrest.Matchers.greaterThanOrEqualTo; |
| import static org.hamcrest.Matchers.lessThan; |
| import static org.hamcrest.Matchers.lessThanOrEqualTo; |
| import static org.junit.Assert.assertEquals; |
| import static org.junit.Assert.assertThat; |
| |
| import java.io.IOException; |
| import org.joda.time.Duration; |
| import org.junit.Rule; |
| import org.junit.Test; |
| import org.junit.rules.ExpectedException; |
| import org.junit.runner.RunWith; |
| import org.junit.runners.JUnit4; |
| |
| /** Tests for {@link FluentBackoff}. */ |
| @RunWith(JUnit4.class) |
| public class FluentBackoffTest { |
| |
| @Rule public ExpectedException thrown = ExpectedException.none(); |
| private final FluentBackoff defaultBackoff = FluentBackoff.DEFAULT; |
| |
| @Test |
| public void testInvalidExponent() { |
| thrown.expect(IllegalArgumentException.class); |
| thrown.expectMessage("exponent -2.0 must be greater than 0"); |
| defaultBackoff.withExponent(-2.0); |
| } |
| |
| @Test |
| public void testInvalidInitialBackoff() { |
| thrown.expect(IllegalArgumentException.class); |
| thrown.expectMessage("initialBackoff PT0S must be at least 1 millisecond"); |
| defaultBackoff.withInitialBackoff(Duration.ZERO); |
| } |
| |
| @Test |
| public void testInvalidMaxBackoff() { |
| thrown.expect(IllegalArgumentException.class); |
| thrown.expectMessage("maxBackoff PT0S must be at least 1 millisecond"); |
| defaultBackoff.withMaxBackoff(Duration.ZERO); |
| } |
| |
| @Test |
| public void testInvalidMaxRetries() { |
| thrown.expect(IllegalArgumentException.class); |
| thrown.expectMessage("maxRetries -1 cannot be negative"); |
| defaultBackoff.withMaxRetries(-1); |
| } |
| |
| @Test |
| public void testInvalidCumulativeBackoff() { |
| thrown.expect(IllegalArgumentException.class); |
| thrown.expectMessage("maxCumulativeBackoff PT-0.002S must be at least 1 millisecond"); |
| defaultBackoff.withMaxCumulativeBackoff(Duration.millis(-2)); |
| } |
| |
| /** Tests with bounded interval, custom exponent, and unlimited retries. */ |
| @Test |
| public void testBoundedIntervalWithReset() throws Exception { |
| BackOff backOff = |
| FluentBackoff.DEFAULT |
| .withInitialBackoff(Duration.millis(500)) |
| .withMaxBackoff(Duration.standardSeconds(1)) |
| .backoff(); |
| assertThat(backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(249L), lessThan(751L))); |
| assertThat(backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(374L), lessThan(1126L))); |
| assertThat( |
| backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(500L), lessThanOrEqualTo(1500L))); |
| assertThat( |
| backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(500L), lessThanOrEqualTo(1500L))); |
| assertThat( |
| backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(500L), lessThanOrEqualTo(1500L))); |
| assertThat( |
| backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(500L), lessThanOrEqualTo(1500L))); |
| assertThat( |
| backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(500L), lessThanOrEqualTo(1500L))); |
| |
| // Reset, should go back to short times. |
| backOff.reset(); |
| assertThat(backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(249L), lessThan(751L))); |
| assertThat(backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(374L), lessThan(1126L))); |
| assertThat( |
| backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(500L), lessThanOrEqualTo(1500L))); |
| assertThat( |
| backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(500L), lessThanOrEqualTo(1500L))); |
| } |
| |
| /** Tests with bounded interval, custom exponent, limited retries, and a reset. */ |
| @Test |
| public void testMaxRetriesWithReset() throws Exception { |
| BackOff backOff = |
| FluentBackoff.DEFAULT.withInitialBackoff(Duration.millis(500)).withMaxRetries(1).backoff(); |
| assertThat(backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(249L), lessThan(751L))); |
| assertThat(backOff.nextBackOffMillis(), equalTo(BackOff.STOP)); |
| assertThat(backOff.nextBackOffMillis(), equalTo(BackOff.STOP)); |
| assertThat(backOff.nextBackOffMillis(), equalTo(BackOff.STOP)); |
| assertThat(backOff.nextBackOffMillis(), equalTo(BackOff.STOP)); |
| |
| backOff.reset(); |
| assertThat(backOff.nextBackOffMillis(), allOf(greaterThanOrEqualTo(249L), lessThan(751L))); |
| assertThat(backOff.nextBackOffMillis(), equalTo(BackOff.STOP)); |
| } |
| |
| private static long countMaximumBackoff(BackOff backOff) throws IOException { |
| long cumulativeBackoffMillis = 0; |
| long currentBackoffMillis = backOff.nextBackOffMillis(); |
| while (currentBackoffMillis != BackOff.STOP) { |
| cumulativeBackoffMillis += currentBackoffMillis; |
| currentBackoffMillis = backOff.nextBackOffMillis(); |
| } |
| return cumulativeBackoffMillis; |
| } |
| |
| /** Tests with bounded interval, custom exponent, limited cumulative time, and a reset. */ |
| @Test |
| public void testBoundedIntervalAndCumTimeWithReset() throws Exception { |
| BackOff backOff = |
| FluentBackoff.DEFAULT |
| .withInitialBackoff(Duration.millis(500)) |
| .withMaxBackoff(Duration.standardSeconds(1)) |
| .withMaxCumulativeBackoff(Duration.standardMinutes(1)) |
| .backoff(); |
| |
| assertThat(countMaximumBackoff(backOff), equalTo(Duration.standardMinutes(1).getMillis())); |
| |
| backOff.reset(); |
| assertThat(countMaximumBackoff(backOff), equalTo(Duration.standardMinutes(1).getMillis())); |
| // sanity check: should get 0 if we don't reset |
| assertThat(countMaximumBackoff(backOff), equalTo(0L)); |
| |
| backOff.reset(); |
| assertThat(countMaximumBackoff(backOff), equalTo(Duration.standardMinutes(1).getMillis())); |
| } |
| |
| /** Tests with bounded interval, custom exponent, limited cumulative time and retries. */ |
| @Test |
| public void testBoundedIntervalAndCumTimeAndRetriesWithReset() throws Exception { |
| BackOff backOff = |
| FluentBackoff.DEFAULT |
| .withInitialBackoff(Duration.millis(500)) |
| .withMaxBackoff(Duration.standardSeconds(1)) |
| .withMaxCumulativeBackoff(Duration.standardMinutes(1)) |
| .backoff(); |
| |
| long cumulativeBackoffMillis = 0; |
| long currentBackoffMillis = backOff.nextBackOffMillis(); |
| while (currentBackoffMillis != BackOff.STOP) { |
| cumulativeBackoffMillis += currentBackoffMillis; |
| currentBackoffMillis = backOff.nextBackOffMillis(); |
| } |
| assertThat(cumulativeBackoffMillis, equalTo(Duration.standardMinutes(1).getMillis())); |
| } |
| |
| @Test |
| public void testFluentBackoffToString() throws IOException { |
| FluentBackoff config = |
| FluentBackoff.DEFAULT |
| .withExponent(3.4) |
| .withMaxRetries(4) |
| .withInitialBackoff(Duration.standardSeconds(3)) |
| .withMaxBackoff(Duration.standardHours(1)) |
| .withMaxCumulativeBackoff(Duration.standardDays(1)); |
| |
| assertEquals( |
| "FluentBackoff{exponent=3.4, initialBackoff=PT3S, maxBackoff=PT3600S," |
| + " maxRetries=4, maxCumulativeBackoff=PT86400S}", |
| config.toString()); |
| } |
| |
| @Test |
| public void testBackoffImplToString() throws IOException { |
| FluentBackoff config = |
| FluentBackoff.DEFAULT |
| .withExponent(3.4) |
| .withMaxRetries(4) |
| .withInitialBackoff(Duration.standardSeconds(3)) |
| .withMaxBackoff(Duration.standardHours(1)) |
| .withMaxCumulativeBackoff(Duration.standardDays(1)); |
| BackOff backOff = config.backoff(); |
| |
| assertEquals( |
| "BackoffImpl{backoffConfig=" |
| + config.toString() |
| + "," |
| + " currentRetry=0, currentCumulativeBackoff=PT0S}", |
| backOff.toString()); |
| |
| // backoff once, ignoring result |
| backOff.nextBackOffMillis(); |
| |
| // currentRetry is exact, we can test it. |
| assertThat(backOff.toString(), containsString("currentRetry=1")); |
| // currentCumulativeBackoff is not exact; we cannot even check that it's non-zero (randomness). |
| } |
| } |