eric-maynard commented on code in PR #278: URL: https://github.com/apache/polaris/pull/278#discussion_r1772382706
########## polaris-service/src/test/java/org/apache/polaris/service/ratelimiter/TokenBucketRateLimiterTest.java: ########## @@ -0,0 +1,103 @@ +/* + * 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.polaris.service.ratelimiter; + +import java.time.Clock; +import java.time.Duration; +import java.time.Instant; +import java.time.ZoneOffset; +import java.util.concurrent.CountDownLatch; +import java.util.concurrent.ExecutorService; +import java.util.concurrent.Executors; +import java.util.concurrent.atomic.AtomicInteger; +import org.junit.jupiter.api.Assertions; +import org.junit.jupiter.api.Test; +import org.threeten.extra.MutableClock; + +/** Main unit test class for TokenBucketRateLimiter */ +public class TokenBucketRateLimiterTest { + @Test + void testBasic() { + MutableClock clock = MutableClock.of(Instant.now(), ZoneOffset.UTC); + clock.add(Duration.ofSeconds(5)); + + RateLimitResultAsserter asserter = + new RateLimitResultAsserter(new TokenBucketRateLimiter(10, 100, clock)); + + asserter.canAcquire(100); + asserter.cantAcquire(); + + clock.add(Duration.ofSeconds(1)); + asserter.canAcquire(10); + asserter.cantAcquire(); + + clock.add(Duration.ofSeconds(10)); + asserter.canAcquire(100); + asserter.cantAcquire(); + } + + /** + * Starts several threads that try to query the rate limiter at the same time, ensuring that we + * only allow "maxTokens" requests + */ + @Test + void testConcurrent() throws InterruptedException { + int maxTokens = 100; + int numTasks = 50000; + int tokensPerSecond = 10; // Can be anything above 0 + int sleepPerNThreads = 100; // Making this too low will result in the test taking a long time + int maxSleepMillis = 5; + + TokenBucketRateLimiter rl = + new TokenBucketRateLimiter( + tokensPerSecond, maxTokens, Clock.fixed(Instant.now(), ZoneOffset.UTC)); + AtomicInteger numAcquired = new AtomicInteger(); + CountDownLatch startLatch = new CountDownLatch(numTasks); + CountDownLatch endLatch = new CountDownLatch(numTasks); + + try (ExecutorService executor = Executors.newVirtualThreadPerTaskExecutor()) { + for (int i = 0; i < numTasks; i++) { + int i_ = i; + executor.submit( + () -> { + try { + // Enforce that tasks pause until all tasks are submitted + startLatch.countDown(); + startLatch.await(); + + // Make some threads sleep + if (i_ % sleepPerNThreads == 0) { + Thread.sleep((int) (Math.random() * (maxSleepMillis + 1))); Review Comment: I would still really prefer if we keep `sleep` out of the tests. The idea of using a countdown latch is that you can mock the passage of time by counting down on the latch and unblocking various threads at different "times". -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: commits-unsubscr...@polaris.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
