xintongsong commented on a change in pull request #8952: URL: https://github.com/apache/flink/pull/8952#discussion_r547804386
########## File path: flink-runtime/src/main/java/org/apache/flink/runtime/failurerate/FailureRater.java ########## @@ -0,0 +1,49 @@ +/* + * 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.flink.runtime.failurerate; + +import org.apache.flink.metrics.Meter; +import org.apache.flink.util.clock.Clock; + +/** + * Failure rate interface. + */ +public interface FailureRater extends Meter { Review comment: I think convenience of testing should not decide the contract of a production interface. However, we do want to implement the interface in a testing-friendly way. In this particular case, I believe mocking of time can be achieved in something like the following. ``` public class TimestampBasedFailureRater implements ThresholdMeter { private final Supplier<Long> currentTimeMillisSupplier; public TimestampBasedFailureRater() { this.currentTimeMillisSupplier = System::currentTimeMillis; } @VisibleForTesting public TimestampBasedFailureRater(Supplier<Long> customSupplier) { this.currentTimeMillisSupplier = checkNotNull(customSupplier); } public void markEvent() { long eventTimeStamp = currentTimeMillisSupplier.get(); } } ``` As for rate per minute, we can easily extend `Meter` with a `getRatePerMinute`. ``` public interface Meter extend Metric { double getRate(); default double getRatePerMinute { return getRate() * 60.0; } } ``` ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected]
