vigyasharma commented on code in PR #14458: URL: https://github.com/apache/lucene/pull/14458#discussion_r2037483241
########## lucene/core/src/java/org/apache/lucene/index/KeepLastNCommitsDeletionPolicy.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.lucene.index; + +import java.io.IOException; +import java.util.List; + +/** + * This {@link IndexDeletionPolicy} implementation keeps the last N commits and removes all prior + * commits after a new commit is done. This policy can be useful for maintaining a history of recent + * commits while still managing index size. + */ +public class KeepLastNCommitsDeletionPolicy extends IndexDeletionPolicy { + + private final int numCommitsToKeep; + + /** + * Constructor that sets the number of commits to keep. + * + * @param numCommitsToKeep the number of most recent commits to retain + * @throws IllegalArgumentException if numCommitsToKeep is not positive + */ + public KeepLastNCommitsDeletionPolicy(int numCommitsToKeep) { + if (numCommitsToKeep <= 0) { + throw new IllegalArgumentException("number of recent commits to keep must be positive"); + } Review Comment: Thanks! It is critical that we don't accept `0 numCommitsToKeep`, otherwise the policy will simply delete all commits i.e. the entire index! Let's also add a test to ensure people get warned if they inadvertently remove this check. -- 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: issues-unsubscr...@lucene.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org
