cmccabe commented on a change in pull request #10106: URL: https://github.com/apache/kafka/pull/10106#discussion_r574639391
########## File path: metadata/src/main/java/org/apache/kafka/metalog/metalog/MetaLogManager.java ########## @@ -0,0 +1,79 @@ +/* + * 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.kafka.metalog; + +import org.apache.kafka.metadata.ApiMessageAndVersion; + +import java.util.List; + +/** + * The MetaLogManager handles storing metadata and electing leaders. + */ +public interface MetaLogManager { + + /** + * Start this meta log manager. + * The manager must be ready to accept incoming calls after this function returns. + * It is an error to initialize a MetaLogManager more than once. + */ + void initialize() throws Exception; + + /** + * Register the listener. The manager must be initialized already. + * The listener must be ready to accept incoming calls immediately. + * + * @param listener The listener to register. + */ + void register(MetaLogListener listener) throws Exception; + + /** + * Schedule a write to the log. + * + * The write will be scheduled to happen at some time in the future. There is no + * error return or exception thrown if the write fails. Instead, the listener may + * regard the write as successful if and only if the MetaLogManager reaches the given + * index before renouncing its leadership. The listener should determine this by + * monitoring the committed indexes. + * + * @param epoch The controller epoch. + * @param batch The batch of messages to write. + * + * @return The index of the message. Review comment: Oh, this is another historical artifact, back when "index" was separate from "offset". Right now it should just be replaced with "offset." I will do that ---------------------------------------------------------------- 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: us...@infra.apache.org
