jolshan commented on code in PR #13638: URL: https://github.com/apache/kafka/pull/13638#discussion_r1183155377
########## group-coordinator/src/main/java/org/apache/kafka/coordinator/group/consumer/CurrentAssignmentBuilder.java: ########## @@ -0,0 +1,415 @@ +/* + * 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.coordinator.group.consumer; + +import org.apache.kafka.common.Uuid; +import org.apache.kafka.common.message.ConsumerGroupHeartbeatRequestData; + +import java.util.Collections; +import java.util.HashMap; +import java.util.HashSet; +import java.util.Iterator; +import java.util.List; +import java.util.Map; +import java.util.Objects; +import java.util.Set; +import java.util.function.BiFunction; + +/** + * The CurrentAssignmentBuilder class encapsulates the reconciliation engine of the + * consumer group protocol. Given the current state of a member and a desired or target + * assignment state, the state machine takes the necessary steps to converge them. + * + * The member state has the following properties: + * - Current Epoch - The current epoch of the member. + * - Next Epoch - The desired epoch of the member. It corresponds to the epoch of + * the target/desired assignment. The member transitions to this epoch + * when it has revoked the partitions that it does not own or if it + * does not have to revoke any. + * - Previous Epoch - The previous epoch of the member when the state was updated. Review Comment: I'm assuming this isn't current epoch -1 but instead the epoch for when the member last updated? Likewise, next epoch is not current epoch + 1? -- 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: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
