congbobo184 commented on a change in pull request #8256: URL: https://github.com/apache/pulsar/pull/8256#discussion_r511551054
########## File path: pulsar-broker/src/main/java/org/apache/pulsar/broker/transaction/pendingack/PendingAckHandle.java ########## @@ -0,0 +1,81 @@ +/** + * 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.pulsar.broker.transaction.pendingack; + +import org.apache.bookkeeper.mledger.Position; +import org.apache.bookkeeper.mledger.impl.PositionImpl; +import org.apache.pulsar.broker.service.Consumer; +import org.apache.pulsar.broker.service.persistent.PersistentSubscription; +import org.apache.pulsar.client.api.transaction.TxnID; +import org.apache.pulsar.common.api.proto.PulsarApi; + +import java.util.List; +import java.util.Map; +import java.util.concurrent.CompletableFuture; + +public interface PendingAckHandle { + + /** + * Acknowledge message(s) for an ongoing transaction. + * <p> + * It can be of {@link PulsarApi.CommandAck.AckType#Individual} or {@link PulsarApi.CommandAck.AckType#Cumulative}. Single messages acked by ongoing + * transaction will be put in pending_ack state and only marked as deleted after transaction is committed. + * <p> + * Only one transaction is allowed to do cumulative ack on a subscription at a given time. + * If a transaction do multiple cumulative ack, only the one with largest position determined by + * {@link PositionImpl#compareTo(PositionImpl)} will be kept as it cover all position smaller than it. Review comment: for a moment, we only ensure one transaction can cumulative ack multiple times. if we only ensure cumulative ack position is greater than the old one, when the client disconnect, broker will dispatch the new message rather than the position witch was cumulative ack by the previous transaction. so, it has't consume the position with pervious transaction when the transaction abort. ---------------------------------------------------------------- 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]
