dawidwys commented on a change in pull request #15313: URL: https://github.com/apache/flink/pull/15313#discussion_r601469871
########## File path: flink-streaming-java/src/main/java/org/apache/flink/streaming/runtime/io/checkpointing/BarrierHandlerAction.java ########## @@ -0,0 +1,66 @@ +/* + * 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.streaming.runtime.io.checkpointing; + +import org.apache.flink.runtime.checkpoint.CheckpointException; +import org.apache.flink.runtime.checkpoint.channel.InputChannelInfo; +import org.apache.flink.runtime.io.network.api.CheckpointBarrier; + +import java.io.IOException; + +/** + * Represents a state in a state machine of processing a checkpoint. There are 4 base states: + * + * <ul> + * <li>Waiting for an aligned barrier + * <li>Collecting aligned barriers + * <li>Waiting for an unaligned barrier + * <li>Collecting unaligned barriers + * </ul> + * + * <p>Additionally depending on the configuration we can switch between aligned and unaligned + * actions. + */ +interface BarrierHandlerAction { + BarrierHandlerAction alignmentTimeout(Context context, CheckpointBarrier checkpointBarrier) + throws IOException, CheckpointException; + + BarrierHandlerAction announcementReceived( + Context context, InputChannelInfo channelInfo, int sequenceNumber) throws IOException; + + BarrierHandlerAction barrierReceived( + Context context, InputChannelInfo channelInfo, CheckpointBarrier checkpointBarrier) + throws IOException, CheckpointException; + + BarrierHandlerAction abort(long cancelledId) throws IOException; + + /** + * An entry point for communication between {@link BarrierHandlerAction} and {@link + * SingleCheckpointBarrierHandler}. + */ + interface Context { + boolean allBarriersReceived(); + + void triggerGlobalCheckpoint(CheckpointBarrier checkpointBarrier) throws IOException; + + void triggerTaskCheckpoint(CheckpointBarrier checkpointBarrier) throws CheckpointException; Review comment: sure, can rename them. However I don't like the `initCheckpoint` name. We should call it only for `unaligned` checkpoints to initialise checkpoints in input channels. `initCheckpoint` could indicate it should be called in case of aligned checkpoints as well. How about `initInputsCheckpoint(ing)`? -- 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]
