XComp commented on a change in pull request #14847: URL: https://github.com/apache/flink/pull/14847#discussion_r578581053
########## File path: flink-runtime/src/main/java/org/apache/flink/runtime/scheduler/StopWithSavepointContext.java ########## @@ -0,0 +1,197 @@ +/* + * 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.runtime.scheduler; + +import org.apache.flink.api.common.JobID; +import org.apache.flink.runtime.checkpoint.CheckpointCoordinator; +import org.apache.flink.runtime.execution.ExecutionState; +import org.apache.flink.util.FlinkException; +import org.apache.flink.util.Preconditions; + +import org.apache.commons.lang3.StringUtils; +import org.slf4j.Logger; + +import java.util.Collection; +import java.util.Set; +import java.util.concurrent.CompletableFuture; +import java.util.stream.Collectors; + +/** {@code StopWithSavepointContext} implements {@link StopWithSavepointOperations}. */ +public class StopWithSavepointContext implements StopWithSavepointOperations { + + private final Logger log; + + private final SchedulerBase scheduler; + private final CheckpointCoordinator checkpointCoordinator; + private final JobID jobId; + + private final CompletableFuture<String> result = new CompletableFuture<>(); + + private StopWithSavepointState state = StopWithSavepointState.InitialWait; + private String path; + private Set<ExecutionState> unfinishedStates; + + public StopWithSavepointContext(JobID jobId, SchedulerBase scheduler, Logger log) { + this.jobId = jobId; + this.scheduler = scheduler; + this.checkpointCoordinator = scheduler.getCheckpointCoordinator(); + this.log = log; + } + + @Override + public synchronized void handleSavepointCreation(String path, Throwable throwable) { + final StopWithSavepointState oldState = state; + state = state.onSavepointCreation(this, path, throwable); + + log.debug( + "Stop-with-savepoint transitioned from {} to {} on savepoint creation handling.", + oldState, + state); + } + + @Override + public synchronized void handleExecutionTermination( + Collection<ExecutionState> executionStates) { + final StopWithSavepointState oldState = state; + state = state.onExecutionsTermination(this, executionStates); + + log.debug( + "Stop-with-savepoint transitioned from {} to {} on execution termination handling.", + oldState, + state); + } + + @Override + public CompletableFuture<String> getResult() { + return result; + } + + private StopWithSavepointState terminateExceptionWithGlobalFailover( + Iterable<ExecutionState> unfinishedExecutionStates) { + String errorMessage = + String.format( + "Inconsistent execution state after stopping with savepoint. At least one execution is still in one of the following states: %s. A global fail-over is triggered to recover the job %s.", + StringUtils.join(unfinishedExecutionStates, ", "), jobId); + FlinkException inconsistentFinalStateException = new FlinkException(errorMessage); + + scheduler.handleGlobalFailure(inconsistentFinalStateException); + return terminateExceptionally(inconsistentFinalStateException); + } + + private StopWithSavepointState terminateExceptionally(Throwable throwable) { + scheduler.startCheckpointScheduler(checkpointCoordinator); + result.completeExceptionally(throwable); + + return StopWithSavepointState.Final; + } + + private StopWithSavepointState terminateSuccessfully(String path) { + result.complete(path); + + return StopWithSavepointState.Final; + } + + private static Set<ExecutionState> extractUnfinishedStates( + Collection<ExecutionState> executionStates) { + return executionStates.stream() + .filter(state -> state != ExecutionState.FINISHED) + .collect(Collectors.toSet()); + } + + /** + * {@code StopWithSavepointState} represents the different states during the stop-with-savepoint + * operation. + * + * <p>The state transitions are implemented in the following way: InitialWait -> + * [WaitForSavepointCreation|WaitForJobTermination] -> Final + */ + private enum StopWithSavepointState { + InitialWait { + @Override + protected StopWithSavepointState handleSavepointCreation( + StopWithSavepointContext context, String path) { + context.path = path; + return WaitForJobTermination; + } + + @Override + public StopWithSavepointState onExecutionsTermination( + StopWithSavepointContext context, Collection<ExecutionState> executionStates) { + context.unfinishedStates = extractUnfinishedStates(executionStates); + return WaitForSavepointCreation; + } + }, + WaitForSavepointCreation { + @Override + public StopWithSavepointState handleSavepointCreation( + StopWithSavepointContext context, String path) { + Preconditions.checkState( + context.unfinishedStates != null, + InitialWait + " should have preceded: No unfinishedStates is set."); + + if (!context.unfinishedStates.isEmpty()) { + return context.terminateExceptionWithGlobalFailover(context.unfinishedStates); + } + + return context.terminateSuccessfully(path); + } + }, + WaitForJobTermination { + @Override + public StopWithSavepointState onExecutionsTermination( + StopWithSavepointContext context, Collection<ExecutionState> executionStates) { Review comment: I refactored it to use classes now. 👍 ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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