XComp commented on a change in pull request #14847: URL: https://github.com/apache/flink/pull/14847#discussion_r578584522
########## 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) { + Preconditions.checkState( + context.path != null, + InitialWait + " should have preceded: No path is set."); + + Collection<ExecutionState> unfinishedExecutionStates = + extractUnfinishedStates(executionStates); + if (!unfinishedExecutionStates.isEmpty()) { + return context.terminateExceptionWithGlobalFailover(unfinishedExecutionStates); + } + + return context.terminateSuccessfully(context.path); + } + }, + Final; + + public StopWithSavepointState onSavepointCreation( + StopWithSavepointContext context, String path, Throwable throwable) { + if (throwable != null) { + return context.terminateExceptionally(throwable); + } + + return handleSavepointCreation(context, path); + } + + protected StopWithSavepointState handleSavepointCreation( + StopWithSavepointContext context, String path) { + throw new IllegalStateException( + "No onSavepointCreation should have been called in " + this.name() + " state."); + } + + public StopWithSavepointState onExecutionsTermination( + StopWithSavepointContext context, Collection<ExecutionState> executionStates) { + throw new IllegalStateException( + "No onExecutionsTermination should have been called in " + + this.name() + + " state."); + } Review comment: You're right. I added all possible test cases to the most recent code version. ---------------------------------------------------------------- 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
