rmetzger commented on a change in pull request #13217: URL: https://github.com/apache/flink/pull/13217#discussion_r475665594
########## File path: flink-runtime/src/main/java/org/apache/flink/runtime/dispatcher/DispatcherJob.java ########## @@ -0,0 +1,242 @@ +/* + * 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.dispatcher; + +import org.apache.flink.api.common.JobID; +import org.apache.flink.api.common.JobStatus; +import org.apache.flink.api.common.time.Time; +import org.apache.flink.runtime.concurrent.FutureUtils; +import org.apache.flink.runtime.execution.ExecutionState; +import org.apache.flink.runtime.executiongraph.ArchivedExecutionGraph; +import org.apache.flink.runtime.jobmaster.JobManagerRunner; +import org.apache.flink.runtime.jobmaster.JobMasterGateway; +import org.apache.flink.runtime.messages.Acknowledge; +import org.apache.flink.runtime.messages.webmonitor.JobDetails; +import org.apache.flink.runtime.rpc.RpcUtils; +import org.apache.flink.util.AutoCloseableAsync; +import org.apache.flink.util.Preconditions; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import javax.annotation.concurrent.GuardedBy; + +import java.util.concurrent.CompletableFuture; + +/** + * Abstraction used by the {@link Dispatcher} to manage JobManagers, in + * particular during initialization. + * While a job is initializing, the JobMasterGateway is not available. A small subset + * of the methods of the JobMasterGateway necessary during initialization are provided + * by this class (job details, cancel). + */ +public final class DispatcherJob implements AutoCloseableAsync { + + private final Logger log = LoggerFactory.getLogger(DispatcherJob.class); + + private final CompletableFuture<JobManagerRunner> jobManagerRunnerFuture; + private final CompletableFuture<ArchivedExecutionGraph> jobResultFuture; + + private final long initializationTimestamp; + private final JobID jobId; + private final String jobName; + + private final Object lock = new Object(); + + // internal field to track job status during initialization. Is not updated anymore after + // job is initialized, cancelled or failed. + @GuardedBy("lock") + private JobStatus jobStatus = JobStatus.INITIALIZING; + + private final CompletableFuture<Void> terminationFuture = new CompletableFuture<>(); + + private enum SubmissionType { + INITIAL, RECOVERY + } + + static DispatcherJob createForSubmission( + CompletableFuture<JobManagerRunner> jobManagerRunnerFuture, + JobID jobId, + String jobName, + long initializationTimestamp) { + return new DispatcherJob(jobManagerRunnerFuture, jobId, jobName, initializationTimestamp, SubmissionType.INITIAL); + } + + static DispatcherJob createForRecovery( + CompletableFuture<JobManagerRunner> jobManagerRunnerFuture, + JobID jobId, + String jobName, + long initializationTimestamp) { + return new DispatcherJob(jobManagerRunnerFuture, jobId, jobName, initializationTimestamp, SubmissionType.RECOVERY); + } + + private DispatcherJob( + CompletableFuture<JobManagerRunner> jobManagerRunnerFuture, + JobID jobId, + String jobName, + long initializationTimestamp, + SubmissionType submissionType) { + this.jobManagerRunnerFuture = jobManagerRunnerFuture; + this.jobId = jobId; + this.jobName = jobName; + this.initializationTimestamp = initializationTimestamp; + this.jobResultFuture = new CompletableFuture<>(); + + FutureUtils.assertNoException(this.jobManagerRunnerFuture.handle((jobManagerRunner, throwable) -> { + // JM has been initialized, or the initialization failed + synchronized (lock) { + if (throwable == null) { + // Forward result future + FutureUtils.forward(jobManagerRunner.getResultFuture(), jobResultFuture); + + if (jobStatus == JobStatus.CANCELLING) { + log.info("Cancellation during initialization has been requested for job {}. Initialization completed, cancelling job.", jobId); + + // cancel job + jobManagerRunner + .getJobMasterGateway() + .thenCompose(gw -> gw.cancel(RpcUtils.INF_TIMEOUT)) + .whenComplete((ignored, cancelThrowable) -> { + if (cancelThrowable != null) { + log.warn("Cancellation of job {} failed", jobId, cancelThrowable); + } + }); + + // cancellation will eventually complete the jobResultFuture + jobResultFuture.whenComplete((archivedExecutionGraph, resultThrowable) -> { + synchronized (lock) { + if (resultThrowable == null) { + jobStatus = archivedExecutionGraph.getState(); + } else { + jobStatus = JobStatus.FAILED; + } + } + }); + } else { + jobStatus = JobStatus.RUNNING; // this status should never be exposed from the DispatcherJob. Only used internally for tracking running state + } + } else { // failure during initialization + if (submissionType == SubmissionType.RECOVERY) { + jobResultFuture.completeExceptionally(throwable); + } else { + jobResultFuture.complete(ArchivedExecutionGraph.createFromInitializingJob( + jobId, + jobName, + throwable, + JobStatus.FAILED, + initializationTimestamp)); + } + } + } + return null; + })); + } + + public CompletableFuture<ArchivedExecutionGraph> getResultFuture() { + return jobResultFuture; + } + + public CompletableFuture<JobDetails> requestJobDetails(Time timeout) { + synchronized (lock) { + if (isRunning()) { + return getJobMasterGateway().thenCompose(jobMasterGateway -> jobMasterGateway.requestJobDetails( + timeout)); + } else { + int[] tasksPerState = new int[ExecutionState.values().length]; + return CompletableFuture.completedFuture(new JobDetails( + jobId, + jobName, + initializationTimestamp, + 0, + 0, + jobStatus, + 0, + tasksPerState, + 0)); + } + } + } + + public CompletableFuture<Acknowledge> cancel(Time timeout) { + synchronized (lock) { + if (isRunning()) { + return getJobMasterGateway().thenCompose(jobMasterGateway -> jobMasterGateway.cancel(timeout)); + } else { + log.info("Cancellation during initialization requested for job {}. Job will be cancelled once JobManager has been initialized.", jobId); + jobStatus = JobStatus.CANCELLING; + return jobResultFuture.thenApply(ignored -> Acknowledge.get()); + } + } + } + + public CompletableFuture<JobStatus> requestJobStatus(Time timeout) { + synchronized (lock) { + if (isRunning()) { + return getJobMasterGateway().thenCompose(jobMasterGateway -> jobMasterGateway.requestJobStatus(timeout)); + } else { + return CompletableFuture.completedFuture(jobStatus); + } + } + } + + public CompletableFuture<ArchivedExecutionGraph> requestJob(Time timeout) { + synchronized (lock) { + if (isRunning()) { + return getJobMasterGateway().thenCompose(jobMasterGateway -> jobMasterGateway.requestJob(timeout)); + } else { + return CompletableFuture.supplyAsync(() -> ArchivedExecutionGraph.createFromInitializingJob(jobId, jobName, null, jobStatus, initializationTimestamp)); + } Review comment: I think it will return the right result, but the naming of methods / variables here is terrible: `jobStatus == JobStatus.RUNNING` as soon as the `jobManagerRunnerFuture` completed. The job is not necessarily in RUNNING state. It could be in `CREATED` or `FAILING` ... we would still do the correct thing in `DispatcherJob`, but it is not very obvious. I will improve the tracking of the job status inside the `DispatcherJob`, in particular the names (this seems to be the biggest flaw of my proposed changes). ---------------------------------------------------------------- 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
