schongloo commented on code in PR #969: URL: https://github.com/apache/flink-kubernetes-operator/pull/969#discussion_r2353002199
########## flink-kubernetes-operator/src/main/java/org/apache/flink/kubernetes/operator/controller/bluegreen/BlueGreenDeploymentService.java: ########## @@ -0,0 +1,659 @@ +/* + * 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.kubernetes.operator.controller.bluegreen; + +import org.apache.flink.api.common.JobStatus; +import org.apache.flink.kubernetes.operator.api.FlinkBlueGreenDeployment; +import org.apache.flink.kubernetes.operator.api.FlinkDeployment; +import org.apache.flink.kubernetes.operator.api.bluegreen.BlueGreenDeploymentType; +import org.apache.flink.kubernetes.operator.api.bluegreen.BlueGreenDiffType; +import org.apache.flink.kubernetes.operator.api.status.FlinkBlueGreenDeploymentState; +import org.apache.flink.kubernetes.operator.api.status.Savepoint; +import org.apache.flink.kubernetes.operator.api.status.SavepointFormatType; +import org.apache.flink.kubernetes.operator.api.status.SnapshotTriggerType; +import org.apache.flink.kubernetes.operator.config.KubernetesOperatorConfigOptions; +import org.apache.flink.kubernetes.operator.controller.FlinkBlueGreenDeployments; +import org.apache.flink.kubernetes.operator.controller.FlinkResourceContext; +import org.apache.flink.kubernetes.operator.utils.bluegreen.BlueGreenUtils; +import org.apache.flink.util.Preconditions; + +import io.fabric8.kubernetes.api.model.ObjectMeta; +import io.javaoperatorsdk.operator.api.reconciler.UpdateControl; +import lombok.AllArgsConstructor; +import lombok.Getter; +import org.jetbrains.annotations.NotNull; +import org.jetbrains.annotations.Nullable; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.time.Instant; + +import static org.apache.flink.kubernetes.operator.controller.bluegreen.BlueGreenKubernetesService.deleteFlinkDeployment; +import static org.apache.flink.kubernetes.operator.controller.bluegreen.BlueGreenKubernetesService.deployCluster; +import static org.apache.flink.kubernetes.operator.controller.bluegreen.BlueGreenKubernetesService.isFlinkDeploymentReady; +import static org.apache.flink.kubernetes.operator.controller.bluegreen.BlueGreenKubernetesService.suspendFlinkDeployment; +import static org.apache.flink.kubernetes.operator.utils.bluegreen.BlueGreenUtils.fetchSavepointInfo; +import static org.apache.flink.kubernetes.operator.utils.bluegreen.BlueGreenUtils.getReconciliationReschedInterval; +import static org.apache.flink.kubernetes.operator.utils.bluegreen.BlueGreenUtils.getSpecDiff; +import static org.apache.flink.kubernetes.operator.utils.bluegreen.BlueGreenUtils.hasSpecChanged; +import static org.apache.flink.kubernetes.operator.utils.bluegreen.BlueGreenUtils.instantStrToMillis; +import static org.apache.flink.kubernetes.operator.utils.bluegreen.BlueGreenUtils.isSavepointRequired; +import static org.apache.flink.kubernetes.operator.utils.bluegreen.BlueGreenUtils.millisToInstantStr; +import static org.apache.flink.kubernetes.operator.utils.bluegreen.BlueGreenUtils.prepareFlinkDeployment; +import static org.apache.flink.kubernetes.operator.utils.bluegreen.BlueGreenUtils.setLastReconciledSpec; +import static org.apache.flink.kubernetes.operator.utils.bluegreen.BlueGreenUtils.triggerSavepoint; + +/** Consolidated service for all Blue/Green deployment operations. */ +public class BlueGreenDeploymentService { + + private static final Logger LOG = LoggerFactory.getLogger(BlueGreenDeploymentService.class); + private static final long RETRY_DELAY_MS = 500; + + // ==================== Deployment Initiation Methods ==================== + + /** + * Initiates a new Blue/Green deployment. + * + * @param context the transition context + * @param nextBlueGreenDeploymentType the type of deployment to create + * @param nextState the next state to transition to + * @param lastCheckpoint the checkpoint to restore from (can be null) + * @param isFirstDeployment whether this is the first deployment + * @return UpdateControl for the deployment + */ + public UpdateControl<FlinkBlueGreenDeployment> initiateDeployment( + BlueGreenContext context, + BlueGreenDeploymentType nextBlueGreenDeploymentType, + FlinkBlueGreenDeploymentState nextState, + Savepoint lastCheckpoint, + boolean isFirstDeployment) { + ObjectMeta bgMeta = context.getBgDeployment().getMetadata(); + + FlinkDeployment flinkDeployment = + prepareFlinkDeployment( + context, + nextBlueGreenDeploymentType, + lastCheckpoint, + isFirstDeployment, + bgMeta); + + deployCluster(context, flinkDeployment); + + BlueGreenUtils.setAbortTimestamp(context); + + return patchStatusUpdateControl(context, nextState, JobStatus.RECONCILING, null) + .rescheduleAfter(BlueGreenUtils.getReconciliationReschedInterval(context)); + } + + /** + * Checks if a full transition can be initiated and initiates it if conditions are met. + * + * @param context the transition context + * @param currentBlueGreenDeploymentType the current deployment type + * @return UpdateControl for the deployment + */ + public UpdateControl<FlinkBlueGreenDeployment> checkAndInitiateDeployment( + BlueGreenContext context, BlueGreenDeploymentType currentBlueGreenDeploymentType) { + BlueGreenDiffType specDiff = getSpecDiff(context); + + if (specDiff != BlueGreenDiffType.IGNORE) { + FlinkDeployment currentFlinkDeployment = + context.getDeploymentByType(currentBlueGreenDeploymentType); + + if (isFlinkDeploymentReady(currentFlinkDeployment)) { + if (specDiff == BlueGreenDiffType.TRANSITION) { + boolean savepointTriggered = false; + try { + savepointTriggered = handleSavepoint(context, currentFlinkDeployment); + } catch (Exception e) { + var error = "Could not trigger Savepoint. Details: " + e.getMessage(); + return markDeploymentFailing(context, error); + } + + if (savepointTriggered) { + // Spec is intentionally not marked as reconciled here to allow + // reprocessing the TRANSITION once savepoint creation completes + var savepointingState = + calculateSavepointingState(currentBlueGreenDeploymentType); + return patchStatusUpdateControl(context, savepointingState, null, null) + .rescheduleAfter(getReconciliationReschedInterval(context)); + } + + setLastReconciledSpec(context); + try { + return startTransition( + context, currentBlueGreenDeploymentType, currentFlinkDeployment); + } catch (Exception e) { + var error = "Could not start Transition. Details: " + e.getMessage(); + context.getDeploymentStatus().setSavepointTriggerId(null); + return markDeploymentFailing(context, error); + } + } else { + setLastReconciledSpec(context); + LOG.info( + "Patching FlinkDeployment '{}' during checkAndInitiateDeployment", + currentFlinkDeployment.getMetadata().getName()); + return patchFlinkDeployment(context, currentBlueGreenDeploymentType); + } + } else { + if (context.getDeploymentStatus().getJobStatus().getState() != JobStatus.FAILING) { + setLastReconciledSpec(context); + var error = + String.format( + "Transition to %s not possible, current Flink Deployment '%s' is not READY. FAILING '%s'", + calculateTransition(currentBlueGreenDeploymentType) + .nextBlueGreenDeploymentType, + currentFlinkDeployment.getMetadata().getName(), + context.getBgDeployment().getMetadata().getName()); + return markDeploymentFailing(context, error); + } + } + } + + return UpdateControl.noUpdate(); + } + + private UpdateControl<FlinkBlueGreenDeployment> patchFlinkDeployment( + BlueGreenContext context, BlueGreenDeploymentType blueGreenDeploymentTypeToPatch) { + + String childDeploymentName = + context.getBgDeployment().getMetadata().getName() + + "-" + + blueGreenDeploymentTypeToPatch.toString().toLowerCase(); + + // We want to patch, therefore the transition should point to the existing deployment + // details + var patchingState = calculatePatchingState(blueGreenDeploymentTypeToPatch); + + // If we're not transitioning between deployments, mark as a single deployment to have it + // not wait for synchronization + var isFirstDeployment = context.getDeployments().getNumberOfDeployments() != 2; + + // TODO: if the resource failed right after being deployed with an initialSavepointPath, + // will it be used by this patching? otherwise this is unnecessary, keep lastSavepoint = + // null. + Savepoint lastSavepoint = + carryOverSavepoint(context, blueGreenDeploymentTypeToPatch, childDeploymentName); + + return initiateDeployment( + context, + blueGreenDeploymentTypeToPatch, + patchingState, + lastSavepoint, + isFirstDeployment); + } + + @Nullable + private static Savepoint carryOverSavepoint( + BlueGreenContext context, + BlueGreenDeploymentType blueGreenDeploymentTypeToPatch, + String childDeploymentName) { + var deploymentToPatch = context.getDeploymentByType(blueGreenDeploymentTypeToPatch); + var initialSavepointPath = deploymentToPatch.getSpec().getJob().getInitialSavepointPath(); + + if (initialSavepointPath == null || initialSavepointPath.isEmpty()) { + initialSavepointPath = + deploymentToPatch.getStatus().getJobStatus().getUpgradeSavepointPath(); + } + + Savepoint lastSavepoint = null; + if (initialSavepointPath != null && !initialSavepointPath.isEmpty()) { + var ctx = + context.getCtxFactory() + .getResourceContext(deploymentToPatch, context.getJosdkContext()); + + lastSavepoint = getSavepointObject(ctx, initialSavepointPath); + + LOG.info( + "Patching FlinkDeployment '{}', carrying over Savepoint at: '{}'", + childDeploymentName, + initialSavepointPath); + } else { + LOG.info("Patching FlinkDeployment '{}'", childDeploymentName); + } + + return lastSavepoint; + } + + private UpdateControl<FlinkBlueGreenDeployment> startTransition( + BlueGreenContext context, + BlueGreenDeploymentType currentBlueGreenDeploymentType, + FlinkDeployment currentFlinkDeployment) { + DeploymentTransition transition = calculateTransition(currentBlueGreenDeploymentType); + + Savepoint lastCheckpoint = configureInitialSavepoint(context, currentFlinkDeployment); + + return initiateDeployment( + context, + transition.nextBlueGreenDeploymentType, + transition.nextState, + lastCheckpoint, + false); + } + + private DeploymentTransition calculateTransition(BlueGreenDeploymentType currentType) { + if (BlueGreenDeploymentType.BLUE == currentType) { + return new DeploymentTransition( + BlueGreenDeploymentType.GREEN, + FlinkBlueGreenDeploymentState.TRANSITIONING_TO_GREEN); + } else { + return new DeploymentTransition( + BlueGreenDeploymentType.BLUE, + FlinkBlueGreenDeploymentState.TRANSITIONING_TO_BLUE); + } + } + + private FlinkBlueGreenDeploymentState calculatePatchingState( + BlueGreenDeploymentType currentType) { + if (BlueGreenDeploymentType.BLUE == currentType) { + return FlinkBlueGreenDeploymentState.TRANSITIONING_TO_BLUE; + } else { + return FlinkBlueGreenDeploymentState.TRANSITIONING_TO_GREEN; + } + } + + // ==================== Savepointing Methods ==================== + + public boolean monitorSavepoint( + BlueGreenContext context, BlueGreenDeploymentType currentBlueGreenDeploymentType) { + + FlinkResourceContext<FlinkDeployment> ctx = + context.getCtxFactory() + .getResourceContext( + context.getDeploymentByType(currentBlueGreenDeploymentType), + context.getJosdkContext()); + + String savepointTriggerId = context.getDeploymentStatus().getSavepointTriggerId(); + var savepointFetchResult = fetchSavepointInfo(ctx, savepointTriggerId); + + return !savepointFetchResult.isPending(); + } + + private Savepoint configureInitialSavepoint( + BlueGreenContext context, FlinkDeployment currentFlinkDeployment) { + // Create savepoint for all upgrade modes except STATELESS + // (originally only SAVEPOINT mode required savepoints) + if (isSavepointRequired(context)) { + FlinkResourceContext<FlinkDeployment> ctx = + context.getCtxFactory() + .getResourceContext(currentFlinkDeployment, context.getJosdkContext()); + + String triggerId = context.getDeploymentStatus().getSavepointTriggerId(); + var savepointFetchResult = fetchSavepointInfo(ctx, triggerId); + + if (savepointFetchResult.getError() != null + && !savepointFetchResult.getError().isEmpty()) { + throw new RuntimeException( + String.format( + "Could not fetch savepoint with triggerId: %s. Error: %s", + triggerId, savepointFetchResult.getError())); + } + + return getSavepointObject(ctx, savepointFetchResult.getLocation()); + } + + // Currently not using last checkpoint recovery for LAST_STATE upgrade mode Review Comment: We realized using checkpoints to preserve state across Blue/Green transitions can be a brittle strategy since it would depend entirely on the users configuration (whether they're even enabled or not, externally retained, for how long, etc.). So we opted to go for Savepoints instead, at least initially. -- 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. To unsubscribe, e-mail: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
