| // Copyright (C) 2019 The Android Open Source Project |
| // |
| // Licensed 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. |
| // Copyright (C) 2018 The Android Open Source Project |
| // |
| // Licensed 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 com.googlesource.gerrit.plugins.multisite.validation; |
| |
| import com.google.common.flogger.FluentLogger; |
| import com.google.gerrit.server.events.RefReceivedEvent; |
| import com.google.gerrit.server.git.GitRepositoryManager; |
| import com.google.gerrit.server.git.validators.RefOperationValidationListener; |
| import com.google.gerrit.server.git.validators.ValidationMessage; |
| import com.google.gerrit.server.validators.ValidationException; |
| import com.google.inject.Inject; |
| import com.googlesource.gerrit.plugins.multisite.validation.dfsrefdb.SharedRefDatabase; |
| import java.io.IOException; |
| import java.util.Collections; |
| import java.util.List; |
| import org.eclipse.jgit.lib.Ref; |
| import org.eclipse.jgit.lib.Repository; |
| |
| /** |
| * Validates if a change can be applied without bringing the system into a split brain situation by |
| * verifying that the local status is aligned with the central status as retrieved by the |
| * SharedRefDatabase. It also updates the DB to set the new current status for a ref as a |
| * consequence of ref updates, creation and deletions. The operation is done for mutable updates |
| * only. Operation on immutable ones are always considered valid. |
| */ |
| public class InSyncChangeValidator implements RefOperationValidationListener { |
| private static final FluentLogger logger = FluentLogger.forEnclosingClass(); |
| |
| private final SharedRefDatabase dfsRefDatabase; |
| private final GitRepositoryManager repoManager; |
| |
| @Inject |
| public InSyncChangeValidator(SharedRefDatabase dfsRefDatabase, GitRepositoryManager repoManager) { |
| this.dfsRefDatabase = dfsRefDatabase; |
| this.repoManager = repoManager; |
| } |
| |
| @Override |
| public List<ValidationMessage> onRefOperation(RefReceivedEvent refEvent) |
| throws ValidationException { |
| logger.atFine().log("Validating operation %s", refEvent); |
| |
| if (isImmutableRef(refEvent.getRefName())) { |
| return Collections.emptyList(); |
| } |
| |
| try (Repository repo = repoManager.openRepository(refEvent.getProjectNameKey())) { |
| |
| switch (refEvent.command.getType()) { |
| case CREATE: |
| return onCreateRef(refEvent); |
| |
| case UPDATE: |
| case UPDATE_NONFASTFORWARD: |
| return onUpdateRef(repo, refEvent); |
| |
| case DELETE: |
| return onDeleteRef(repo, refEvent); |
| |
| default: |
| throw new IllegalArgumentException( |
| String.format( |
| "Unsupported command type '%s', in event %s", |
| refEvent.command.getType().name(), refEvent)); |
| } |
| } catch (IOException e) { |
| throw new ValidationException( |
| "Unable to access repository " + refEvent.getProjectNameKey(), e); |
| } |
| } |
| |
| private boolean isImmutableRef(String refName) { |
| return refName.startsWith("refs/changes") && !refName.endsWith("/meta"); |
| } |
| |
| private List<ValidationMessage> onDeleteRef(Repository repo, RefReceivedEvent refEvent) |
| throws ValidationException { |
| try { |
| Ref localRef = repo.findRef(refEvent.getRefName()); |
| if (localRef == null) { |
| logger.atWarning().log( |
| "Local status inconsistent with shared ref database for ref %s. " |
| + "Trying to delete it but it is not in the local DB", |
| refEvent.getRefName()); |
| |
| throw new ValidationException( |
| String.format( |
| "Unable to delete ref '%s', cannot find it in the local ref database", |
| refEvent.getRefName())); |
| } |
| |
| if (!dfsRefDatabase.compareAndRemove(refEvent.getProjectNameKey().get(), localRef)) { |
| throw new ValidationException( |
| String.format( |
| "Unable to delete ref '%s', the local ObjectId '%s' is not equal to the one " |
| + "in the shared ref database", |
| refEvent.getRefName(), localRef.getObjectId().getName())); |
| } |
| } catch (IOException ioe) { |
| logger.atSevere().withCause(ioe).log( |
| "Local status inconsistent with shared ref database for ref %s. " |
| + "Trying to delete it but it is not in the DB", |
| refEvent.getRefName()); |
| |
| throw new ValidationException( |
| String.format( |
| "Unable to delete ref '%s', cannot find it in the shared ref database", |
| refEvent.getRefName()), |
| ioe); |
| } |
| return Collections.emptyList(); |
| } |
| |
| private List<ValidationMessage> onUpdateRef(Repository repo, RefReceivedEvent refEvent) |
| throws ValidationException { |
| try { |
| Ref localRef = repo.findRef(refEvent.getRefName()); |
| if (localRef == null) { |
| logger.atWarning().log( |
| "Local status inconsistent with shared ref database for ref %s. " |
| + "Trying to update it but it is not in the local DB", |
| refEvent.getRefName()); |
| |
| throw new ValidationException( |
| String.format( |
| "Unable to update ref '%s', cannot find it in the local ref database", |
| refEvent.getRefName())); |
| } |
| |
| Ref newRef = dfsRefDatabase.newRef(refEvent.getRefName(), refEvent.command.getNewId()); |
| if (!dfsRefDatabase.compareAndPut(refEvent.getProjectNameKey().get(), localRef, newRef)) { |
| throw new ValidationException( |
| String.format( |
| "Unable to update ref '%s', the local objectId '%s' is not equal to the one " |
| + "in the shared ref database", |
| refEvent.getRefName(), localRef.getObjectId().getName())); |
| } |
| } catch (IOException ioe) { |
| logger.atSevere().withCause(ioe).log( |
| "Local status inconsistent with shared ref database for ref %s. " |
| + "Trying to update it cannot extract the existing one on DB", |
| refEvent.getRefName()); |
| |
| throw new ValidationException( |
| String.format( |
| "Unable to update ref '%s', cannot open the local ref on the local DB", |
| refEvent.getRefName()), |
| ioe); |
| } |
| |
| return Collections.emptyList(); |
| } |
| |
| private List<ValidationMessage> onCreateRef(RefReceivedEvent refEvent) |
| throws ValidationException { |
| try { |
| Ref newRef = dfsRefDatabase.newRef(refEvent.getRefName(), refEvent.command.getNewId()); |
| dfsRefDatabase.compareAndCreate(refEvent.getProjectNameKey().get(), newRef); |
| } catch (IllegalArgumentException | IOException alreadyInDB) { |
| logger.atSevere().withCause(alreadyInDB).log( |
| "Local status inconsistent with shared ref database for ref %s. " |
| + "Trying to delete it but it is not in the DB", |
| refEvent.getRefName()); |
| |
| throw new ValidationException( |
| String.format( |
| "Unable to update ref '%s', cannot find it in the shared ref database", |
| refEvent.getRefName()), |
| alreadyInDB); |
| } |
| return Collections.emptyList(); |
| } |
| } |