| /* |
| * 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.pulsar.metadata.coordination.impl; |
| |
| import com.fasterxml.jackson.databind.type.TypeFactory; |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Optional; |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.CompletionException; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.ExecutorService; |
| import java.util.stream.Collectors; |
| import lombok.extern.slf4j.Slf4j; |
| import org.apache.pulsar.common.util.FutureUtil; |
| import org.apache.pulsar.metadata.api.MetadataCache; |
| import org.apache.pulsar.metadata.api.MetadataSerde; |
| import org.apache.pulsar.metadata.api.MetadataStoreException; |
| import org.apache.pulsar.metadata.api.MetadataStoreException.BadVersionException; |
| import org.apache.pulsar.metadata.api.MetadataStoreException.LockBusyException; |
| import org.apache.pulsar.metadata.api.Notification; |
| import org.apache.pulsar.metadata.api.NotificationType; |
| import org.apache.pulsar.metadata.api.coordination.LockManager; |
| import org.apache.pulsar.metadata.api.coordination.ResourceLock; |
| import org.apache.pulsar.metadata.api.extended.MetadataStoreExtended; |
| import org.apache.pulsar.metadata.api.extended.SessionEvent; |
| import org.apache.pulsar.metadata.cache.impl.JSONMetadataSerdeSimpleType; |
| |
| @Slf4j |
| class LockManagerImpl<T> implements LockManager<T> { |
| |
| private final Map<String, ResourceLockImpl<T>> locks = new ConcurrentHashMap<>(); |
| private final MetadataStoreExtended store; |
| private final MetadataCache<T> cache; |
| private final MetadataSerde<T> serde; |
| private final FutureUtil.Sequencer<Void> sequencer; |
| private final ExecutorService executor; |
| |
| private enum State { |
| Ready, Closed |
| } |
| |
| private State state = State.Ready; |
| |
| LockManagerImpl(MetadataStoreExtended store, Class<T> clazz, ExecutorService executor) { |
| this(store, new JSONMetadataSerdeSimpleType<>( |
| TypeFactory.defaultInstance().constructSimpleType(clazz, null)), |
| executor); |
| } |
| |
| LockManagerImpl(MetadataStoreExtended store, MetadataSerde<T> serde, ExecutorService executor) { |
| this.store = store; |
| this.cache = store.getMetadataCache(serde); |
| this.serde = serde; |
| this.executor = executor; |
| this.sequencer = FutureUtil.Sequencer.create(); |
| store.registerSessionListener(this::handleSessionEvent); |
| store.registerListener(this::handleDataNotification); |
| } |
| |
| @Override |
| public CompletableFuture<Optional<T>> readLock(String path) { |
| return cache.get(path); |
| } |
| |
| @Override |
| public CompletableFuture<ResourceLock<T>> acquireLock(String path, T value) { |
| ResourceLockImpl<T> lock = new ResourceLockImpl<>(store, serde, path); |
| |
| CompletableFuture<ResourceLock<T>> result = new CompletableFuture<>(); |
| lock.acquire(value).thenRun(() -> { |
| synchronized (LockManagerImpl.this) { |
| if (state == State.Ready) { |
| locks.put(path, lock); |
| lock.getLockExpiredFuture().thenRun(() -> { |
| log.info("Released resource lock on {}", path); |
| synchronized (LockManagerImpl.this) { |
| locks.remove(path, lock); |
| } |
| }); |
| } else { |
| // LockManager was closed in between. Release the lock asynchronously |
| lock.release(); |
| } |
| } |
| result.complete(lock); |
| }).exceptionally(ex -> { |
| if (ex.getCause() instanceof BadVersionException) { |
| result.completeExceptionally( |
| new LockBusyException("Resource at " + path + " is already locked")); |
| } else { |
| result.completeExceptionally(ex.getCause()); |
| } |
| return null; |
| }); |
| |
| return result; |
| } |
| |
| private void handleSessionEvent(SessionEvent se) { |
| // We want to make sure we're processing one event at a time and that we're done with one event before going |
| // for the next one. |
| sequencer.sequential(() -> FutureUtil.composeAsync(() -> { |
| final List<CompletableFuture<Void>> futures = new ArrayList<>(); |
| if (se == SessionEvent.SessionReestablished) { |
| log.info("Metadata store session has been re-established. Revalidating all the existing locks."); |
| for (ResourceLockImpl<T> lock : locks.values()) { |
| futures.add(lock.silentRevalidateOnce()); |
| } |
| |
| } else if (se == SessionEvent.Reconnected) { |
| log.info("Metadata store connection has been re-established. Revalidating locks that were pending."); |
| for (ResourceLockImpl<T> lock : locks.values()) { |
| futures.add(lock.revalidateIfNeededAfterReconnection()); |
| } |
| } |
| return FutureUtil.waitForAll(futures) |
| .exceptionally(ex -> { |
| log.warn("Failure when processing session event", ex); |
| return null; |
| }); |
| }, executor)); |
| } |
| |
| private void handleDataNotification(Notification n) { |
| if (n.getType() == NotificationType.Deleted) { |
| ResourceLockImpl<T> lock = locks.get(n.getPath()); |
| if (lock != null) { |
| lock.lockWasInvalidated(); |
| } |
| } |
| } |
| |
| @Override |
| public CompletableFuture<List<String>> listLocks(String path) { |
| return cache.getChildren(path); |
| } |
| |
| @Override |
| public void close() throws Exception { |
| try { |
| asyncClose().join(); |
| } catch (CompletionException e) { |
| throw MetadataStoreException.unwrap(e); |
| } |
| } |
| |
| @Override |
| public CompletableFuture<Void> asyncClose() { |
| Map<String, ResourceLock<T>> locks; |
| synchronized (this) { |
| if (state != State.Ready) { |
| return CompletableFuture.completedFuture(null); |
| } |
| |
| locks = new HashMap<>(this.locks); |
| this.state = State.Closed; |
| } |
| |
| return FutureUtil.waitForAll(locks.values().stream() |
| .map(ResourceLock::release) |
| .collect(Collectors.toList())); |
| } |
| } |