| /* |
| * Copyright 2016-present Open Networking Laboratory |
| * |
| * 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 org.onosproject.store.primitives.resources.impl; |
| |
| import static org.onosproject.store.service.MapEvent.Type.INSERT; |
| import static org.onosproject.store.service.MapEvent.Type.REMOVE; |
| import static org.onosproject.store.service.MapEvent.Type.UPDATE; |
| import static org.slf4j.LoggerFactory.getLogger; |
| import io.atomix.copycat.server.session.ServerSession; |
| import io.atomix.copycat.server.Commit; |
| import io.atomix.copycat.server.Snapshottable; |
| import io.atomix.copycat.server.StateMachineExecutor; |
| import io.atomix.copycat.server.session.SessionListener; |
| import io.atomix.copycat.server.storage.snapshot.SnapshotReader; |
| import io.atomix.copycat.server.storage.snapshot.SnapshotWriter; |
| import io.atomix.resource.ResourceStateMachine; |
| |
| import java.util.Collection; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Properties; |
| import java.util.Set; |
| import java.util.concurrent.atomic.AtomicLong; |
| import java.util.stream.Collectors; |
| |
| import org.onlab.util.CountDownCompleter; |
| import org.onlab.util.Match; |
| import org.onosproject.store.primitives.MapUpdate; |
| import org.onosproject.store.primitives.TransactionId; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.Clear; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.ContainsKey; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.ContainsValue; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.EntrySet; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.Get; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.IsEmpty; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.KeySet; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.Listen; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.Size; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.TransactionCommit; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.TransactionPrepare; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.TransactionPrepareAndCommit; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.TransactionRollback; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.Unlisten; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.UpdateAndGet; |
| import org.onosproject.store.primitives.resources.impl.AtomixConsistentMapCommands.Values; |
| import org.onosproject.store.service.MapEvent; |
| import org.onosproject.store.service.MapTransaction; |
| import org.onosproject.store.service.Versioned; |
| import org.slf4j.Logger; |
| |
| import com.google.common.base.Throwables; |
| import com.google.common.collect.Lists; |
| import com.google.common.collect.Maps; |
| import com.google.common.collect.Sets; |
| |
| import static com.google.common.base.Preconditions.checkState; |
| |
| /** |
| * State Machine for {@link AtomixConsistentMap} resource. |
| */ |
| public class AtomixConsistentMapState extends ResourceStateMachine implements SessionListener, Snapshottable { |
| |
| private final Logger log = getLogger(getClass()); |
| private final Map<Long, Commit<? extends AtomixConsistentMapCommands.Listen>> listeners = new HashMap<>(); |
| private final Map<String, MapEntryValue> mapEntries = new HashMap<>(); |
| private final Set<String> preparedKeys = Sets.newHashSet(); |
| private final Map<TransactionId, Commit<? extends TransactionPrepare>> pendingTransactions = Maps.newHashMap(); |
| private AtomicLong versionCounter = new AtomicLong(0); |
| |
| public AtomixConsistentMapState(Properties properties) { |
| super(properties); |
| } |
| |
| @Override |
| public void snapshot(SnapshotWriter writer) { |
| writer.writeLong(versionCounter.get()); |
| } |
| |
| @Override |
| public void install(SnapshotReader reader) { |
| versionCounter = new AtomicLong(reader.readLong()); |
| } |
| |
| @Override |
| protected void configure(StateMachineExecutor executor) { |
| // Listeners |
| executor.register(Listen.class, this::listen); |
| executor.register(Unlisten.class, this::unlisten); |
| // Queries |
| executor.register(ContainsKey.class, this::containsKey); |
| executor.register(ContainsValue.class, this::containsValue); |
| executor.register(EntrySet.class, this::entrySet); |
| executor.register(Get.class, this::get); |
| executor.register(IsEmpty.class, this::isEmpty); |
| executor.register(KeySet.class, this::keySet); |
| executor.register(Size.class, this::size); |
| executor.register(Values.class, this::values); |
| // Commands |
| executor.register(UpdateAndGet.class, this::updateAndGet); |
| executor.register(AtomixConsistentMapCommands.Clear.class, this::clear); |
| executor.register(TransactionPrepare.class, this::prepare); |
| executor.register(TransactionCommit.class, this::commit); |
| executor.register(TransactionRollback.class, this::rollback); |
| executor.register(TransactionPrepareAndCommit.class, this::prepareAndCommit); |
| } |
| |
| @Override |
| public void delete() { |
| // Delete Listeners |
| listeners.values().forEach(Commit::close); |
| listeners.clear(); |
| |
| // Delete Map entries |
| mapEntries.values().forEach(MapEntryValue::discard); |
| mapEntries.clear(); |
| } |
| |
| /** |
| * Handles a contains key commit. |
| * |
| * @param commit containsKey commit |
| * @return {@code true} if map contains key |
| */ |
| protected boolean containsKey(Commit<? extends ContainsKey> commit) { |
| try { |
| return toVersioned(mapEntries.get(commit.operation().key())) != null; |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Handles a contains value commit. |
| * |
| * @param commit containsValue commit |
| * @return {@code true} if map contains value |
| */ |
| protected boolean containsValue(Commit<? extends ContainsValue> commit) { |
| try { |
| Match<byte[]> valueMatch = Match |
| .ifValue(commit.operation().value()); |
| return mapEntries.values().stream() |
| .anyMatch(value -> valueMatch.matches(value.value())); |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Handles a get commit. |
| * |
| * @param commit |
| * get commit |
| * @return value mapped to key |
| */ |
| protected Versioned<byte[]> get(Commit<? extends Get> commit) { |
| try { |
| return toVersioned(mapEntries.get(commit.operation().key())); |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Handles a count commit. |
| * |
| * @param commit size commit |
| * @return number of entries in map |
| */ |
| protected int size(Commit<? extends Size> commit) { |
| try { |
| return mapEntries.size(); |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Handles an is empty commit. |
| * |
| * @param commit isEmpty commit |
| * @return {@code true} if map is empty |
| */ |
| protected boolean isEmpty(Commit<? extends IsEmpty> commit) { |
| try { |
| return mapEntries.isEmpty(); |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Handles a keySet commit. |
| * |
| * @param commit keySet commit |
| * @return set of keys in map |
| */ |
| protected Set<String> keySet(Commit<? extends KeySet> commit) { |
| try { |
| return mapEntries.keySet().stream().collect(Collectors.toSet()); |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Handles a values commit. |
| * |
| * @param commit values commit |
| * @return collection of values in map |
| */ |
| protected Collection<Versioned<byte[]>> values(Commit<? extends Values> commit) { |
| try { |
| return mapEntries.values().stream().map(this::toVersioned).collect(Collectors.toList()); |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Handles a entry set commit. |
| * |
| * @param commit |
| * entrySet commit |
| * @return set of map entries |
| */ |
| protected Set<Map.Entry<String, Versioned<byte[]>>> entrySet(Commit<? extends EntrySet> commit) { |
| try { |
| return mapEntries |
| .entrySet() |
| .stream() |
| .map(e -> Maps.immutableEntry(e.getKey(), |
| toVersioned(e.getValue()))) |
| .collect(Collectors.toSet()); |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Handles a update and get commit. |
| * |
| * @param commit updateAndGet commit |
| * @return update result |
| */ |
| protected MapEntryUpdateResult<String, byte[]> updateAndGet(Commit<? extends UpdateAndGet> commit) { |
| try { |
| MapEntryUpdateResult.Status updateStatus = validate(commit.operation()); |
| String key = commit.operation().key(); |
| MapEntryValue oldCommitValue = mapEntries.get(commit.operation().key()); |
| Versioned<byte[]> oldMapValue = toVersioned(oldCommitValue); |
| |
| if (updateStatus != MapEntryUpdateResult.Status.OK) { |
| commit.close(); |
| return new MapEntryUpdateResult<>(updateStatus, "", key, |
| oldMapValue, oldMapValue); |
| } |
| |
| byte[] newValue = commit.operation().value(); |
| long newVersion = versionCounter.incrementAndGet(); |
| Versioned<byte[]> newMapValue = newValue == null ? null |
| : new Versioned<>(newValue, newVersion); |
| |
| MapEvent.Type updateType = newValue == null ? REMOVE |
| : oldCommitValue == null ? INSERT : UPDATE; |
| if (updateType == REMOVE || updateType == UPDATE) { |
| mapEntries.remove(key); |
| oldCommitValue.discard(); |
| } |
| if (updateType == INSERT || updateType == UPDATE) { |
| mapEntries.put(key, new NonTransactionalCommit(newVersion, commit)); |
| } else { |
| commit.close(); |
| } |
| publish(Lists.newArrayList(new MapEvent<>("", key, newMapValue, oldMapValue))); |
| return new MapEntryUpdateResult<>(updateStatus, "", key, oldMapValue, |
| newMapValue); |
| } catch (Exception e) { |
| log.error("State machine operation failed", e); |
| throw Throwables.propagate(e); |
| } |
| } |
| |
| /** |
| * Handles a clear commit. |
| * |
| * @param commit clear commit |
| * @return clear result |
| */ |
| protected MapEntryUpdateResult.Status clear(Commit<? extends Clear> commit) { |
| try { |
| Iterator<Map.Entry<String, MapEntryValue>> iterator = mapEntries |
| .entrySet().iterator(); |
| while (iterator.hasNext()) { |
| Map.Entry<String, MapEntryValue> entry = iterator.next(); |
| String key = entry.getKey(); |
| MapEntryValue value = entry.getValue(); |
| Versioned<byte[]> removedValue = new Versioned<>(value.value(), |
| value.version()); |
| publish(Lists.newArrayList(new MapEvent<>("", key, null, removedValue))); |
| value.discard(); |
| iterator.remove(); |
| } |
| return MapEntryUpdateResult.Status.OK; |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Handles a listen commit. |
| * |
| * @param commit listen commit |
| */ |
| protected void listen(Commit<? extends Listen> commit) { |
| Long sessionId = commit.session().id(); |
| if (listeners.putIfAbsent(sessionId, commit) != null) { |
| commit.close(); |
| return; |
| } |
| commit.session() |
| .onStateChange( |
| state -> { |
| if (state == ServerSession.State.CLOSED |
| || state == ServerSession.State.EXPIRED) { |
| Commit<? extends Listen> listener = listeners.remove(sessionId); |
| if (listener != null) { |
| listener.close(); |
| } |
| } |
| }); |
| } |
| |
| /** |
| * Handles an unlisten commit. |
| * |
| * @param commit unlisten commit |
| */ |
| protected void unlisten(Commit<? extends Unlisten> commit) { |
| try { |
| Commit<? extends Listen> listener = listeners.remove(commit.session().id()); |
| if (listener != null) { |
| listener.close(); |
| } |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Handles an prepare and commit commit. |
| * |
| * @param commit transaction prepare and commit commit |
| * @return prepare result |
| */ |
| protected PrepareResult prepareAndCommit(Commit<? extends TransactionPrepareAndCommit> commit) { |
| PrepareResult prepareResult = prepare(commit); |
| if (prepareResult == PrepareResult.OK) { |
| commitInternal(commit.operation().transaction().transactionId()); |
| } |
| return prepareResult; |
| } |
| |
| /** |
| * Handles an prepare commit. |
| * |
| * @param commit transaction prepare commit |
| * @return prepare result |
| */ |
| protected PrepareResult prepare(Commit<? extends TransactionPrepare> commit) { |
| boolean ok = false; |
| try { |
| MapTransaction<String, byte[]> transaction = commit.operation().transaction(); |
| for (MapUpdate<String, byte[]> update : transaction.updates()) { |
| String key = update.key(); |
| if (preparedKeys.contains(key)) { |
| return PrepareResult.CONCURRENT_TRANSACTION; |
| } |
| MapEntryValue existingValue = mapEntries.get(key); |
| if (existingValue == null) { |
| if (update.type() != MapUpdate.Type.PUT_IF_ABSENT) { |
| return PrepareResult.OPTIMISTIC_LOCK_FAILURE; |
| } |
| } else { |
| if (existingValue.version() != update.currentVersion()) { |
| return PrepareResult.OPTIMISTIC_LOCK_FAILURE; |
| } |
| } |
| } |
| // No violations detected. Add to pendingTranctions and mark |
| // modified keys as locked for updates. |
| pendingTransactions.put(transaction.transactionId(), commit); |
| transaction.updates().forEach(u -> preparedKeys.add(u.key())); |
| ok = true; |
| return PrepareResult.OK; |
| } catch (Exception e) { |
| log.warn("Failure applying {}", commit, e); |
| throw Throwables.propagate(e); |
| } finally { |
| if (!ok) { |
| commit.close(); |
| } |
| } |
| } |
| |
| /** |
| * Handles an commit commit (ha!). |
| * |
| * @param commit transaction commit commit |
| * @return commit result |
| */ |
| protected CommitResult commit(Commit<? extends TransactionCommit> commit) { |
| TransactionId transactionId = commit.operation().transactionId(); |
| try { |
| return commitInternal(transactionId); |
| } catch (Exception e) { |
| log.warn("Failure applying {}", commit, e); |
| throw Throwables.propagate(e); |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| private CommitResult commitInternal(TransactionId transactionId) { |
| Commit<? extends TransactionPrepare> prepareCommit = pendingTransactions |
| .remove(transactionId); |
| if (prepareCommit == null) { |
| return CommitResult.UNKNOWN_TRANSACTION_ID; |
| } |
| MapTransaction<String, byte[]> transaction = prepareCommit.operation().transaction(); |
| long totalReferencesToCommit = transaction |
| .updates() |
| .stream() |
| .filter(update -> update.type() != MapUpdate.Type.REMOVE_IF_VERSION_MATCH) |
| .count(); |
| CountDownCompleter<Commit<? extends TransactionPrepare>> completer = |
| new CountDownCompleter<>(prepareCommit, totalReferencesToCommit, Commit::close); |
| List<MapEvent<String, byte[]>> eventsToPublish = Lists.newArrayList(); |
| for (MapUpdate<String, byte[]> update : transaction.updates()) { |
| String key = update.key(); |
| checkState(preparedKeys.remove(key), "key is not prepared"); |
| MapEntryValue previousValue = mapEntries.remove(key); |
| MapEntryValue newValue = null; |
| if (update.type() != MapUpdate.Type.REMOVE_IF_VERSION_MATCH) { |
| newValue = new TransactionalCommit(key, versionCounter.incrementAndGet(), completer); |
| } |
| eventsToPublish.add(new MapEvent<>("", key, toVersioned(newValue), toVersioned(previousValue))); |
| if (newValue != null) { |
| mapEntries.put(key, newValue); |
| } |
| if (previousValue != null) { |
| previousValue.discard(); |
| } |
| } |
| publish(eventsToPublish); |
| return CommitResult.OK; |
| } |
| |
| /** |
| * Handles an rollback commit (ha!). |
| * |
| * @param commit transaction rollback commit |
| * @return rollback result |
| */ |
| protected RollbackResult rollback(Commit<? extends TransactionRollback> commit) { |
| TransactionId transactionId = commit.operation().transactionId(); |
| try { |
| Commit<? extends TransactionPrepare> prepareCommit = pendingTransactions.remove(transactionId); |
| if (prepareCommit == null) { |
| return RollbackResult.UNKNOWN_TRANSACTION_ID; |
| } else { |
| prepareCommit.operation() |
| .transaction() |
| .updates() |
| .forEach(u -> preparedKeys.remove(u.key())); |
| prepareCommit.close(); |
| return RollbackResult.OK; |
| } |
| } finally { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Computes the update status that would result if the specified update were to applied to |
| * the state machine. |
| * |
| * @param update update |
| * @return status |
| */ |
| private MapEntryUpdateResult.Status validate(UpdateAndGet update) { |
| MapEntryValue existingValue = mapEntries.get(update.key()); |
| if (existingValue == null && update.value() == null) { |
| return MapEntryUpdateResult.Status.NOOP; |
| } |
| if (preparedKeys.contains(update.key())) { |
| return MapEntryUpdateResult.Status.WRITE_LOCK; |
| } |
| byte[] existingRawValue = existingValue == null ? null : existingValue |
| .value(); |
| Long existingVersion = existingValue == null ? null : existingValue |
| .version(); |
| return update.valueMatch().matches(existingRawValue) |
| && update.versionMatch().matches(existingVersion) ? MapEntryUpdateResult.Status.OK |
| : MapEntryUpdateResult.Status.PRECONDITION_FAILED; |
| } |
| |
| /** |
| * Utility for turning a {@code MapEntryValue} to {@code Versioned}. |
| * @param value map entry value |
| * @return versioned instance |
| */ |
| private Versioned<byte[]> toVersioned(MapEntryValue value) { |
| return value == null ? null : new Versioned<>(value.value(), value.version()); |
| } |
| |
| /** |
| * Publishes events to listeners. |
| * |
| * @param events list of map event to publish |
| */ |
| private void publish(List<MapEvent<String, byte[]>> events) { |
| listeners.values().forEach(commit -> commit.session().publish(AtomixConsistentMap.CHANGE_SUBJECT, events)); |
| } |
| |
| @Override |
| public void register(ServerSession session) { |
| } |
| |
| @Override |
| public void unregister(ServerSession session) { |
| closeListener(session.id()); |
| } |
| |
| @Override |
| public void expire(ServerSession session) { |
| closeListener(session.id()); |
| } |
| |
| @Override |
| public void close(ServerSession session) { |
| closeListener(session.id()); |
| } |
| |
| private void closeListener(Long sessionId) { |
| Commit<? extends Listen> commit = listeners.remove(sessionId); |
| if (commit != null) { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * Interface implemented by map values. |
| */ |
| private interface MapEntryValue { |
| /** |
| * Returns the raw {@code byte[]}. |
| * |
| * @return raw value |
| */ |
| byte[] value(); |
| |
| /** |
| * Returns the version of the value. |
| * |
| * @return version |
| */ |
| long version(); |
| |
| /** |
| * Discards the value by invoke appropriate clean up actions. |
| */ |
| void discard(); |
| } |
| |
| /** |
| * A {@code MapEntryValue} that is derived from a non-transactional update |
| * i.e. via any standard map update operation. |
| */ |
| private class NonTransactionalCommit implements MapEntryValue { |
| private final long version; |
| private final Commit<? extends UpdateAndGet> commit; |
| |
| public NonTransactionalCommit(long version, Commit<? extends UpdateAndGet> commit) { |
| this.version = version; |
| this.commit = commit; |
| } |
| |
| @Override |
| public byte[] value() { |
| return commit.operation().value(); |
| } |
| |
| @Override |
| public long version() { |
| return version; |
| } |
| |
| @Override |
| public void discard() { |
| commit.close(); |
| } |
| } |
| |
| /** |
| * A {@code MapEntryValue} that is derived from updates submitted via a |
| * transaction. |
| */ |
| private class TransactionalCommit implements MapEntryValue { |
| private final String key; |
| private final long version; |
| private final CountDownCompleter<Commit<? extends TransactionPrepare>> completer; |
| |
| public TransactionalCommit( |
| String key, |
| long version, |
| CountDownCompleter<Commit<? extends TransactionPrepare>> commit) { |
| this.key = key; |
| this.version = version; |
| this.completer = commit; |
| } |
| |
| @Override |
| public byte[] value() { |
| MapTransaction<String, byte[]> transaction = completer.object().operation().transaction(); |
| return valueForKey(key, transaction); |
| } |
| |
| @Override |
| public long version() { |
| return version; |
| } |
| |
| @Override |
| public void discard() { |
| completer.countDown(); |
| } |
| |
| private byte[] valueForKey(String key, MapTransaction<String, byte[]> transaction) { |
| MapUpdate<String, byte[]> update = transaction.updates() |
| .stream() |
| .filter(u -> u.key().equals(key)) |
| .findFirst() |
| .orElse(null); |
| return update == null ? null : update.value(); |
| } |
| } |
| } |