opendaylight/md-sal/sal-inmemory-datastore/src/main/java/org/opendaylight/controller/md/sal/dom/store/impl/InMemoryDOMDataStore.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.md.sal.dom.store.impl;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11
  12 import com.google.common.base.Optional;
  13 import com.google.common.base.Preconditions;
  14 import com.google.common.util.concurrent.FutureCallback;
  15 import com.google.common.util.concurrent.Futures;
  16 import com.google.common.util.concurrent.ListenableFuture;
  17 import com.google.common.util.concurrent.ListeningExecutorService;
  18
  19 import java.util.concurrent.Callable;
  20 import java.util.concurrent.ExecutorService;
  21 import java.util.concurrent.TimeUnit;
  22 import java.util.concurrent.atomic.AtomicLong;
  23
  24 import javax.annotation.concurrent.GuardedBy;
  25
  26 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker.DataChangeScope;
  27 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
  28 import org.opendaylight.controller.md.sal.common.api.data.OptimisticLockFailedException;
  29 import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
  30 import org.opendaylight.controller.md.sal.dom.store.impl.SnapshotBackedWriteTransaction.TransactionReadyPrototype;
  31 import org.opendaylight.controller.md.sal.dom.store.impl.tree.ListenerTree;
  32 import org.opendaylight.controller.sal.core.spi.data.DOMStore;
  33 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadTransaction;
  34 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  35 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  36 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain;
  37 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
  38 import org.opendaylight.yangtools.concepts.AbstractListenerRegistration;
  39 import org.opendaylight.yangtools.concepts.Identifiable;
  40 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  41 import org.opendaylight.yangtools.util.ExecutorServiceUtil;
  42 import org.opendaylight.yangtools.util.concurrent.NotificationManager;
  43 import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager;
  44 import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager.Invoker;
  45 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  46 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  47 import org.opendaylight.yangtools.yang.data.api.schema.tree.ConflictingModificationAppliedException;
  48 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree;
  49 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  50 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  51 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  52 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
  53 import org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeFactory;
  54 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  55 import org.opendaylight.yangtools.yang.model.api.SchemaContextListener;
  56 import org.slf4j.Logger;
  57 import org.slf4j.LoggerFactory;
  58
  59 /**
  60  * In-memory DOM Data Store
  61  *
  62  * Implementation of {@link DOMStore} which uses {@link DataTree} and other
  63  * classes such as {@link SnapshotBackedWriteTransaction}.
  64  * {@link SnapshotBackedReadTransaction} and {@link ResolveDataChangeEventsTask}
  65  * to implement {@link DOMStore} contract.
  66  *
  67  */
  68 public class InMemoryDOMDataStore implements DOMStore, Identifiable<String>, SchemaContextListener,
  69         TransactionReadyPrototype,AutoCloseable {
  70     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDOMDataStore.class);
  71     private static final ListenableFuture<Void> SUCCESSFUL_FUTURE = Futures.immediateFuture(null);
  72
  73     private static final Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> DCL_NOTIFICATION_MGR_INVOKER =
  74             new Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent>() {
  75                 @Override
  76                 public void invokeListener(final DataChangeListenerRegistration<?> listener,
  77                                            final DOMImmutableDataChangeEvent notification ) {
  78                     final AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> inst = listener.getInstance();
  79                     if (inst != null) {
  80                         inst.onDataChanged(notification);
  81                     }
  82                 }
  83             };
  84
  85     private final DataTree dataTree = InMemoryDataTreeFactory.getInstance().create();
  86     private final ListenerTree listenerTree = ListenerTree.create();
  87     private final AtomicLong txCounter = new AtomicLong(0);
  88     private final ListeningExecutorService listeningExecutor;
  89
  90     private final NotificationManager<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> dataChangeListenerNotificationManager;
  91     private final ExecutorService dataChangeListenerExecutor;
  92
  93     private final String name;
  94
  95     public InMemoryDOMDataStore(final String name, final ListeningExecutorService listeningExecutor,
  96             final ExecutorService dataChangeListenerExecutor) {
  97         this(name, listeningExecutor, dataChangeListenerExecutor,
  98                 InMemoryDOMDataStoreConfigProperties.DEFAULT_MAX_DATA_CHANGE_LISTENER_QUEUE_SIZE);
  99     }
 100
 101     public InMemoryDOMDataStore(final String name, final ListeningExecutorService listeningExecutor,
 102             final ExecutorService dataChangeListenerExecutor, final int maxDataChangeListenerQueueSize) {
 103         this.name = Preconditions.checkNotNull(name);
 104         this.listeningExecutor = Preconditions.checkNotNull(listeningExecutor);
 105         this.dataChangeListenerExecutor = Preconditions.checkNotNull(dataChangeListenerExecutor);
 106
 107         dataChangeListenerNotificationManager =
 108                 new QueuedNotificationManager<>(this.dataChangeListenerExecutor,
 109                         DCL_NOTIFICATION_MGR_INVOKER, maxDataChangeListenerQueueSize,
 110                         "DataChangeListenerQueueMgr");
 111     }
 112
 113     @Override
 114     public final String getIdentifier() {
 115         return name;
 116     }
 117
 118     @Override
 119     public DOMStoreReadTransaction newReadOnlyTransaction() {
 120         return new SnapshotBackedReadTransaction(nextIdentifier(), dataTree.takeSnapshot());
 121     }
 122
 123     @Override
 124     public DOMStoreReadWriteTransaction newReadWriteTransaction() {
 125         return new SnapshotBackedReadWriteTransaction(nextIdentifier(), dataTree.takeSnapshot(), this);
 126     }
 127
 128     @Override
 129     public DOMStoreWriteTransaction newWriteOnlyTransaction() {
 130         return new SnapshotBackedWriteTransaction(nextIdentifier(), dataTree.takeSnapshot(), this);
 131     }
 132
 133     @Override
 134     public DOMStoreTransactionChain createTransactionChain() {
 135         return new DOMStoreTransactionChainImpl();
 136     }
 137
 138     @Override
 139     public synchronized void onGlobalContextUpdated(final SchemaContext ctx) {
 140         dataTree.setSchemaContext(ctx);
 141     }
 142
 143     @Override
 144     public void close() {
 145         ExecutorServiceUtil.tryGracefulShutdown(listeningExecutor, 30, TimeUnit.SECONDS);
 146         ExecutorServiceUtil.tryGracefulShutdown(dataChangeListenerExecutor, 30, TimeUnit.SECONDS);
 147     }
 148     @Override
 149     public <L extends AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> ListenerRegistration<L> registerChangeListener(
 150             final YangInstanceIdentifier path, final L listener, final DataChangeScope scope) {
 151
 152         /*
 153          * Make sure commit is not occurring right now. Listener has to be
 154          * registered and its state capture enqueued at a consistent point.
 155          *
 156          * FIXME: improve this to read-write lock, such that multiple listener
 157          * registrations can occur simultaneously
 158          */
 159         final DataChangeListenerRegistration<L> reg;
 160         synchronized (this) {
 161             LOG.debug("{}: Registering data change listener {} for {}", name, listener, path);
 162
 163             reg = listenerTree.registerDataChangeListener(path, listener, scope);
 164
 165             Optional<NormalizedNode<?, ?>> currentState = dataTree.takeSnapshot().readNode(path);
 166             if (currentState.isPresent()) {
 167                 final NormalizedNode<?, ?> data = currentState.get();
 168
 169                 final DOMImmutableDataChangeEvent event = DOMImmutableDataChangeEvent.builder(DataChangeScope.BASE) //
 170                         .setAfter(data) //
 171                         .addCreated(path, data) //
 172                         .build();
 173
 174                 dataChangeListenerNotificationManager.submitNotification(reg, event);
 175             }
 176         }
 177
 178         return new AbstractListenerRegistration<L>(listener) {
 179             @Override
 180             protected void removeRegistration() {
 181                 synchronized (InMemoryDOMDataStore.this) {
 182                     reg.close();
 183                 }
 184             }
 185         };
 186     }
 187
 188     @Override
 189     public DOMStoreThreePhaseCommitCohort ready(final SnapshotBackedWriteTransaction writeTx) {
 190         LOG.debug("Tx: {} is submitted. Modifications: {}", writeTx.getIdentifier(), writeTx.getMutatedView());
 191         return new ThreePhaseCommitImpl(writeTx);
 192     }
 193
 194     private Object nextIdentifier() {
 195         return name + "-" + txCounter.getAndIncrement();
 196     }
 197
 198     private class DOMStoreTransactionChainImpl implements DOMStoreTransactionChain, TransactionReadyPrototype {
 199
 200         @GuardedBy("this")
 201         private SnapshotBackedWriteTransaction latestOutstandingTx;
 202
 203         private boolean chainFailed = false;
 204
 205         private void checkFailed() {
 206             Preconditions.checkState(!chainFailed, "Transaction chain is failed.");
 207         }
 208
 209         @Override
 210         public synchronized DOMStoreReadTransaction newReadOnlyTransaction() {
 211             final DataTreeSnapshot snapshot;
 212             checkFailed();
 213             if (latestOutstandingTx != null) {
 214                 checkState(latestOutstandingTx.isReady(), "Previous transaction in chain must be ready.");
 215                 snapshot = latestOutstandingTx.getMutatedView();
 216             } else {
 217                 snapshot = dataTree.takeSnapshot();
 218             }
 219             return new SnapshotBackedReadTransaction(nextIdentifier(), snapshot);
 220         }
 221
 222         @Override
 223         public synchronized DOMStoreReadWriteTransaction newReadWriteTransaction() {
 224             final DataTreeSnapshot snapshot;
 225             checkFailed();
 226             if (latestOutstandingTx != null) {
 227                 checkState(latestOutstandingTx.isReady(), "Previous transaction in chain must be ready.");
 228                 snapshot = latestOutstandingTx.getMutatedView();
 229             } else {
 230                 snapshot = dataTree.takeSnapshot();
 231             }
 232             final SnapshotBackedReadWriteTransaction ret = new SnapshotBackedReadWriteTransaction(nextIdentifier(),
 233                     snapshot, this);
 234             latestOutstandingTx = ret;
 235             return ret;
 236         }
 237
 238         @Override
 239         public synchronized DOMStoreWriteTransaction newWriteOnlyTransaction() {
 240             final DataTreeSnapshot snapshot;
 241             checkFailed();
 242             if (latestOutstandingTx != null) {
 243                 checkState(latestOutstandingTx.isReady(), "Previous transaction in chain must be ready.");
 244                 snapshot = latestOutstandingTx.getMutatedView();
 245             } else {
 246                 snapshot = dataTree.takeSnapshot();
 247             }
 248             final SnapshotBackedWriteTransaction ret = new SnapshotBackedWriteTransaction(nextIdentifier(), snapshot,
 249                     this);
 250             latestOutstandingTx = ret;
 251             return ret;
 252         }
 253
 254         @Override
 255         public DOMStoreThreePhaseCommitCohort ready(final SnapshotBackedWriteTransaction tx) {
 256             DOMStoreThreePhaseCommitCohort storeCohort = InMemoryDOMDataStore.this.ready(tx);
 257             return new ChainedTransactionCommitImpl(tx, storeCohort, this);
 258         }
 259
 260         @Override
 261         public void close() {
 262
 263             // FIXME: this call doesn't look right here - listeningExecutor is shared and owned
 264             // by the outer class.
 265             //listeningExecutor.shutdownNow();
 266         }
 267
 268         protected synchronized void onTransactionFailed(final SnapshotBackedWriteTransaction transaction,
 269                 final Throwable t) {
 270             chainFailed = true;
 271
 272         }
 273
 274         public synchronized void onTransactionCommited(final SnapshotBackedWriteTransaction transaction) {
 275             // If committed transaction is latestOutstandingTx we clear
 276             // latestOutstandingTx
 277             // field in order to base new transactions on Datastore Data Tree
 278             // directly.
 279             if (transaction.equals(latestOutstandingTx)) {
 280                 latestOutstandingTx = null;
 281             }
 282         }
 283
 284     }
 285
 286     private static class ChainedTransactionCommitImpl implements DOMStoreThreePhaseCommitCohort {
 287
 288         private final SnapshotBackedWriteTransaction transaction;
 289         private final DOMStoreThreePhaseCommitCohort delegate;
 290
 291         private final DOMStoreTransactionChainImpl txChain;
 292
 293         protected ChainedTransactionCommitImpl(final SnapshotBackedWriteTransaction transaction,
 294                 final DOMStoreThreePhaseCommitCohort delegate, final DOMStoreTransactionChainImpl txChain) {
 295             super();
 296             this.transaction = transaction;
 297             this.delegate = delegate;
 298             this.txChain = txChain;
 299         }
 300
 301         @Override
 302         public ListenableFuture<Boolean> canCommit() {
 303             return delegate.canCommit();
 304         }
 305
 306         @Override
 307         public ListenableFuture<Void> preCommit() {
 308             return delegate.preCommit();
 309         }
 310
 311         @Override
 312         public ListenableFuture<Void> abort() {
 313             return delegate.abort();
 314         }
 315
 316         @Override
 317         public ListenableFuture<Void> commit() {
 318             ListenableFuture<Void> commitFuture = delegate.commit();
 319             Futures.addCallback(commitFuture, new FutureCallback<Void>() {
 320                 @Override
 321                 public void onFailure(final Throwable t) {
 322                     txChain.onTransactionFailed(transaction, t);
 323                 }
 324
 325                 @Override
 326                 public void onSuccess(final Void result) {
 327                     txChain.onTransactionCommited(transaction);
 328                 }
 329
 330             });
 331             return commitFuture;
 332         }
 333
 334     }
 335
 336     private class ThreePhaseCommitImpl implements DOMStoreThreePhaseCommitCohort {
 337
 338         private final SnapshotBackedWriteTransaction transaction;
 339         private final DataTreeModification modification;
 340
 341         private ResolveDataChangeEventsTask listenerResolver;
 342         private DataTreeCandidate candidate;
 343
 344         public ThreePhaseCommitImpl(final SnapshotBackedWriteTransaction writeTransaction) {
 345             this.transaction = writeTransaction;
 346             this.modification = transaction.getMutatedView();
 347         }
 348
 349         @Override
 350         public ListenableFuture<Boolean> canCommit() {
 351             return listeningExecutor.submit(new Callable<Boolean>() {
 352                 @Override
 353                 public Boolean call() throws TransactionCommitFailedException {
 354                     try {
 355                         dataTree.validate(modification);
 356                         LOG.debug("Store Transaction: {} can be committed", transaction.getIdentifier());
 357                         return true;
 358                     } catch (ConflictingModificationAppliedException e) {
 359                         LOG.warn("Store Tx: {} Conflicting modification for {}.", transaction.getIdentifier(),
 360                                 e.getPath());
 361                         throw new OptimisticLockFailedException("Optimistic lock failed.",e);
 362                     } catch (DataValidationFailedException e) {
 363                         LOG.warn("Store Tx: {} Data Precondition failed for {}.", transaction.getIdentifier(),
 364                                 e.getPath(), e);
 365                         throw new TransactionCommitFailedException("Data did not pass validation.",e);
 366                     }
 367                 }
 368             });
 369         }
 370
 371         @Override
 372         public ListenableFuture<Void> preCommit() {
 373             return listeningExecutor.submit(new Callable<Void>() {
 374                 @Override
 375                 public Void call() {
 376                     candidate = dataTree.prepare(modification);
 377                     listenerResolver = ResolveDataChangeEventsTask.create(candidate, listenerTree);
 378                     return null;
 379                 }
 380             });
 381         }
 382
 383         @Override
 384         public ListenableFuture<Void> abort() {
 385             candidate = null;
 386             return SUCCESSFUL_FUTURE;
 387         }
 388
 389         @Override
 390         public ListenableFuture<Void> commit() {
 391             checkState(candidate != null, "Proposed subtree must be computed");
 392
 393             /*
 394              * The commit has to occur atomically with regard to listener
 395              * registrations.
 396              */
 397             synchronized (this) {
 398                 dataTree.commit(candidate);
 399                 listenerResolver.resolve(dataChangeListenerNotificationManager);
 400             }
 401
 402             return SUCCESSFUL_FUTURE;
 403         }
 404     }
 405 }