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 import com.google.common.base.Optional;
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.util.concurrent.FutureCallback;
  14 import com.google.common.util.concurrent.Futures;
  15 import com.google.common.util.concurrent.ListenableFuture;
  16 import com.google.common.util.concurrent.ListeningExecutorService;
  17 import com.google.common.util.concurrent.MoreExecutors;
  18 import java.util.concurrent.Callable;
  19 import java.util.concurrent.ExecutorService;
  20 import java.util.concurrent.TimeUnit;
  21 import java.util.concurrent.atomic.AtomicLong;
  22 import javax.annotation.concurrent.GuardedBy;
  23 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker.DataChangeScope;
  24 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
  25 import org.opendaylight.controller.md.sal.common.api.data.OptimisticLockFailedException;
  26 import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
  27 import org.opendaylight.controller.md.sal.dom.store.impl.SnapshotBackedWriteTransaction.TransactionReadyPrototype;
  28 import org.opendaylight.controller.md.sal.dom.store.impl.tree.ListenerTree;
  29 import org.opendaylight.controller.sal.core.spi.data.DOMStore;
  30 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadTransaction;
  31 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  32 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  33 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain;
  34 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
  35 import org.opendaylight.yangtools.concepts.AbstractListenerRegistration;
  36 import org.opendaylight.yangtools.concepts.Identifiable;
  37 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  38 import org.opendaylight.yangtools.util.ExecutorServiceUtil;
  39 import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager;
  40 import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager.Invoker;
  41 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  42 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  43 import org.opendaylight.yangtools.yang.data.api.schema.tree.ConflictingModificationAppliedException;
  44 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree;
  45 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  46 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  47 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  48 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
  49 import org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeFactory;
  50 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  51 import org.opendaylight.yangtools.yang.model.api.SchemaContextListener;
  52 import org.slf4j.Logger;
  53 import org.slf4j.LoggerFactory;
  54
  55 /**
  56  * In-memory DOM Data Store
  57  *
  58  * Implementation of {@link DOMStore} which uses {@link DataTree} and other
  59  * classes such as {@link SnapshotBackedWriteTransaction}.
  60  * {@link SnapshotBackedReadTransaction} and {@link ResolveDataChangeEventsTask}
  61  * to implement {@link DOMStore} contract.
  62  *
  63  */
  64 public class InMemoryDOMDataStore extends TransactionReadyPrototype implements DOMStore, Identifiable<String>, SchemaContextListener, AutoCloseable {
  65     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDOMDataStore.class);
  66     private static final ListenableFuture<Void> SUCCESSFUL_FUTURE = Futures.immediateFuture(null);
  67
  68     private static final Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> DCL_NOTIFICATION_MGR_INVOKER =
  69             new Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent>() {
  70                 @Override
  71                 public void invokeListener(final DataChangeListenerRegistration<?> listener,
  72                                            final DOMImmutableDataChangeEvent notification ) {
  73                     final AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> inst = listener.getInstance();
  74                     if (inst != null) {
  75                         inst.onDataChanged(notification);
  76                     }
  77                 }
  78             };
  79
  80     private final DataTree dataTree = InMemoryDataTreeFactory.getInstance().create();
  81     private final ListenerTree listenerTree = ListenerTree.create();
  82     private final AtomicLong txCounter = new AtomicLong(0);
  83     private final ListeningExecutorService listeningExecutor;
  84
  85     private final QueuedNotificationManager<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> dataChangeListenerNotificationManager;
  86     private final ExecutorService dataChangeListenerExecutor;
  87
  88     private final ExecutorService domStoreExecutor;
  89     private final boolean debugTransactions;
  90     private final String name;
  91
  92     private volatile AutoCloseable closeable;
  93
  94     public InMemoryDOMDataStore(final String name, final ExecutorService domStoreExecutor,
  95             final ExecutorService dataChangeListenerExecutor) {
  96         this(name, domStoreExecutor, dataChangeListenerExecutor,
  97              InMemoryDOMDataStoreConfigProperties.DEFAULT_MAX_DATA_CHANGE_LISTENER_QUEUE_SIZE, false);
  98     }
  99
 100     public InMemoryDOMDataStore(final String name, final ExecutorService domStoreExecutor,
 101             final ExecutorService dataChangeListenerExecutor, final int maxDataChangeListenerQueueSize,
 102             final boolean debugTransactions) {
 103         this.name = Preconditions.checkNotNull(name);
 104         this.domStoreExecutor = Preconditions.checkNotNull(domStoreExecutor);
 105         this.listeningExecutor = MoreExecutors.listeningDecorator(this.domStoreExecutor);
 106         this.dataChangeListenerExecutor = Preconditions.checkNotNull(dataChangeListenerExecutor);
 107         this.debugTransactions = debugTransactions;
 108
 109         dataChangeListenerNotificationManager =
 110                 new QueuedNotificationManager<>(this.dataChangeListenerExecutor,
 111                         DCL_NOTIFICATION_MGR_INVOKER, maxDataChangeListenerQueueSize,
 112                         "DataChangeListenerQueueMgr");
 113     }
 114
 115     public void setCloseable(final AutoCloseable closeable) {
 116         this.closeable = closeable;
 117     }
 118
 119     public QueuedNotificationManager<?, ?> getDataChangeListenerNotificationManager() {
 120         return dataChangeListenerNotificationManager;
 121     }
 122
 123     public ExecutorService getDomStoreExecutor() {
 124         return domStoreExecutor;
 125     }
 126
 127     @Override
 128     public final String getIdentifier() {
 129         return name;
 130     }
 131
 132     @Override
 133     public DOMStoreReadTransaction newReadOnlyTransaction() {
 134         return new SnapshotBackedReadTransaction(nextIdentifier(), debugTransactions, dataTree.takeSnapshot());
 135     }
 136
 137     @Override
 138     public DOMStoreReadWriteTransaction newReadWriteTransaction() {
 139         return new SnapshotBackedReadWriteTransaction(nextIdentifier(), debugTransactions, dataTree.takeSnapshot(), this);
 140     }
 141
 142     @Override
 143     public DOMStoreWriteTransaction newWriteOnlyTransaction() {
 144         return new SnapshotBackedWriteTransaction(nextIdentifier(), debugTransactions, dataTree.takeSnapshot(), this);
 145     }
 146
 147     @Override
 148     public DOMStoreTransactionChain createTransactionChain() {
 149         return new DOMStoreTransactionChainImpl();
 150     }
 151
 152     @Override
 153     public synchronized void onGlobalContextUpdated(final SchemaContext ctx) {
 154         dataTree.setSchemaContext(ctx);
 155     }
 156
 157     @Override
 158     public void close() {
 159         ExecutorServiceUtil.tryGracefulShutdown(listeningExecutor, 30, TimeUnit.SECONDS);
 160         ExecutorServiceUtil.tryGracefulShutdown(dataChangeListenerExecutor, 30, TimeUnit.SECONDS);
 161
 162         if(closeable != null) {
 163             try {
 164                 closeable.close();
 165             } catch(Exception e) {
 166                 LOG.debug("Error closing instance", e);
 167             }
 168         }
 169     }
 170
 171     boolean getDebugTransactions() {
 172         return debugTransactions;
 173     }
 174
 175     @Override
 176     public <L extends AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> ListenerRegistration<L> registerChangeListener(
 177             final YangInstanceIdentifier path, final L listener, final DataChangeScope scope) {
 178
 179         /*
 180          * Make sure commit is not occurring right now. Listener has to be
 181          * registered and its state capture enqueued at a consistent point.
 182          *
 183          * FIXME: improve this to read-write lock, such that multiple listener
 184          * registrations can occur simultaneously
 185          */
 186         final DataChangeListenerRegistration<L> reg;
 187         synchronized (this) {
 188             LOG.debug("{}: Registering data change listener {} for {}", name, listener, path);
 189
 190             reg = listenerTree.registerDataChangeListener(path, listener, scope);
 191
 192             Optional<NormalizedNode<?, ?>> currentState = dataTree.takeSnapshot().readNode(path);
 193             if (currentState.isPresent()) {
 194                 final NormalizedNode<?, ?> data = currentState.get();
 195
 196                 final DOMImmutableDataChangeEvent event = DOMImmutableDataChangeEvent.builder(DataChangeScope.BASE) //
 197                         .setAfter(data) //
 198                         .addCreated(path, data) //
 199                         .build();
 200
 201                 dataChangeListenerNotificationManager.submitNotification(reg, event);
 202             }
 203         }
 204
 205         return new AbstractListenerRegistration<L>(listener) {
 206             @Override
 207             protected void removeRegistration() {
 208                 synchronized (InMemoryDOMDataStore.this) {
 209                     reg.close();
 210                 }
 211             }
 212         };
 213     }
 214
 215     @Override
 216     protected void transactionAborted(final SnapshotBackedWriteTransaction tx) {
 217         LOG.debug("Tx: {} is closed.", tx.getIdentifier());
 218     }
 219
 220     @Override
 221     protected DOMStoreThreePhaseCommitCohort transactionReady(final SnapshotBackedWriteTransaction tx, final DataTreeModification tree) {
 222         LOG.debug("Tx: {} is submitted. Modifications: {}", tx.getIdentifier(), tree);
 223         return new ThreePhaseCommitImpl(tx, tree);
 224     }
 225
 226     private Object nextIdentifier() {
 227         return name + "-" + txCounter.getAndIncrement();
 228     }
 229
 230     private class DOMStoreTransactionChainImpl extends TransactionReadyPrototype implements DOMStoreTransactionChain {
 231         @GuardedBy("this")
 232         private SnapshotBackedWriteTransaction allocatedTransaction;
 233         @GuardedBy("this")
 234         private DataTreeSnapshot readySnapshot;
 235         @GuardedBy("this")
 236         private boolean chainFailed = false;
 237
 238         @GuardedBy("this")
 239         private void checkFailed() {
 240             Preconditions.checkState(!chainFailed, "Transaction chain is failed.");
 241         }
 242
 243         @GuardedBy("this")
 244         private DataTreeSnapshot getSnapshot() {
 245             checkFailed();
 246
 247             if (allocatedTransaction != null) {
 248                 Preconditions.checkState(readySnapshot != null, "Previous transaction %s is not ready yet", allocatedTransaction.getIdentifier());
 249                 return readySnapshot;
 250             } else {
 251                 return dataTree.takeSnapshot();
 252             }
 253         }
 254
 255         @GuardedBy("this")
 256         private <T extends SnapshotBackedWriteTransaction> T recordTransaction(final T transaction) {
 257             allocatedTransaction = transaction;
 258             readySnapshot = null;
 259             return transaction;
 260         }
 261
 262         @Override
 263         public synchronized DOMStoreReadTransaction newReadOnlyTransaction() {
 264             final DataTreeSnapshot snapshot = getSnapshot();
 265             return new SnapshotBackedReadTransaction(nextIdentifier(), getDebugTransactions(), snapshot);
 266         }
 267
 268         @Override
 269         public synchronized DOMStoreReadWriteTransaction newReadWriteTransaction() {
 270             final DataTreeSnapshot snapshot = getSnapshot();
 271             return recordTransaction(new SnapshotBackedReadWriteTransaction(nextIdentifier(),
 272                     getDebugTransactions(), snapshot, this));
 273         }
 274
 275         @Override
 276         public synchronized DOMStoreWriteTransaction newWriteOnlyTransaction() {
 277             final DataTreeSnapshot snapshot = getSnapshot();
 278             return recordTransaction(new SnapshotBackedWriteTransaction(nextIdentifier(),
 279                     getDebugTransactions(), snapshot, this));
 280         }
 281
 282         @Override
 283         protected synchronized void transactionAborted(final SnapshotBackedWriteTransaction tx) {
 284             if (tx.equals(allocatedTransaction)) {
 285                 Preconditions.checkState(readySnapshot == null, "Unexpected abort of transaction %s with ready snapshot %s", tx, readySnapshot);
 286                 allocatedTransaction = null;
 287             }
 288         }
 289
 290         @Override
 291         protected synchronized DOMStoreThreePhaseCommitCohort transactionReady(final SnapshotBackedWriteTransaction tx, final DataTreeModification tree) {
 292             Preconditions.checkState(tx.equals(allocatedTransaction), "Mis-ordered ready transaction %s last allocated was %s", tx, allocatedTransaction);
 293             if (readySnapshot != null) {
 294                 // The snapshot should have been cleared
 295                 LOG.warn("Uncleared snapshot {} encountered, overwritten with transaction {} snapshot {}", readySnapshot, tx, tree);
 296             }
 297
 298             final DOMStoreThreePhaseCommitCohort cohort = InMemoryDOMDataStore.this.transactionReady(tx, tree);
 299             readySnapshot = tree;
 300             return new ChainedTransactionCommitImpl(tx, cohort, this);
 301         }
 302
 303         @Override
 304         public void close() {
 305             // FIXME: this call doesn't look right here - listeningExecutor is shared and owned
 306             // by the outer class.
 307             //listeningExecutor.shutdownNow();
 308         }
 309
 310         protected synchronized void onTransactionFailed(final SnapshotBackedWriteTransaction transaction,
 311                 final Throwable t) {
 312             chainFailed = true;
 313         }
 314
 315         public synchronized void onTransactionCommited(final SnapshotBackedWriteTransaction transaction) {
 316             // If the committed transaction was the one we allocated last,
 317             // we clear it and the ready snapshot, so the next transaction
 318             // allocated refers to the data tree directly.
 319             if (transaction.equals(allocatedTransaction)) {
 320                 if (readySnapshot == null) {
 321                     LOG.warn("Transaction {} committed while no ready snapshot present", transaction);
 322                 }
 323
 324                 allocatedTransaction = null;
 325                 readySnapshot = null;
 326             }
 327         }
 328     }
 329
 330     private static class ChainedTransactionCommitImpl implements DOMStoreThreePhaseCommitCohort {
 331         private final SnapshotBackedWriteTransaction transaction;
 332         private final DOMStoreThreePhaseCommitCohort delegate;
 333         private final DOMStoreTransactionChainImpl txChain;
 334
 335         protected ChainedTransactionCommitImpl(final SnapshotBackedWriteTransaction transaction,
 336                 final DOMStoreThreePhaseCommitCohort delegate, final DOMStoreTransactionChainImpl txChain) {
 337             this.transaction = transaction;
 338             this.delegate = delegate;
 339             this.txChain = txChain;
 340         }
 341
 342         @Override
 343         public ListenableFuture<Boolean> canCommit() {
 344             return delegate.canCommit();
 345         }
 346
 347         @Override
 348         public ListenableFuture<Void> preCommit() {
 349             return delegate.preCommit();
 350         }
 351
 352         @Override
 353         public ListenableFuture<Void> abort() {
 354             return delegate.abort();
 355         }
 356
 357         @Override
 358         public ListenableFuture<Void> commit() {
 359             ListenableFuture<Void> commitFuture = delegate.commit();
 360             Futures.addCallback(commitFuture, new FutureCallback<Void>() {
 361                 @Override
 362                 public void onFailure(final Throwable t) {
 363                     txChain.onTransactionFailed(transaction, t);
 364                 }
 365
 366                 @Override
 367                 public void onSuccess(final Void result) {
 368                     txChain.onTransactionCommited(transaction);
 369                 }
 370             });
 371             return commitFuture;
 372         }
 373     }
 374
 375     private class ThreePhaseCommitImpl implements DOMStoreThreePhaseCommitCohort {
 376         private final SnapshotBackedWriteTransaction transaction;
 377         private final DataTreeModification modification;
 378
 379         private ResolveDataChangeEventsTask listenerResolver;
 380         private DataTreeCandidate candidate;
 381
 382         public ThreePhaseCommitImpl(final SnapshotBackedWriteTransaction writeTransaction, final DataTreeModification modification) {
 383             this.transaction = writeTransaction;
 384             this.modification = modification;
 385         }
 386
 387         @Override
 388         public ListenableFuture<Boolean> canCommit() {
 389             return listeningExecutor.submit(new Callable<Boolean>() {
 390                 @Override
 391                 public Boolean call() throws TransactionCommitFailedException {
 392                     try {
 393                         dataTree.validate(modification);
 394                         LOG.debug("Store Transaction: {} can be committed", transaction.getIdentifier());
 395                         return true;
 396                     } catch (ConflictingModificationAppliedException e) {
 397                         LOG.warn("Store Tx: {} Conflicting modification for {}.", transaction.getIdentifier(),
 398                                 e.getPath());
 399                         transaction.warnDebugContext(LOG);
 400                         throw new OptimisticLockFailedException("Optimistic lock failed.",e);
 401                     } catch (DataValidationFailedException e) {
 402                         LOG.warn("Store Tx: {} Data Precondition failed for {}.", transaction.getIdentifier(),
 403                                 e.getPath(), e);
 404                         transaction.warnDebugContext(LOG);
 405                         throw new TransactionCommitFailedException("Data did not pass validation.",e);
 406                     }
 407                 }
 408             });
 409         }
 410
 411         @Override
 412         public ListenableFuture<Void> preCommit() {
 413             return listeningExecutor.submit(new Callable<Void>() {
 414                 @Override
 415                 public Void call() {
 416                     candidate = dataTree.prepare(modification);
 417                     listenerResolver = ResolveDataChangeEventsTask.create(candidate, listenerTree);
 418                     return null;
 419                 }
 420             });
 421         }
 422
 423         @Override
 424         public ListenableFuture<Void> abort() {
 425             candidate = null;
 426             return SUCCESSFUL_FUTURE;
 427         }
 428
 429         @Override
 430         public ListenableFuture<Void> commit() {
 431             checkState(candidate != null, "Proposed subtree must be computed");
 432
 433             /*
 434              * The commit has to occur atomically with regard to listener
 435              * registrations.
 436              */
 437             synchronized (InMemoryDOMDataStore.this) {
 438                 dataTree.commit(candidate);
 439                 listenerResolver.resolve(dataChangeListenerNotificationManager);
 440             }
 441
 442             return SUCCESSFUL_FUTURE;
 443         }
 444     }
 445 }