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