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
  72     private static final Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> DCL_NOTIFICATION_MGR_INVOKER =
  73             new Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent>() {
  74                 @Override
  75                 public void invokeListener(final DataChangeListenerRegistration<?> listener,
  76                                            final DOMImmutableDataChangeEvent notification ) {
  77                     final AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> inst = listener.getInstance();
  78                     if (inst != null) {
  79                         inst.onDataChanged(notification);
  80                     }
  81                 }
  82             };
  83
  84     private final DataTree dataTree = InMemoryDataTreeFactory.getInstance().create();
  85     private final ListenerTree listenerTree = ListenerTree.create();
  86     private final AtomicLong txCounter = new AtomicLong(0);
  87     private final ListeningExecutorService listeningExecutor;
  88
  89     private final NotificationManager<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> dataChangeListenerNotificationManager;
  90     private final ExecutorService dataChangeListenerExecutor;
  91
  92     private final String name;
  93
  94     public InMemoryDOMDataStore(final String name, final ListeningExecutorService listeningExecutor,
  95             final ExecutorService dataChangeListenerExecutor) {
  96         this(name, listeningExecutor, dataChangeListenerExecutor,
  97                 InMemoryDOMDataStoreConfigProperties.DEFAULT_MAX_DATA_CHANGE_LISTENER_QUEUE_SIZE);
  98     }
  99
 100     public InMemoryDOMDataStore(final String name, final ListeningExecutorService listeningExecutor,
 101             final ExecutorService dataChangeListenerExecutor, final int maxDataChangeListenerQueueSize) {
 102         this.name = Preconditions.checkNotNull(name);
 103         this.listeningExecutor = Preconditions.checkNotNull(listeningExecutor);
 104         this.dataChangeListenerExecutor = Preconditions.checkNotNull(dataChangeListenerExecutor);
 105
 106         dataChangeListenerNotificationManager =
 107                 new QueuedNotificationManager<>(this.dataChangeListenerExecutor,
 108                         DCL_NOTIFICATION_MGR_INVOKER, maxDataChangeListenerQueueSize,
 109                         "DataChangeListenerQueueMgr");
 110     }
 111
 112     @Override
 113     public final String getIdentifier() {
 114         return name;
 115     }
 116
 117     @Override
 118     public DOMStoreReadTransaction newReadOnlyTransaction() {
 119         return new SnapshotBackedReadTransaction(nextIdentifier(), dataTree.takeSnapshot());
 120     }
 121
 122     @Override
 123     public DOMStoreReadWriteTransaction newReadWriteTransaction() {
 124         return new SnapshotBackedReadWriteTransaction(nextIdentifier(), dataTree.takeSnapshot(), this);
 125     }
 126
 127     @Override
 128     public DOMStoreWriteTransaction newWriteOnlyTransaction() {
 129         return new SnapshotBackedWriteTransaction(nextIdentifier(), dataTree.takeSnapshot(), this);
 130     }
 131
 132     @Override
 133     public DOMStoreTransactionChain createTransactionChain() {
 134         return new DOMStoreTransactionChainImpl();
 135     }
 136
 137     @Override
 138     public synchronized void onGlobalContextUpdated(final SchemaContext ctx) {
 139         dataTree.setSchemaContext(ctx);
 140     }
 141
 142     @Override
 143     public void close() {
 144         ExecutorServiceUtil.tryGracefulShutdown(listeningExecutor, 30, TimeUnit.SECONDS);
 145         ExecutorServiceUtil.tryGracefulShutdown(dataChangeListenerExecutor, 30, TimeUnit.SECONDS);
 146     }
 147     @Override
 148     public <L extends AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> ListenerRegistration<L> registerChangeListener(
 149             final YangInstanceIdentifier path, final L listener, final DataChangeScope scope) {
 150
 151         /*
 152          * Make sure commit is not occurring right now. Listener has to be
 153          * registered and its state capture enqueued at a consistent point.
 154          *
 155          * FIXME: improve this to read-write lock, such that multiple listener
 156          * registrations can occur simultaneously
 157          */
 158         final DataChangeListenerRegistration<L> reg;
 159         synchronized (this) {
 160             LOG.debug("{}: Registering data change listener {} for {}", name, listener, path);
 161
 162             reg = listenerTree.registerDataChangeListener(path, listener, scope);
 163
 164             Optional<NormalizedNode<?, ?>> currentState = dataTree.takeSnapshot().readNode(path);
 165             if (currentState.isPresent()) {
 166                 final NormalizedNode<?, ?> data = currentState.get();
 167
 168                 final DOMImmutableDataChangeEvent event = DOMImmutableDataChangeEvent.builder(DataChangeScope.BASE) //
 169                         .setAfter(data) //
 170                         .addCreated(path, data) //
 171                         .build();
 172
 173                 dataChangeListenerNotificationManager.submitNotification(reg, event);
 174             }
 175         }
 176
 177         return new AbstractListenerRegistration<L>(listener) {
 178             @Override
 179             protected void removeRegistration() {
 180                 synchronized (InMemoryDOMDataStore.this) {
 181                     reg.close();
 182                 }
 183             }
 184         };
 185     }
 186
 187     @Override
 188     public DOMStoreThreePhaseCommitCohort ready(final SnapshotBackedWriteTransaction writeTx) {
 189         LOG.debug("Tx: {} is submitted. Modifications: {}", writeTx.getIdentifier(), writeTx.getMutatedView());
 190         return new ThreePhaseCommitImpl(writeTx);
 191     }
 192
 193     private Object nextIdentifier() {
 194         return name + "-" + txCounter.getAndIncrement();
 195     }
 196
 197     private class DOMStoreTransactionChainImpl implements DOMStoreTransactionChain, TransactionReadyPrototype {
 198
 199         @GuardedBy("this")
 200         private SnapshotBackedWriteTransaction latestOutstandingTx;
 201
 202         private boolean chainFailed = false;
 203
 204         private void checkFailed() {
 205             Preconditions.checkState(!chainFailed, "Transaction chain is failed.");
 206         }
 207
 208         @Override
 209         public synchronized DOMStoreReadTransaction newReadOnlyTransaction() {
 210             final DataTreeSnapshot snapshot;
 211             checkFailed();
 212             if (latestOutstandingTx != null) {
 213                 checkState(latestOutstandingTx.isReady(), "Previous transaction in chain must be ready.");
 214                 snapshot = latestOutstandingTx.getMutatedView();
 215             } else {
 216                 snapshot = dataTree.takeSnapshot();
 217             }
 218             return new SnapshotBackedReadTransaction(nextIdentifier(), snapshot);
 219         }
 220
 221         @Override
 222         public synchronized DOMStoreReadWriteTransaction newReadWriteTransaction() {
 223             final DataTreeSnapshot snapshot;
 224             checkFailed();
 225             if (latestOutstandingTx != null) {
 226                 checkState(latestOutstandingTx.isReady(), "Previous transaction in chain must be ready.");
 227                 snapshot = latestOutstandingTx.getMutatedView();
 228             } else {
 229                 snapshot = dataTree.takeSnapshot();
 230             }
 231             final SnapshotBackedReadWriteTransaction ret = new SnapshotBackedReadWriteTransaction(nextIdentifier(),
 232                     snapshot, this);
 233             latestOutstandingTx = ret;
 234             return ret;
 235         }
 236
 237         @Override
 238         public synchronized DOMStoreWriteTransaction newWriteOnlyTransaction() {
 239             final DataTreeSnapshot snapshot;
 240             checkFailed();
 241             if (latestOutstandingTx != null) {
 242                 checkState(latestOutstandingTx.isReady(), "Previous transaction in chain must be ready.");
 243                 snapshot = latestOutstandingTx.getMutatedView();
 244             } else {
 245                 snapshot = dataTree.takeSnapshot();
 246             }
 247             final SnapshotBackedWriteTransaction ret = new SnapshotBackedWriteTransaction(nextIdentifier(), snapshot,
 248                     this);
 249             latestOutstandingTx = ret;
 250             return ret;
 251         }
 252
 253         @Override
 254         public DOMStoreThreePhaseCommitCohort ready(final SnapshotBackedWriteTransaction tx) {
 255             DOMStoreThreePhaseCommitCohort storeCohort = InMemoryDOMDataStore.this.ready(tx);
 256             return new ChainedTransactionCommitImpl(tx, storeCohort, this);
 257         }
 258
 259         @Override
 260         public void close() {
 261
 262             // FIXME: this call doesn't look right here - listeningExecutor is shared and owned
 263             // by the outer class.
 264             //listeningExecutor.shutdownNow();
 265         }
 266
 267         protected synchronized void onTransactionFailed(final SnapshotBackedWriteTransaction transaction,
 268                 final Throwable t) {
 269             chainFailed = true;
 270
 271         }
 272
 273         public synchronized void onTransactionCommited(final SnapshotBackedWriteTransaction transaction) {
 274             // If committed transaction is latestOutstandingTx we clear
 275             // latestOutstandingTx
 276             // field in order to base new transactions on Datastore Data Tree
 277             // directly.
 278             if (transaction.equals(latestOutstandingTx)) {
 279                 latestOutstandingTx = null;
 280             }
 281         }
 282
 283     }
 284
 285     private static class ChainedTransactionCommitImpl implements DOMStoreThreePhaseCommitCohort {
 286
 287         private final SnapshotBackedWriteTransaction transaction;
 288         private final DOMStoreThreePhaseCommitCohort delegate;
 289
 290         private final DOMStoreTransactionChainImpl txChain;
 291
 292         protected ChainedTransactionCommitImpl(final SnapshotBackedWriteTransaction transaction,
 293                 final DOMStoreThreePhaseCommitCohort delegate, final DOMStoreTransactionChainImpl txChain) {
 294             super();
 295             this.transaction = transaction;
 296             this.delegate = delegate;
 297             this.txChain = txChain;
 298         }
 299
 300         @Override
 301         public ListenableFuture<Boolean> canCommit() {
 302             return delegate.canCommit();
 303         }
 304
 305         @Override
 306         public ListenableFuture<Void> preCommit() {
 307             return delegate.preCommit();
 308         }
 309
 310         @Override
 311         public ListenableFuture<Void> abort() {
 312             return delegate.abort();
 313         }
 314
 315         @Override
 316         public ListenableFuture<Void> commit() {
 317             ListenableFuture<Void> commitFuture = delegate.commit();
 318             Futures.addCallback(commitFuture, new FutureCallback<Void>() {
 319                 @Override
 320                 public void onFailure(final Throwable t) {
 321                     txChain.onTransactionFailed(transaction, t);
 322                 }
 323
 324                 @Override
 325                 public void onSuccess(final Void result) {
 326                     txChain.onTransactionCommited(transaction);
 327                 }
 328
 329             });
 330             return commitFuture;
 331         }
 332
 333     }
 334
 335     private class ThreePhaseCommitImpl implements DOMStoreThreePhaseCommitCohort {
 336
 337         private final SnapshotBackedWriteTransaction transaction;
 338         private final DataTreeModification modification;
 339
 340         private ResolveDataChangeEventsTask listenerResolver;
 341         private DataTreeCandidate candidate;
 342
 343         public ThreePhaseCommitImpl(final SnapshotBackedWriteTransaction writeTransaction) {
 344             this.transaction = writeTransaction;
 345             this.modification = transaction.getMutatedView();
 346         }
 347
 348         @Override
 349         public ListenableFuture<Boolean> canCommit() {
 350             return listeningExecutor.submit(new Callable<Boolean>() {
 351                 @Override
 352                 public Boolean call() throws TransactionCommitFailedException {
 353                     try {
 354                         dataTree.validate(modification);
 355                         LOG.debug("Store Transaction: {} can be committed", transaction.getIdentifier());
 356                         return true;
 357                     } catch (ConflictingModificationAppliedException e) {
 358                         LOG.warn("Store Tx: {} Conflicting modification for {}.", transaction.getIdentifier(),
 359                                 e.getPath());
 360                         throw new OptimisticLockFailedException("Optimistic lock failed.",e);
 361                     } catch (DataValidationFailedException e) {
 362                         LOG.warn("Store Tx: {} Data Precondition failed for {}.", transaction.getIdentifier(),
 363                                 e.getPath(), e);
 364                         throw new TransactionCommitFailedException("Data did not pass validation.",e);
 365                     }
 366                 }
 367             });
 368         }
 369
 370         @Override
 371         public ListenableFuture<Void> preCommit() {
 372             return listeningExecutor.submit(new Callable<Void>() {
 373                 @Override
 374                 public Void call() {
 375                     candidate = dataTree.prepare(modification);
 376                     listenerResolver = ResolveDataChangeEventsTask.create(candidate, listenerTree);
 377                     return null;
 378                 }
 379             });
 380         }
 381
 382         @Override
 383         public ListenableFuture<Void> abort() {
 384             candidate = null;
 385             return Futures.immediateFuture(null);
 386         }
 387
 388         @Override
 389         public ListenableFuture<Void> commit() {
 390             checkState(candidate != null, "Proposed subtree must be computed");
 391
 392             /*
 393              * The commit has to occur atomically with regard to listener
 394              * registrations.
 395              */
 396             synchronized (this) {
 397                 dataTree.commit(candidate);
 398                 listenerResolver.resolve(dataChangeListenerNotificationManager);
 399             }
 400
 401             return Futures.immediateFuture(null);
 402         }
 403     }
 404 }