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.Futures;
  14 import com.google.common.util.concurrent.ListenableFuture;
  15 import java.util.concurrent.ExecutorService;
  16 import java.util.concurrent.TimeUnit;
  17 import java.util.concurrent.atomic.AtomicLong;
  18 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker.DataChangeScope;
  19 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
  20 import org.opendaylight.controller.md.sal.common.api.data.OptimisticLockFailedException;
  21 import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
  22 import org.opendaylight.controller.md.sal.dom.api.DOMDataTreeChangeListener;
  23 import org.opendaylight.controller.md.sal.dom.store.impl.SnapshotBackedWriteTransaction.TransactionReadyPrototype;
  24 import org.opendaylight.controller.md.sal.dom.store.impl.tree.ListenerTree;
  25 import org.opendaylight.controller.sal.core.spi.data.DOMStore;
  26 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadTransaction;
  27 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  28 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  29 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain;
  30 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTreeChangePublisher;
  31 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
  32 import org.opendaylight.yangtools.concepts.AbstractListenerRegistration;
  33 import org.opendaylight.yangtools.concepts.Identifiable;
  34 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  35 import org.opendaylight.yangtools.util.ExecutorServiceUtil;
  36 import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager;
  37 import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager.Invoker;
  38 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  39 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  40 import org.opendaylight.yangtools.yang.data.api.schema.tree.ConflictingModificationAppliedException;
  41 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree;
  42 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  43 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  44 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  45 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
  46 import org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeFactory;
  47 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  48 import org.opendaylight.yangtools.yang.model.api.SchemaContextListener;
  49 import org.slf4j.Logger;
  50 import org.slf4j.LoggerFactory;
  51
  52 /**
  53  * In-memory DOM Data Store
  54  *
  55  * Implementation of {@link DOMStore} which uses {@link DataTree} and other
  56  * classes such as {@link SnapshotBackedWriteTransaction}.
  57  * {@link SnapshotBackedReadTransaction} and {@link ResolveDataChangeEventsTask}
  58  * to implement {@link DOMStore} contract.
  59  *
  60  */
  61 public class InMemoryDOMDataStore extends TransactionReadyPrototype implements DOMStore, Identifiable<String>, SchemaContextListener, AutoCloseable, DOMStoreTreeChangePublisher {
  62     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDOMDataStore.class);
  63     private static final ListenableFuture<Void> SUCCESSFUL_FUTURE = Futures.immediateFuture(null);
  64     private static final ListenableFuture<Boolean> CAN_COMMIT_FUTURE = Futures.immediateFuture(Boolean.TRUE);
  65
  66     private static final Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> DCL_NOTIFICATION_MGR_INVOKER =
  67             new Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent>() {
  68                 @Override
  69                 public void invokeListener(final DataChangeListenerRegistration<?> listener,
  70                                            final DOMImmutableDataChangeEvent notification ) {
  71                     final AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> inst = listener.getInstance();
  72                     if (inst != null) {
  73                         inst.onDataChanged(notification);
  74                     }
  75                 }
  76             };
  77
  78     private final DataTree dataTree = InMemoryDataTreeFactory.getInstance().create();
  79     private final ListenerTree listenerTree = ListenerTree.create();
  80     private final AtomicLong txCounter = new AtomicLong(0);
  81
  82     private final QueuedNotificationManager<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> dataChangeListenerNotificationManager;
  83     private final InMemoryDOMStoreTreeChangePublisher changePublisher;
  84     private final ExecutorService dataChangeListenerExecutor;
  85     private final boolean debugTransactions;
  86     private final String name;
  87
  88     private volatile AutoCloseable closeable;
  89
  90     public InMemoryDOMDataStore(final String name, final ExecutorService dataChangeListenerExecutor) {
  91         this(name, dataChangeListenerExecutor, InMemoryDOMDataStoreConfigProperties.DEFAULT_MAX_DATA_CHANGE_LISTENER_QUEUE_SIZE, false);
  92     }
  93
  94     public InMemoryDOMDataStore(final String name, final ExecutorService dataChangeListenerExecutor,
  95             final int maxDataChangeListenerQueueSize, final boolean debugTransactions) {
  96         this.name = Preconditions.checkNotNull(name);
  97         this.dataChangeListenerExecutor = Preconditions.checkNotNull(dataChangeListenerExecutor);
  98         this.debugTransactions = debugTransactions;
  99
 100         dataChangeListenerNotificationManager =
 101                 new QueuedNotificationManager<>(this.dataChangeListenerExecutor,
 102                         DCL_NOTIFICATION_MGR_INVOKER, maxDataChangeListenerQueueSize,
 103                         "DataChangeListenerQueueMgr");
 104         changePublisher = new InMemoryDOMStoreTreeChangePublisher(this.dataChangeListenerExecutor, maxDataChangeListenerQueueSize);
 105     }
 106
 107     public void setCloseable(final AutoCloseable closeable) {
 108         this.closeable = closeable;
 109     }
 110
 111     public QueuedNotificationManager<?, ?> getDataChangeListenerNotificationManager() {
 112         return dataChangeListenerNotificationManager;
 113     }
 114
 115     @Override
 116     public final String getIdentifier() {
 117         return name;
 118     }
 119
 120     @Override
 121     public DOMStoreReadTransaction newReadOnlyTransaction() {
 122         return new SnapshotBackedReadTransaction(nextIdentifier(), debugTransactions, dataTree.takeSnapshot());
 123     }
 124
 125     @Override
 126     public DOMStoreReadWriteTransaction newReadWriteTransaction() {
 127         return new SnapshotBackedReadWriteTransaction(nextIdentifier(), debugTransactions, dataTree.takeSnapshot(), this);
 128     }
 129
 130     @Override
 131     public DOMStoreWriteTransaction newWriteOnlyTransaction() {
 132         return new SnapshotBackedWriteTransaction(nextIdentifier(), debugTransactions, dataTree.takeSnapshot(), this);
 133     }
 134
 135     @Override
 136     public DOMStoreTransactionChain createTransactionChain() {
 137         return new DOMStoreTransactionChainImpl(this);
 138     }
 139
 140     @Override
 141     public synchronized void onGlobalContextUpdated(final SchemaContext ctx) {
 142         dataTree.setSchemaContext(ctx);
 143     }
 144
 145     @Override
 146     public void close() {
 147         ExecutorServiceUtil.tryGracefulShutdown(dataChangeListenerExecutor, 30, TimeUnit.SECONDS);
 148
 149         if(closeable != null) {
 150             try {
 151                 closeable.close();
 152             } catch(Exception e) {
 153                 LOG.debug("Error closing instance", e);
 154             }
 155         }
 156     }
 157
 158     public final boolean getDebugTransactions() {
 159         return debugTransactions;
 160     }
 161
 162     final DataTreeSnapshot takeSnapshot() {
 163         return dataTree.takeSnapshot();
 164     }
 165
 166     @Override
 167     public <L extends AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> ListenerRegistration<L> registerChangeListener(
 168             final YangInstanceIdentifier path, final L listener, final DataChangeScope scope) {
 169
 170         /*
 171          * Make sure commit is not occurring right now. Listener has to be
 172          * registered and its state capture enqueued at a consistent point.
 173          *
 174          * FIXME: improve this to read-write lock, such that multiple listener
 175          * registrations can occur simultaneously
 176          */
 177         final DataChangeListenerRegistration<L> reg;
 178         synchronized (this) {
 179             LOG.debug("{}: Registering data change listener {} for {}", name, listener, path);
 180
 181             reg = listenerTree.registerDataChangeListener(path, listener, scope);
 182
 183             Optional<NormalizedNode<?, ?>> currentState = dataTree.takeSnapshot().readNode(path);
 184             if (currentState.isPresent()) {
 185                 final NormalizedNode<?, ?> data = currentState.get();
 186
 187                 final DOMImmutableDataChangeEvent event = DOMImmutableDataChangeEvent.builder(DataChangeScope.BASE) //
 188                         .setAfter(data) //
 189                         .addCreated(path, data) //
 190                         .build();
 191
 192                 dataChangeListenerNotificationManager.submitNotification(reg, event);
 193             }
 194         }
 195
 196         return new AbstractListenerRegistration<L>(listener) {
 197             @Override
 198             protected void removeRegistration() {
 199                 synchronized (InMemoryDOMDataStore.this) {
 200                     reg.close();
 201                 }
 202             }
 203         };
 204     }
 205
 206     @Override
 207     public <L extends DOMDataTreeChangeListener> ListenerRegistration<L> registerTreeChangeListener(final YangInstanceIdentifier treeId, final L listener) {
 208         return changePublisher.registerTreeChangeListener(treeId, listener);
 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     Object nextIdentifier() {
 223         return name + "-" + txCounter.getAndIncrement();
 224     }
 225
 226     private final class ThreePhaseCommitImpl implements DOMStoreThreePhaseCommitCohort {
 227         private final SnapshotBackedWriteTransaction transaction;
 228         private final DataTreeModification modification;
 229
 230         private ResolveDataChangeEventsTask listenerResolver;
 231         private DataTreeCandidate candidate;
 232
 233         public ThreePhaseCommitImpl(final SnapshotBackedWriteTransaction writeTransaction, final DataTreeModification modification) {
 234             this.transaction = writeTransaction;
 235             this.modification = modification;
 236         }
 237
 238         @Override
 239         public ListenableFuture<Boolean> canCommit() {
 240             try {
 241                 dataTree.validate(modification);
 242                 LOG.debug("Store Transaction: {} can be committed", transaction.getIdentifier());
 243                 return CAN_COMMIT_FUTURE;
 244             } catch (ConflictingModificationAppliedException e) {
 245                 LOG.warn("Store Tx: {} Conflicting modification for {}.", transaction.getIdentifier(),
 246                         e.getPath());
 247                 transaction.warnDebugContext(LOG);
 248                 return Futures.immediateFailedFuture(new OptimisticLockFailedException("Optimistic lock failed.", e));
 249             } catch (DataValidationFailedException e) {
 250                 LOG.warn("Store Tx: {} Data Precondition failed for {}.", transaction.getIdentifier(),
 251                         e.getPath(), e);
 252                 transaction.warnDebugContext(LOG);
 253
 254                 // For debugging purposes, allow dumping of the modification. Coupled with the above
 255                 // precondition log, it should allow us to understand what went on.
 256                 LOG.trace("Store Tx: {} modifications: {} tree: {}", modification, dataTree);
 257
 258                 return Futures.immediateFailedFuture(new TransactionCommitFailedException("Data did not pass validation.", e));
 259             } catch (Exception e) {
 260                 LOG.warn("Unexpected failure in validation phase", e);
 261                 return Futures.immediateFailedFuture(e);
 262             }
 263         }
 264
 265         @Override
 266         public ListenableFuture<Void> preCommit() {
 267             try {
 268                 candidate = dataTree.prepare(modification);
 269                 listenerResolver = ResolveDataChangeEventsTask.create(candidate, listenerTree);
 270                 return SUCCESSFUL_FUTURE;
 271             } catch (Exception e) {
 272                 LOG.warn("Unexpected failure in pre-commit phase", e);
 273                 return Futures.immediateFailedFuture(e);
 274             }
 275         }
 276
 277         @Override
 278         public ListenableFuture<Void> abort() {
 279             candidate = null;
 280             return SUCCESSFUL_FUTURE;
 281         }
 282
 283         @Override
 284         public ListenableFuture<Void> commit() {
 285             checkState(candidate != null, "Proposed subtree must be computed");
 286
 287             /*
 288              * The commit has to occur atomically with regard to listener
 289              * registrations.
 290              */
 291             synchronized (InMemoryDOMDataStore.this) {
 292                 dataTree.commit(candidate);
 293                 changePublisher.publishChange(candidate);
 294                 listenerResolver.resolve(dataChangeListenerNotificationManager);
 295             }
 296
 297             return SUCCESSFUL_FUTURE;
 298         }
 299     }
 300 }