opendaylight/md-sal/sal-dom-broker/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.checkNotNull;
  11 import static com.google.common.base.Preconditions.checkState;
  12 import static org.opendaylight.controller.md.sal.dom.store.impl.StoreUtils.increase;
  13
  14 import java.util.concurrent.Callable;
  15 import java.util.concurrent.atomic.AtomicLong;
  16
  17 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker.DataChangeScope;
  18 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
  19 import org.opendaylight.controller.md.sal.dom.store.impl.tree.ListenerRegistrationNode;
  20 import org.opendaylight.controller.md.sal.dom.store.impl.tree.NodeModification;
  21 import org.opendaylight.controller.md.sal.dom.store.impl.tree.StoreMetadataNode;
  22 import org.opendaylight.controller.md.sal.dom.store.impl.tree.TreeNodeUtils;
  23 import org.opendaylight.controller.sal.core.spi.data.DOMStore;
  24 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadTransaction;
  25 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  26 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  27 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
  28 import org.opendaylight.yangtools.concepts.Identifiable;
  29 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  30 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
  31 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.PathArgument;
  32 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  33 import org.opendaylight.yangtools.yang.data.impl.schema.NormalizedNodeUtils;
  34 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  35 import org.opendaylight.yangtools.yang.model.api.SchemaContextListener;
  36 import org.slf4j.Logger;
  37 import org.slf4j.LoggerFactory;
  38
  39 import com.google.common.base.Optional;
  40 import com.google.common.primitives.UnsignedLong;
  41 import com.google.common.util.concurrent.Futures;
  42 import com.google.common.util.concurrent.ListenableFuture;
  43 import com.google.common.util.concurrent.ListeningExecutorService;
  44
  45 public class InMemoryDOMDataStore implements DOMStore, Identifiable<String>, SchemaContextListener {
  46
  47     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDOMDataStore.class);
  48     private static final InstanceIdentifier PUBLIC_ROOT_PATH = InstanceIdentifier.builder().build();
  49
  50
  51     private final ListeningExecutorService executor;
  52     private final String name;
  53     private final AtomicLong txCounter = new AtomicLong(0);
  54
  55     private DataAndMetadataSnapshot snapshot;
  56     private ModificationApplyOperation operationTree;
  57     private final ListenerRegistrationNode listenerTree;
  58
  59
  60
  61     private SchemaContext schemaContext;
  62
  63     public InMemoryDOMDataStore(final String name, final ListeningExecutorService executor) {
  64         this.executor = executor;
  65         this.name = name;
  66         this.operationTree = new AllwaysFailOperation();
  67         this.snapshot = DataAndMetadataSnapshot.createEmpty();
  68         this.listenerTree = ListenerRegistrationNode.createRoot();
  69     }
  70
  71     @Override
  72     public String getIdentifier() {
  73         return name;
  74     }
  75
  76     @Override
  77     public DOMStoreReadTransaction newReadOnlyTransaction() {
  78         return new SnapshotBackedReadTransaction(nextIdentifier(), snapshot);
  79     }
  80
  81     @Override
  82     public DOMStoreReadWriteTransaction newReadWriteTransaction() {
  83         return new SnapshotBackedReadWriteTransaction(nextIdentifier(), snapshot, this, operationTree);
  84     }
  85
  86     @Override
  87     public DOMStoreWriteTransaction newWriteOnlyTransaction() {
  88         return new SnaphostBackedWriteTransaction(nextIdentifier(), snapshot, this, operationTree);
  89     }
  90
  91     @Override
  92     public synchronized void onGlobalContextUpdated(final SchemaContext ctx) {
  93         operationTree = SchemaAwareApplyOperationRoot.from(ctx);
  94         schemaContext = ctx;
  95     }
  96
  97     @Override
  98     public <L extends AsyncDataChangeListener<InstanceIdentifier, NormalizedNode<?, ?>>> ListenerRegistration<L> registerChangeListener(
  99             final InstanceIdentifier path, final L listener, final DataChangeScope scope) {
 100
 101         Optional<ListenerRegistrationNode> listenerNode = TreeNodeUtils.findNode(listenerTree, path);
 102         checkState(listenerNode.isPresent());
 103         synchronized (listener) {
 104             notifyInitialState(path, listener);
 105         }
 106         return listenerNode.get().registerDataChangeListener(listener, scope);
 107     }
 108
 109     private void notifyInitialState(final InstanceIdentifier path,
 110             final AsyncDataChangeListener<InstanceIdentifier, NormalizedNode<?, ?>> listener) {
 111         Optional<StoreMetadataNode> currentState = snapshot.read(path);
 112         try {
 113             if (currentState.isPresent()) {
 114                 NormalizedNode<?, ?> data = currentState.get().getData();
 115                 listener.onDataChanged(DOMImmutableDataChangeEvent.builder() //
 116                         .setAfter(data) //
 117                         .addCreated(path, data) //
 118                         .build() //
 119                 );
 120             }
 121         } catch (Exception e) {
 122             LOG.error("Unhandled exception encountered when invoking listener {}", listener, e);
 123         }
 124
 125     }
 126
 127     private synchronized DOMStoreThreePhaseCommitCohort submit(
 128             final SnaphostBackedWriteTransaction snaphostBackedWriteTransaction) {
 129         return new ThreePhaseCommitImpl(snaphostBackedWriteTransaction);
 130     }
 131
 132     private Object nextIdentifier() {
 133         return name + "-" + txCounter.getAndIncrement();
 134     }
 135
 136     private synchronized void commit(final DataAndMetadataSnapshot currentSnapshot,
 137             final StoreMetadataNode newDataTree, final Iterable<ChangeListenerNotifyTask> listenerTasks) {
 138         LOG.debug("Updating Store snaphot version: {} with version:{}",currentSnapshot.getMetadataTree().getSubtreeVersion(),newDataTree.getSubtreeVersion());
 139         checkState(snapshot == currentSnapshot, "Store snapshot and transaction snapshot differs");
 140         snapshot = DataAndMetadataSnapshot.builder() //
 141                 .setMetadataTree(newDataTree) //
 142                 .setSchemaContext(schemaContext) //
 143                 .build();
 144
 145         for(ChangeListenerNotifyTask task : listenerTasks) {
 146             executor.submit(task);
 147         }
 148
 149     }
 150
 151     private static class SnapshotBackedReadTransaction implements DOMStoreReadTransaction {
 152
 153         private DataAndMetadataSnapshot stableSnapshot;
 154         private final Object identifier;
 155
 156         public SnapshotBackedReadTransaction(final Object identifier, final DataAndMetadataSnapshot snapshot) {
 157             this.identifier = identifier;
 158             this.stableSnapshot = snapshot;
 159         }
 160
 161         @Override
 162         public Object getIdentifier() {
 163             return identifier;
 164         }
 165
 166         @Override
 167         public void close() {
 168             stableSnapshot = null;
 169         }
 170
 171         @Override
 172         public ListenableFuture<Optional<NormalizedNode<?, ?>>> read(final InstanceIdentifier path) {
 173             checkNotNull(path, "Path must not be null.");
 174             checkState(stableSnapshot != null, "Transaction is closed");
 175             return Futures.immediateFuture(NormalizedNodeUtils.findNode(stableSnapshot.getDataTree(), path));
 176         }
 177
 178         @Override
 179         public String toString() {
 180             return "SnapshotBackedReadTransaction [id =" + identifier + "]";
 181         }
 182
 183     }
 184
 185     private static class SnaphostBackedWriteTransaction implements DOMStoreWriteTransaction {
 186
 187         private MutableDataTree mutableTree;
 188         private final Object identifier;
 189         private InMemoryDOMDataStore store;
 190
 191         private boolean ready = false;
 192
 193         public SnaphostBackedWriteTransaction(final Object identifier, final DataAndMetadataSnapshot snapshot,
 194                 final InMemoryDOMDataStore store, final ModificationApplyOperation applyOper) {
 195             this.identifier = identifier;
 196             mutableTree = MutableDataTree.from(snapshot, applyOper);
 197             this.store = store;
 198         }
 199
 200         @Override
 201         public Object getIdentifier() {
 202             return identifier;
 203         }
 204
 205         @Override
 206         public void close() {
 207             this.mutableTree = null;
 208             this.store = null;
 209         }
 210
 211         @Override
 212         public void write(final InstanceIdentifier path, final NormalizedNode<?, ?> data) {
 213             checkNotReady();
 214             mutableTree.write(path, data);
 215         }
 216
 217         @Override
 218         public void delete(final InstanceIdentifier path) {
 219             checkNotReady();
 220             mutableTree.delete(path);
 221         }
 222
 223         protected boolean isReady() {
 224             return ready;
 225         }
 226
 227         protected void checkNotReady() {
 228             checkState(!ready, "Transaction is ready. No further modifications allowed.");
 229         }
 230
 231         @Override
 232         public synchronized DOMStoreThreePhaseCommitCohort ready() {
 233             ready = true;
 234             LOG.debug("Store transaction: {} : Ready", getIdentifier());
 235             mutableTree.seal();
 236             return store.submit(this);
 237         }
 238
 239         protected MutableDataTree getMutatedView() {
 240             return mutableTree;
 241         }
 242
 243         @Override
 244         public String toString() {
 245             return "SnaphostBackedWriteTransaction [id=" + getIdentifier() + ", ready=" + isReady() + "]";
 246         }
 247
 248     }
 249
 250     private static class SnapshotBackedReadWriteTransaction extends SnaphostBackedWriteTransaction implements
 251             DOMStoreReadWriteTransaction {
 252
 253         protected SnapshotBackedReadWriteTransaction(final Object identifier, final DataAndMetadataSnapshot snapshot,
 254                 final InMemoryDOMDataStore store, final ModificationApplyOperation applyOper) {
 255             super(identifier, snapshot, store, applyOper);
 256         }
 257
 258         @Override
 259         public ListenableFuture<Optional<NormalizedNode<?, ?>>> read(final InstanceIdentifier path) {
 260             return Futures.immediateFuture(getMutatedView().read(path));
 261         }
 262
 263         @Override
 264         public String toString() {
 265             return "SnapshotBackedReadWriteTransaction [id=" + getIdentifier() + ", ready=" + isReady() + "]";
 266         }
 267
 268     }
 269
 270     private class ThreePhaseCommitImpl implements DOMStoreThreePhaseCommitCohort {
 271
 272         private final SnaphostBackedWriteTransaction transaction;
 273         private final NodeModification modification;
 274
 275         private DataAndMetadataSnapshot storeSnapshot;
 276         private Optional<StoreMetadataNode> proposedSubtree;
 277         private Iterable<ChangeListenerNotifyTask> listenerTasks;
 278
 279         public ThreePhaseCommitImpl(final SnaphostBackedWriteTransaction writeTransaction) {
 280             this.transaction = writeTransaction;
 281             this.modification = transaction.getMutatedView().getRootModification();
 282         }
 283
 284         @Override
 285         public ListenableFuture<Boolean> canCommit() {
 286             final DataAndMetadataSnapshot snapshotCapture = snapshot;
 287             final ModificationApplyOperation snapshotOperation = operationTree;
 288
 289             return executor.submit(new Callable<Boolean>() {
 290
 291                 @Override
 292                 public Boolean call() throws Exception {
 293                     boolean applicable = snapshotOperation.isApplicable(modification,
 294                             Optional.of(snapshotCapture.getMetadataTree()));
 295                     LOG.debug("Store Transcation: {} : canCommit : {}", transaction.getIdentifier(), applicable);
 296                     return applicable;
 297                 }
 298             });
 299         }
 300
 301         @Override
 302         public ListenableFuture<Void> preCommit() {
 303             storeSnapshot = snapshot;
 304             return executor.submit(new Callable<Void>() {
 305
 306
 307
 308                 @Override
 309                 public Void call() throws Exception {
 310                     StoreMetadataNode metadataTree = storeSnapshot.getMetadataTree();
 311
 312                     proposedSubtree = operationTree.apply(modification, Optional.of(metadataTree),
 313                             increase(metadataTree.getSubtreeVersion()));
 314
 315
 316                     listenerTasks = DataChangeEventResolver.create() //
 317                             .setRootPath(PUBLIC_ROOT_PATH) //
 318                             .setBeforeRoot(Optional.of(metadataTree)) //
 319                             .setAfterRoot(proposedSubtree) //
 320                             .setModificationRoot(modification) //
 321                             .setListenerRoot(listenerTree) //
 322                             .resolve();
 323
 324                     return null;
 325                 }
 326             });
 327         }
 328
 329         @Override
 330         public ListenableFuture<Void> abort() {
 331             storeSnapshot = null;
 332             proposedSubtree = null;
 333             return Futures.<Void> immediateFuture(null);
 334         }
 335
 336         @Override
 337         public ListenableFuture<Void> commit() {
 338             checkState(proposedSubtree != null);
 339             checkState(storeSnapshot != null);
 340             // return ImmediateFuture<>;
 341             InMemoryDOMDataStore.this.commit(storeSnapshot, proposedSubtree.get(),listenerTasks);
 342             return Futures.<Void> immediateFuture(null);
 343         }
 344
 345     }
 346
 347     private class AllwaysFailOperation implements ModificationApplyOperation {
 348
 349         @Override
 350         public Optional<StoreMetadataNode> apply(final NodeModification modification,
 351                 final Optional<StoreMetadataNode> storeMeta, final UnsignedLong subtreeVersion) {
 352             throw new IllegalStateException("Schema Context is not available.");
 353         }
 354
 355         @Override
 356         public boolean isApplicable(final NodeModification modification, final Optional<StoreMetadataNode> storeMetadata) {
 357             throw new IllegalStateException("Schema Context is not available.");
 358         }
 359
 360         @Override
 361         public Optional<ModificationApplyOperation> getChild(final PathArgument child) {
 362             throw new IllegalStateException("Schema Context is not available.");
 363         }
 364
 365         @Override
 366         public void verifyStructure(final NodeModification modification) throws IllegalArgumentException {
 367             throw new IllegalStateException("Schema Context is not available.");
 368         }
 369
 370     }
 371 }