opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/LocalReadWriteProxyTransaction.java

   1 /*
   2  * Copyright (c) 2016 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.cluster.databroker.actors.dds;
   9
  10 import com.google.common.base.Preconditions;
  11 import com.google.common.base.Verify;
  12 import java.util.Optional;
  13 import java.util.function.BiConsumer;
  14 import java.util.function.Consumer;
  15 import java.util.function.Supplier;
  16 import javax.annotation.Nonnull;
  17 import javax.annotation.Nullable;
  18 import javax.annotation.concurrent.NotThreadSafe;
  19 import org.opendaylight.controller.cluster.access.commands.AbortLocalTransactionRequest;
  20 import org.opendaylight.controller.cluster.access.commands.AbstractLocalTransactionRequest;
  21 import org.opendaylight.controller.cluster.access.commands.CommitLocalTransactionRequest;
  22 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequest;
  23 import org.opendaylight.controller.cluster.access.commands.PersistenceProtocol;
  24 import org.opendaylight.controller.cluster.access.commands.TransactionAbortRequest;
  25 import org.opendaylight.controller.cluster.access.commands.TransactionDelete;
  26 import org.opendaylight.controller.cluster.access.commands.TransactionDoCommitRequest;
  27 import org.opendaylight.controller.cluster.access.commands.TransactionMerge;
  28 import org.opendaylight.controller.cluster.access.commands.TransactionModification;
  29 import org.opendaylight.controller.cluster.access.commands.TransactionPreCommitRequest;
  30 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
  31 import org.opendaylight.controller.cluster.access.commands.TransactionWrite;
  32 import org.opendaylight.controller.cluster.access.concepts.Response;
  33 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  34 import org.opendaylight.controller.cluster.datastore.util.AbstractDataTreeModificationCursor;
  35 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  36 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  37 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  38 import org.opendaylight.yangtools.yang.data.api.schema.tree.CursorAwareDataTreeModification;
  39 import org.opendaylight.yangtools.yang.data.api.schema.tree.CursorAwareDataTreeSnapshot;
  40 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  41 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModificationCursor;
  42 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  43 import org.slf4j.Logger;
  44 import org.slf4j.LoggerFactory;
  45
  46 /**
  47  * An {@link AbstractProxyTransaction} for dispatching a transaction towards a shard leader which is co-located with
  48  * the client instance.
  49  *
  50  * <p>
  51  * It requires a {@link DataTreeSnapshot}, which is used to instantiated a new {@link DataTreeModification}. Operations
  52  * are then performed on this modification and once the transaction is submitted, the modification is sent to the shard
  53  * leader.
  54  *
  55  * <p>
  56  * This class is not thread-safe as usual with transactions. Since it does not interact with the backend until the
  57  * transaction is submitted, at which point this class gets out of the picture, this is not a cause for concern.
  58  *
  59  * @author Robert Varga
  60  */
  61 @NotThreadSafe
  62 final class LocalReadWriteProxyTransaction extends LocalProxyTransaction {
  63     private static final Logger LOG = LoggerFactory.getLogger(LocalReadWriteProxyTransaction.class);
  64
  65     /**
  66      * This field needs to be accessed via {@link #getModification()}, which performs state checking to ensure
  67      * the modification can actually be accessed.
  68      */
  69     private final CursorAwareDataTreeModification modification;
  70
  71     private Supplier<? extends RuntimeException> closedException;
  72
  73     private CursorAwareDataTreeModification sealedModification;
  74
  75     /**
  76      * Recorded failure from previous operations. Normally we would want to propagate the error directly to the
  77      * offending call site, but that exposes inconsistency in behavior during initial connection, when we go through
  78      * {@link RemoteProxyTransaction}, which detects this sort of issues at canCommit/directCommit time on the backend.
  79      *
  80      * <p>
  81      * We therefore do not report incurred exceptions directly, but report them once the user attempts to commit
  82      * this transaction.
  83      */
  84     private Exception recordedFailure;
  85
  86     LocalReadWriteProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier,
  87         final DataTreeSnapshot snapshot) {
  88         super(parent, identifier, false);
  89         this.modification = (CursorAwareDataTreeModification) snapshot.newModification();
  90     }
  91
  92     LocalReadWriteProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier) {
  93         super(parent, identifier, true);
  94         // This is DONE transaction, this should never be touched
  95         this.modification = null;
  96     }
  97
  98     @Override
  99     boolean isSnapshotOnly() {
 100         return false;
 101     }
 102
 103     @Override
 104     CursorAwareDataTreeSnapshot readOnlyView() {
 105         return getModification();
 106     }
 107
 108     @Override
 109     @SuppressWarnings("checkstyle:IllegalCatch")
 110     void doDelete(final YangInstanceIdentifier path) {
 111         final CursorAwareDataTreeModification mod = getModification();
 112         if (recordedFailure != null) {
 113             LOG.debug("Transaction {} recorded failure, ignoring delete of {}", getIdentifier(), path);
 114             return;
 115         }
 116
 117         try {
 118             mod.delete(path);
 119         } catch (Exception e) {
 120             LOG.debug("Transaction {} delete on {} incurred failure, delaying it until commit", getIdentifier(), path,
 121                 e);
 122             recordedFailure = e;
 123         }
 124     }
 125
 126     @Override
 127     @SuppressWarnings("checkstyle:IllegalCatch")
 128     void doMerge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
 129         final CursorAwareDataTreeModification mod = getModification();
 130         if (recordedFailure != null) {
 131             LOG.debug("Transaction {} recorded failure, ignoring merge to {}", getIdentifier(), path);
 132             return;
 133         }
 134
 135         try {
 136             mod.merge(path, data);
 137         } catch (Exception e) {
 138             LOG.debug("Transaction {} merge to {} incurred failure, delaying it until commit", getIdentifier(), path,
 139                 e);
 140             recordedFailure = e;
 141         }
 142     }
 143
 144     @Override
 145     @SuppressWarnings("checkstyle:IllegalCatch")
 146     void doWrite(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
 147         final CursorAwareDataTreeModification mod = getModification();
 148         if (recordedFailure != null) {
 149             LOG.debug("Transaction {} recorded failure, ignoring write to {}", getIdentifier(), path);
 150             return;
 151         }
 152
 153         try {
 154             mod.write(path, data);
 155         } catch (Exception e) {
 156             LOG.debug("Transaction {} write to {} incurred failure, delaying it until commit", getIdentifier(), path,
 157                 e);
 158             recordedFailure = e;
 159         }
 160     }
 161
 162     private RuntimeException abortedException() {
 163         return new IllegalStateException("Tracker " + getIdentifier() + " has been aborted");
 164     }
 165
 166     private RuntimeException submittedException() {
 167         return new IllegalStateException("Tracker " + getIdentifier() + " has been submitted");
 168     }
 169
 170     @Override
 171     CommitLocalTransactionRequest commitRequest(final boolean coordinated) {
 172         final CursorAwareDataTreeModification mod = getModification();
 173         final CommitLocalTransactionRequest ret = new CommitLocalTransactionRequest(getIdentifier(), nextSequence(),
 174             localActor(), mod, recordedFailure, coordinated);
 175         closedException = this::submittedException;
 176         return ret;
 177     }
 178
 179     @Override
 180     void doSeal() {
 181         Preconditions.checkState(sealedModification == null, "Transaction %s is already sealed", getIdentifier());
 182         final CursorAwareDataTreeModification mod = getModification();
 183         mod.ready();
 184         sealedModification = mod;
 185     }
 186
 187     @Override
 188     void flushState(final AbstractProxyTransaction successor) {
 189         sealedModification.applyToCursor(new AbstractDataTreeModificationCursor() {
 190             @Override
 191             public void write(final PathArgument child, final NormalizedNode<?, ?> data) {
 192                 successor.write(current().node(child), data);
 193             }
 194
 195             @Override
 196             public void merge(final PathArgument child, final NormalizedNode<?, ?> data) {
 197                 successor.merge(current().node(child), data);
 198             }
 199
 200             @Override
 201             public void delete(final PathArgument child) {
 202                 successor.delete(current().node(child));
 203             }
 204         });
 205     }
 206
 207     DataTreeSnapshot getSnapshot() {
 208         Preconditions.checkState(sealedModification != null, "Proxy %s is not sealed yet", getIdentifier());
 209         return sealedModification;
 210     }
 211
 212     @Override
 213     void applyForwardedModifyTransactionRequest(final ModifyTransactionRequest request,
 214             final @Nullable Consumer<Response<?, ?>> callback) {
 215         commonModifyTransactionRequest(request, callback, this::sendRequest);
 216     }
 217
 218     @Override
 219     void replayModifyTransactionRequest(final ModifyTransactionRequest request,
 220             final @Nullable Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
 221         commonModifyTransactionRequest(request, callback, (req, cb) -> enqueueRequest(req, cb, enqueuedTicks));
 222     }
 223
 224     private void commonModifyTransactionRequest(final ModifyTransactionRequest request,
 225             final @Nullable Consumer<Response<?, ?>> callback,
 226             final BiConsumer<TransactionRequest<?>, Consumer<Response<?, ?>>> sendMethod) {
 227         for (final TransactionModification mod : request.getModifications()) {
 228             if (mod instanceof TransactionWrite) {
 229                 write(mod.getPath(), ((TransactionWrite)mod).getData());
 230             } else if (mod instanceof TransactionMerge) {
 231                 merge(mod.getPath(), ((TransactionMerge)mod).getData());
 232             } else if (mod instanceof TransactionDelete) {
 233                 delete(mod.getPath());
 234             } else {
 235                 throw new IllegalArgumentException("Unsupported modification " + mod);
 236             }
 237         }
 238
 239         final Optional<PersistenceProtocol> maybeProtocol = request.getPersistenceProtocol();
 240         if (maybeProtocol.isPresent()) {
 241             Verify.verify(callback != null, "Request {} has null callback", request);
 242             ensureSealed();
 243
 244             switch (maybeProtocol.get()) {
 245                 case ABORT:
 246                     sendMethod.accept(new AbortLocalTransactionRequest(getIdentifier(), localActor()), callback);
 247                     break;
 248                 case READY:
 249                     // No-op, as we have already issued a seal()
 250                     break;
 251                 case SIMPLE:
 252                     sendMethod.accept(commitRequest(false), callback);
 253                     break;
 254                 case THREE_PHASE:
 255                     sendMethod.accept(commitRequest(true), callback);
 256                     break;
 257                 default:
 258                     throw new IllegalArgumentException("Unhandled protocol " + maybeProtocol.get());
 259             }
 260         }
 261     }
 262
 263     @Override
 264     void handleReplayedLocalRequest(final AbstractLocalTransactionRequest<?> request,
 265             final Consumer<Response<?, ?>> callback, final long now) {
 266         if (request instanceof CommitLocalTransactionRequest) {
 267             sendCommit((CommitLocalTransactionRequest) request, callback);
 268         } else {
 269             super.handleReplayedLocalRequest(request, callback, now);
 270         }
 271     }
 272
 273     @Override
 274     void handleReplayedRemoteRequest(final TransactionRequest<?> request,
 275             final @Nullable Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
 276         LOG.debug("Applying replayed request {}", request);
 277
 278         if (request instanceof TransactionPreCommitRequest) {
 279             enqueueRequest(new TransactionPreCommitRequest(getIdentifier(), nextSequence(), localActor()), callback,
 280                 enqueuedTicks);
 281         } else if (request instanceof TransactionDoCommitRequest) {
 282             enqueueRequest(new TransactionDoCommitRequest(getIdentifier(), nextSequence(), localActor()), callback,
 283                 enqueuedTicks);
 284         } else if (request instanceof TransactionAbortRequest) {
 285             enqueueDoAbort(callback, enqueuedTicks);
 286         } else {
 287             super.handleReplayedRemoteRequest(request, callback, enqueuedTicks);
 288         }
 289     }
 290
 291     @Override
 292     void handleForwardedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 293         LOG.debug("Applying forwarded request {}", request);
 294
 295         if (request instanceof TransactionPreCommitRequest) {
 296             sendRequest(new TransactionPreCommitRequest(getIdentifier(), nextSequence(), localActor()), callback);
 297         } else if (request instanceof TransactionDoCommitRequest) {
 298             sendRequest(new TransactionDoCommitRequest(getIdentifier(), nextSequence(), localActor()), callback);
 299         } else if (request instanceof TransactionAbortRequest) {
 300             sendDoAbort(callback);
 301         } else {
 302             super.handleForwardedRemoteRequest(request, callback);
 303         }
 304     }
 305
 306     @Override
 307     void forwardToLocal(final LocalProxyTransaction successor, final TransactionRequest<?> request,
 308             final Consumer<Response<?, ?>> callback) {
 309         if (request instanceof CommitLocalTransactionRequest) {
 310             Verify.verify(successor instanceof LocalReadWriteProxyTransaction);
 311             ((LocalReadWriteProxyTransaction) successor).sendCommit((CommitLocalTransactionRequest)request, callback);
 312             LOG.debug("Forwarded request {} to successor {}", request, successor);
 313         } else {
 314             super.forwardToLocal(successor, request, callback);
 315         }
 316     }
 317
 318     @Override
 319     void sendAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 320         super.sendAbort(request, callback);
 321         closedException = this::abortedException;
 322     }
 323
 324     @Override
 325     void enqueueAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback,
 326             final long enqueuedTicks) {
 327         super.enqueueAbort(request, callback, enqueuedTicks);
 328         closedException = this::abortedException;
 329     }
 330
 331     private @Nonnull CursorAwareDataTreeModification getModification() {
 332         if (closedException != null) {
 333             throw closedException.get();
 334         }
 335
 336         return Preconditions.checkNotNull(modification, "Transaction %s is DONE", getIdentifier());
 337     }
 338
 339     private void sendCommit(final CommitLocalTransactionRequest request, final Consumer<Response<?, ?>> callback) {
 340         // Rebase old modification on new data tree.
 341         final CursorAwareDataTreeModification mod = getModification();
 342
 343         try (DataTreeModificationCursor cursor = mod.createCursor(YangInstanceIdentifier.EMPTY)) {
 344             request.getModification().applyToCursor(cursor);
 345         }
 346
 347         ensureSealed();
 348         sendRequest(commitRequest(request.isCoordinated()), callback);
 349     }
 350 }