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     private void sealModification() {
 180         Preconditions.checkState(sealedModification == null, "Transaction %s is already sealed", this);
 181         final CursorAwareDataTreeModification mod = getModification();
 182         mod.ready();
 183         sealedModification = mod;
 184     }
 185
 186     @Override
 187     void sealOnly() {
 188         sealModification();
 189         super.sealOnly();
 190     }
 191
 192     @Override
 193     boolean sealAndSend(final com.google.common.base.Optional<Long> enqueuedTicks) {
 194         sealModification();
 195         return super.sealAndSend(enqueuedTicks);
 196     }
 197
 198     @Override
 199     void flushState(final AbstractProxyTransaction successor) {
 200         sealedModification.applyToCursor(new AbstractDataTreeModificationCursor() {
 201             @Override
 202             public void write(final PathArgument child, final NormalizedNode<?, ?> data) {
 203                 successor.write(current().node(child), data);
 204             }
 205
 206             @Override
 207             public void merge(final PathArgument child, final NormalizedNode<?, ?> data) {
 208                 successor.merge(current().node(child), data);
 209             }
 210
 211             @Override
 212             public void delete(final PathArgument child) {
 213                 successor.delete(current().node(child));
 214             }
 215         });
 216     }
 217
 218     DataTreeSnapshot getSnapshot() {
 219         Preconditions.checkState(sealedModification != null, "Proxy %s is not sealed yet", getIdentifier());
 220         return sealedModification;
 221     }
 222
 223     @Override
 224     void applyForwardedModifyTransactionRequest(final ModifyTransactionRequest request,
 225             final @Nullable Consumer<Response<?, ?>> callback) {
 226         commonModifyTransactionRequest(request, callback, this::sendRequest);
 227     }
 228
 229     @Override
 230     void replayModifyTransactionRequest(final ModifyTransactionRequest request,
 231             final @Nullable Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
 232         commonModifyTransactionRequest(request, callback, (req, cb) -> enqueueRequest(req, cb, enqueuedTicks));
 233     }
 234
 235     private void commonModifyTransactionRequest(final ModifyTransactionRequest request,
 236             final @Nullable Consumer<Response<?, ?>> callback,
 237             final BiConsumer<TransactionRequest<?>, Consumer<Response<?, ?>>> sendMethod) {
 238         for (final TransactionModification mod : request.getModifications()) {
 239             if (mod instanceof TransactionWrite) {
 240                 write(mod.getPath(), ((TransactionWrite)mod).getData());
 241             } else if (mod instanceof TransactionMerge) {
 242                 merge(mod.getPath(), ((TransactionMerge)mod).getData());
 243             } else if (mod instanceof TransactionDelete) {
 244                 delete(mod.getPath());
 245             } else {
 246                 throw new IllegalArgumentException("Unsupported modification " + mod);
 247             }
 248         }
 249
 250         final Optional<PersistenceProtocol> maybeProtocol = request.getPersistenceProtocol();
 251         if (maybeProtocol.isPresent()) {
 252             Verify.verify(callback != null, "Request %s has null callback", request);
 253             if (markSealed()) {
 254                 sealOnly();
 255             }
 256
 257             switch (maybeProtocol.get()) {
 258                 case ABORT:
 259                     sendMethod.accept(new AbortLocalTransactionRequest(getIdentifier(), localActor()), callback);
 260                     break;
 261                 case READY:
 262                     // No-op, as we have already issued a sealOnly() and we are not transmitting anything
 263                     break;
 264                 case SIMPLE:
 265                     sendMethod.accept(commitRequest(false), callback);
 266                     break;
 267                 case THREE_PHASE:
 268                     sendMethod.accept(commitRequest(true), callback);
 269                     break;
 270                 default:
 271                     throw new IllegalArgumentException("Unhandled protocol " + maybeProtocol.get());
 272             }
 273         }
 274     }
 275
 276     @Override
 277     void handleReplayedLocalRequest(final AbstractLocalTransactionRequest<?> request,
 278             final Consumer<Response<?, ?>> callback, final long now) {
 279         if (request instanceof CommitLocalTransactionRequest) {
 280             enqueueRequest(rebaseCommit((CommitLocalTransactionRequest)request), callback, now);
 281         } else {
 282             super.handleReplayedLocalRequest(request, callback, now);
 283         }
 284     }
 285
 286     @Override
 287     void handleReplayedRemoteRequest(final TransactionRequest<?> request,
 288             final @Nullable Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
 289         LOG.debug("Applying replayed request {}", request);
 290
 291         if (request instanceof TransactionPreCommitRequest) {
 292             enqueueRequest(new TransactionPreCommitRequest(getIdentifier(), nextSequence(), localActor()), callback,
 293                 enqueuedTicks);
 294         } else if (request instanceof TransactionDoCommitRequest) {
 295             enqueueRequest(new TransactionDoCommitRequest(getIdentifier(), nextSequence(), localActor()), callback,
 296                 enqueuedTicks);
 297         } else if (request instanceof TransactionAbortRequest) {
 298             enqueueDoAbort(callback, enqueuedTicks);
 299         } else {
 300             super.handleReplayedRemoteRequest(request, callback, enqueuedTicks);
 301         }
 302     }
 303
 304     @Override
 305     void handleForwardedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 306         LOG.debug("Applying forwarded request {}", request);
 307
 308         if (request instanceof TransactionPreCommitRequest) {
 309             sendRequest(new TransactionPreCommitRequest(getIdentifier(), nextSequence(), localActor()), callback);
 310         } else if (request instanceof TransactionDoCommitRequest) {
 311             sendRequest(new TransactionDoCommitRequest(getIdentifier(), nextSequence(), localActor()), callback);
 312         } else if (request instanceof TransactionAbortRequest) {
 313             sendDoAbort(callback);
 314         } else {
 315             super.handleForwardedRemoteRequest(request, callback);
 316         }
 317     }
 318
 319     @Override
 320     void forwardToLocal(final LocalProxyTransaction successor, final TransactionRequest<?> request,
 321             final Consumer<Response<?, ?>> callback) {
 322         if (request instanceof CommitLocalTransactionRequest) {
 323             Verify.verify(successor instanceof LocalReadWriteProxyTransaction);
 324             ((LocalReadWriteProxyTransaction) successor).sendRebased((CommitLocalTransactionRequest)request, callback);
 325             LOG.debug("Forwarded request {} to successor {}", request, successor);
 326         } else {
 327             super.forwardToLocal(successor, request, callback);
 328         }
 329     }
 330
 331     @Override
 332     void sendAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 333         super.sendAbort(request, callback);
 334         closedException = this::abortedException;
 335     }
 336
 337     @Override
 338     void enqueueAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback,
 339             final long enqueuedTicks) {
 340         super.enqueueAbort(request, callback, enqueuedTicks);
 341         closedException = this::abortedException;
 342     }
 343
 344     private @Nonnull CursorAwareDataTreeModification getModification() {
 345         if (closedException != null) {
 346             throw closedException.get();
 347         }
 348
 349         return Preconditions.checkNotNull(modification, "Transaction %s is DONE", getIdentifier());
 350     }
 351
 352     private void sendRebased(final CommitLocalTransactionRequest request, final Consumer<Response<?, ?>> callback) {
 353         sendRequest(rebaseCommit(request), callback);
 354     }
 355
 356     private CommitLocalTransactionRequest rebaseCommit(final CommitLocalTransactionRequest request) {
 357         // Rebase old modification on new data tree.
 358         final CursorAwareDataTreeModification mod = getModification();
 359
 360         try (DataTreeModificationCursor cursor = mod.createCursor(YangInstanceIdentifier.EMPTY)) {
 361             request.getModification().applyToCursor(cursor);
 362         }
 363
 364         if (markSealed()) {
 365             sealOnly();
 366         }
 367
 368         return commitRequest(request.isCoordinated());
 369     }
 370 }