opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/RemoteProxyTransaction.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.Optional;
  11 import com.google.common.base.Preconditions;
  12 import com.google.common.util.concurrent.CheckedFuture;
  13 import com.google.common.util.concurrent.Futures;
  14 import com.google.common.util.concurrent.ListenableFuture;
  15 import com.google.common.util.concurrent.SettableFuture;
  16 import java.util.function.Consumer;
  17 import javax.annotation.Nullable;
  18 import org.opendaylight.controller.cluster.access.commands.AbstractReadTransactionRequest;
  19 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionRequest;
  20 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionSuccess;
  21 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequest;
  22 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequestBuilder;
  23 import org.opendaylight.controller.cluster.access.commands.PersistenceProtocol;
  24 import org.opendaylight.controller.cluster.access.commands.ReadTransactionRequest;
  25 import org.opendaylight.controller.cluster.access.commands.ReadTransactionSuccess;
  26 import org.opendaylight.controller.cluster.access.commands.TransactionAbortRequest;
  27 import org.opendaylight.controller.cluster.access.commands.TransactionDelete;
  28 import org.opendaylight.controller.cluster.access.commands.TransactionDoCommitRequest;
  29 import org.opendaylight.controller.cluster.access.commands.TransactionMerge;
  30 import org.opendaylight.controller.cluster.access.commands.TransactionModification;
  31 import org.opendaylight.controller.cluster.access.commands.TransactionPreCommitRequest;
  32 import org.opendaylight.controller.cluster.access.commands.TransactionPurgeRequest;
  33 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
  34 import org.opendaylight.controller.cluster.access.commands.TransactionSuccess;
  35 import org.opendaylight.controller.cluster.access.commands.TransactionWrite;
  36 import org.opendaylight.controller.cluster.access.concepts.RequestFailure;
  37 import org.opendaylight.controller.cluster.access.concepts.Response;
  38 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  39 import org.opendaylight.mdsal.common.api.ReadFailedException;
  40 import org.opendaylight.yangtools.util.concurrent.MappingCheckedFuture;
  41 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  42 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  43 import org.slf4j.Logger;
  44 import org.slf4j.LoggerFactory;
  45
  46 /**
  47  * An {@link AbstractProxyTransaction} for dispatching a transaction towards a shard leader whose location is currently
  48  * not known or is known to be not co-located with the client.
  49  *
  50  * <p>
  51  * It packages operations and sends them via the client actor queue to the shard leader. That queue is responsible for
  52  * maintaining any submitted operations until the leader is discovered.
  53  *
  54  * <p>
  55  * This class is not safe to access from multiple application threads, as is usual for transactions. Its internal state
  56  * transitions based on backend responses are thread-safe.
  57  *
  58  * @author Robert Varga
  59  */
  60 final class RemoteProxyTransaction extends AbstractProxyTransaction {
  61     private static final Logger LOG = LoggerFactory.getLogger(RemoteProxyTransaction.class);
  62
  63     // FIXME: make this tuneable
  64     private static final int REQUEST_MAX_MODIFICATIONS = 1000;
  65
  66     private final ModifyTransactionRequestBuilder builder;
  67     private final boolean sendReadyOnSeal;
  68     private final boolean snapshotOnly;
  69
  70     private boolean builderBusy;
  71
  72     private volatile Exception operationFailure;
  73
  74
  75     RemoteProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier,
  76             final boolean snapshotOnly, final boolean sendReadyOnSeal) {
  77         super(parent);
  78         this.snapshotOnly = snapshotOnly;
  79         this.sendReadyOnSeal = sendReadyOnSeal;
  80         builder = new ModifyTransactionRequestBuilder(identifier, localActor());
  81     }
  82
  83     @Override
  84     boolean isSnapshotOnly() {
  85         return snapshotOnly;
  86     }
  87
  88     @Override
  89     public TransactionIdentifier getIdentifier() {
  90         return builder.getIdentifier();
  91     }
  92
  93     @Override
  94     void doDelete(final YangInstanceIdentifier path) {
  95         appendModification(new TransactionDelete(path));
  96     }
  97
  98     @Override
  99     void doMerge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
 100         appendModification(new TransactionMerge(path, data));
 101     }
 102
 103     @Override
 104     void doWrite(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
 105         appendModification(new TransactionWrite(path, data));
 106     }
 107
 108     private <T> CheckedFuture<T, ReadFailedException> sendReadRequest(final AbstractReadTransactionRequest<?> request,
 109             final Consumer<Response<?, ?>> completer, final ListenableFuture<T> future) {
 110         // Check if a previous operation failed. If it has, do not bother sending anything and report a failure
 111         final Exception local = operationFailure;
 112         if (local != null) {
 113             return Futures.immediateFailedCheckedFuture(new ReadFailedException("Previous operation failed", local));
 114         }
 115
 116         // Make sure we send any modifications before issuing a read
 117         ensureFlushedBuider();
 118         sendRequest(request, completer);
 119         return MappingCheckedFuture.create(future, ReadFailedException.MAPPER);
 120     }
 121
 122     @Override
 123     CheckedFuture<Boolean, ReadFailedException> doExists(final YangInstanceIdentifier path) {
 124         final SettableFuture<Boolean> future = SettableFuture.create();
 125         return sendReadRequest(new ExistsTransactionRequest(getIdentifier(), nextSequence(), localActor(), path,
 126             isSnapshotOnly()), t -> completeExists(future, t), future);
 127     }
 128
 129     @Override
 130     CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> doRead(final YangInstanceIdentifier path) {
 131         final SettableFuture<Optional<NormalizedNode<?, ?>>> future = SettableFuture.create();
 132         return sendReadRequest(new ReadTransactionRequest(getIdentifier(), nextSequence(), localActor(), path,
 133             isSnapshotOnly()), t -> completeRead(future, t), future);
 134     }
 135
 136     @Override
 137     void doAbort() {
 138         ensureInitializedBuilder();
 139         builder.setAbort();
 140         flushBuilder();
 141     }
 142
 143     private void ensureInitializedBuilder() {
 144         if (!builderBusy) {
 145             builder.setSequence(nextSequence());
 146             builderBusy = true;
 147         }
 148     }
 149
 150     private void ensureFlushedBuider() {
 151         if (builderBusy) {
 152             flushBuilder();
 153         }
 154     }
 155
 156     private void flushBuilder() {
 157         final ModifyTransactionRequest request = builder.build();
 158         builderBusy = false;
 159
 160         sendModification(request);
 161     }
 162
 163     private void sendModification(final TransactionRequest<?> request) {
 164         sendRequest(request, response -> completeModify(request, response));
 165     }
 166
 167     @Override
 168     void handleForwardedRemoteRequest(final TransactionRequest<?> request,
 169             final @Nullable Consumer<Response<?, ?>> callback) {
 170         nextSequence();
 171
 172         if (callback == null) {
 173             sendModification(request);
 174             return;
 175         }
 176
 177         /*
 178          * FindBugs is utterly stupid, as it does not recognize the fact that we have checked for null
 179          * and reports NP_PARAMETER_MUST_BE_NONNULL_BUT_MARKED_AS_NULLABLE in the lambda below.
 180          */
 181         final Consumer<Response<?, ?>> findBugsIsStupid = callback;
 182
 183         // FIXME: do not use sendRequest() once we have throttling in place, as we have already waited the
 184         //        period required to get into the queue.
 185         sendRequest(request, response -> {
 186             findBugsIsStupid.accept(Preconditions.checkNotNull(response));
 187             completeModify(request, response);
 188         });
 189     }
 190
 191     private void appendModification(final TransactionModification modification) {
 192         if (operationFailure == null) {
 193             ensureInitializedBuilder();
 194
 195             builder.addModification(modification);
 196             if (builder.size() >= REQUEST_MAX_MODIFICATIONS) {
 197                 flushBuilder();
 198             }
 199         } else {
 200             LOG.debug("Transaction {} failed, not attempting further transactions", getIdentifier());
 201         }
 202     }
 203
 204     private void completeModify(final TransactionRequest<?> request, final Response<?, ?> response) {
 205         LOG.debug("Modification request {} completed with {}", request, response);
 206
 207         if (response instanceof TransactionSuccess) {
 208             // Happy path
 209             recordSuccessfulRequest(request);
 210         } else {
 211             recordFailedResponse(response);
 212         }
 213     }
 214
 215     private Exception recordFailedResponse(final Response<?, ?> response) {
 216         final Exception failure;
 217         if (response instanceof RequestFailure) {
 218             failure = ((RequestFailure<?, ?>) response).getCause();
 219         } else {
 220             LOG.warn("Unhandled response {}", response);
 221             failure = new IllegalArgumentException("Unhandled response " + response.getClass());
 222         }
 223
 224         if (operationFailure == null) {
 225             LOG.debug("Transaction {} failed", getIdentifier(), failure);
 226             operationFailure = failure;
 227         }
 228         return failure;
 229     }
 230
 231     private void failFuture(final SettableFuture<?> future, final Response<?, ?> response) {
 232         future.setException(recordFailedResponse(response));
 233     }
 234
 235     private void completeExists(final SettableFuture<Boolean> future, final Response<?, ?> response) {
 236         LOG.debug("Exists request completed with {}", response);
 237
 238         if (response instanceof ExistsTransactionSuccess) {
 239             future.set(((ExistsTransactionSuccess) response).getExists());
 240         } else {
 241             failFuture(future, response);
 242         }
 243
 244         recordFinishedRequest();
 245     }
 246
 247     private void completeRead(final SettableFuture<Optional<NormalizedNode<?, ?>>> future,
 248             final Response<?, ?> response) {
 249         LOG.debug("Read request completed with {}", response);
 250
 251         if (response instanceof ReadTransactionSuccess) {
 252             future.set(((ReadTransactionSuccess) response).getData());
 253         } else {
 254             failFuture(future, response);
 255         }
 256
 257         recordFinishedRequest();
 258     }
 259
 260     @Override
 261     ModifyTransactionRequest commitRequest(final boolean coordinated) {
 262         ensureInitializedBuilder();
 263         builder.setCommit(coordinated);
 264
 265         final ModifyTransactionRequest ret = builder.build();
 266         builderBusy = false;
 267         return ret;
 268     }
 269
 270     @Override
 271     void doSeal() {
 272         if (sendReadyOnSeal) {
 273             ensureInitializedBuilder();
 274             builder.setReady();
 275             flushBuilder();
 276         }
 277     }
 278
 279     @Override
 280     void flushState(final AbstractProxyTransaction successor) {
 281         if (builderBusy) {
 282             final ModifyTransactionRequest request = builder.build();
 283             builderBusy = false;
 284             successor.handleForwardedRemoteRequest(request, null);
 285         }
 286     }
 287
 288     @Override
 289     void forwardToRemote(final RemoteProxyTransaction successor, final TransactionRequest<?> request,
 290             final Consumer<Response<?, ?>> callback) {
 291         successor.handleForwardedRequest(request, callback);
 292     }
 293
 294     private void handleForwardedRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 295         if (request instanceof ModifyTransactionRequest) {
 296             final ModifyTransactionRequest req = (ModifyTransactionRequest) request;
 297
 298             req.getModifications().forEach(this::appendModification);
 299
 300             final java.util.Optional<PersistenceProtocol> maybeProto = req.getPersistenceProtocol();
 301             if (maybeProto.isPresent()) {
 302                 ensureSealed();
 303
 304                 switch (maybeProto.get()) {
 305                     case ABORT:
 306                         sendAbort(callback);
 307                         break;
 308                     case SIMPLE:
 309                         sendRequest(commitRequest(false), callback);
 310                         break;
 311                     case THREE_PHASE:
 312                         sendRequest(commitRequest(true), callback);
 313                         break;
 314                     case READY:
 315                         //no op
 316                         break;
 317                     default:
 318                         throw new IllegalArgumentException("Unhandled protocol " + maybeProto.get());
 319                 }
 320             }
 321         } else if (request instanceof ReadTransactionRequest) {
 322             ensureFlushedBuider();
 323             sendRequest(new ReadTransactionRequest(getIdentifier(), nextSequence(), localActor(),
 324                 ((ReadTransactionRequest) request).getPath(), isSnapshotOnly()), callback);
 325         } else if (request instanceof ExistsTransactionRequest) {
 326             ensureFlushedBuider();
 327             sendRequest(new ExistsTransactionRequest(getIdentifier(), nextSequence(), localActor(),
 328                 ((ExistsTransactionRequest) request).getPath(), isSnapshotOnly()), callback);
 329         } else if (request instanceof TransactionPreCommitRequest) {
 330             ensureFlushedBuider();
 331             sendRequest(new TransactionPreCommitRequest(getIdentifier(), nextSequence(), localActor()), callback);
 332         } else if (request instanceof TransactionDoCommitRequest) {
 333             ensureFlushedBuider();
 334             sendRequest(new TransactionDoCommitRequest(getIdentifier(), nextSequence(), localActor()), callback);
 335         } else if (request instanceof TransactionAbortRequest) {
 336             ensureFlushedBuider();
 337             sendAbort(callback);
 338         } else if (request instanceof TransactionPurgeRequest) {
 339             purge();
 340         } else {
 341             throw new IllegalArgumentException("Unhandled request {}" + request);
 342         }
 343     }
 344
 345     @Override
 346     void forwardToLocal(final LocalProxyTransaction successor, final TransactionRequest<?> request,
 347             final Consumer<Response<?, ?>> callback) {
 348         successor.handleForwardedRemoteRequest(request, callback);
 349     }
 350 }