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