opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/LocalProxyTransaction.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 java.util.function.Consumer;
  15 import javax.annotation.Nonnull;
  16 import javax.annotation.Nullable;
  17 import javax.annotation.concurrent.NotThreadSafe;
  18 import org.opendaylight.controller.cluster.access.commands.AbortLocalTransactionRequest;
  19 import org.opendaylight.controller.cluster.access.commands.AbstractLocalTransactionRequest;
  20 import org.opendaylight.controller.cluster.access.commands.CommitLocalTransactionRequest;
  21 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionRequest;
  22 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionSuccess;
  23 import org.opendaylight.controller.cluster.access.commands.IncrementTransactionSequenceRequest;
  24 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequest;
  25 import org.opendaylight.controller.cluster.access.commands.ReadTransactionRequest;
  26 import org.opendaylight.controller.cluster.access.commands.ReadTransactionSuccess;
  27 import org.opendaylight.controller.cluster.access.commands.TransactionPurgeRequest;
  28 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
  29 import org.opendaylight.controller.cluster.access.concepts.Response;
  30 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  31 import org.opendaylight.controller.cluster.datastore.util.AbstractDataTreeModificationCursor;
  32 import org.opendaylight.mdsal.common.api.ReadFailedException;
  33 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  34 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  35 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  36 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  37 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  38 import org.slf4j.Logger;
  39 import org.slf4j.LoggerFactory;
  40
  41 /**
  42  * An {@link AbstractProxyTransaction} for dispatching a transaction towards a shard leader which is co-located with
  43  * the client instance.
  44  *
  45  * <p>
  46  * It requires a {@link DataTreeSnapshot}, which is used to instantiated a new {@link DataTreeModification}. Operations
  47  * are then performed on this modification and once the transaction is submitted, the modification is sent to the shard
  48  * leader.
  49  *
  50  * <p>
  51  * This class is not thread-safe as usual with transactions. Since it does not interact with the backend until the
  52  * transaction is submitted, at which point this class gets out of the picture, this is not a cause for concern.
  53  *
  54  * @author Robert Varga
  55  */
  56 @NotThreadSafe
  57 abstract class LocalProxyTransaction extends AbstractProxyTransaction {
  58     private static final Logger LOG = LoggerFactory.getLogger(LocalProxyTransaction.class);
  59
  60     private final TransactionIdentifier identifier;
  61
  62     LocalProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier, final boolean isDone) {
  63         super(parent, isDone);
  64         this.identifier = Preconditions.checkNotNull(identifier);
  65     }
  66
  67     @Override
  68     public final TransactionIdentifier getIdentifier() {
  69         return identifier;
  70     }
  71
  72     abstract @Nonnull DataTreeSnapshot readOnlyView();
  73
  74     abstract void applyForwardedModifyTransactionRequest(ModifyTransactionRequest request,
  75             @Nullable Consumer<Response<?, ?>> callback);
  76
  77     abstract void replayModifyTransactionRequest(ModifyTransactionRequest request,
  78             @Nullable Consumer<Response<?, ?>> callback, long enqueuedTicks);
  79
  80     @Override
  81     final CheckedFuture<Boolean, ReadFailedException> doExists(final YangInstanceIdentifier path) {
  82         return Futures.immediateCheckedFuture(readOnlyView().readNode(path).isPresent());
  83     }
  84
  85     @Override
  86     final CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> doRead(final YangInstanceIdentifier path) {
  87         return Futures.immediateCheckedFuture(readOnlyView().readNode(path));
  88     }
  89
  90     @Override
  91     final AbortLocalTransactionRequest abortRequest() {
  92         return new AbortLocalTransactionRequest(identifier, localActor());
  93     }
  94
  95     @Override
  96     void handleReplayedLocalRequest(final AbstractLocalTransactionRequest<?> request,
  97             final Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
  98         if (request instanceof AbortLocalTransactionRequest) {
  99             enqueueAbort(request, callback, enqueuedTicks);
 100         } else {
 101             throw new IllegalArgumentException("Unhandled request" + request);
 102         }
 103     }
 104
 105     private boolean handleReadRequest(final TransactionRequest<?> request,
 106             final @Nullable Consumer<Response<?, ?>> callback) {
 107         // Note we delay completion of read requests to limit the scope at which the client can run, as they have
 108         // listeners, which we do not want to execute while we are reconnecting.
 109         if (request instanceof ReadTransactionRequest) {
 110             final YangInstanceIdentifier path = ((ReadTransactionRequest) request).getPath();
 111             final Optional<NormalizedNode<?, ?>> result = readOnlyView().readNode(path);
 112             if (callback != null) {
 113                 // XXX: FB does not see that callback is final, on stack and has be check for non-null.
 114                 final Consumer<Response<?, ?>> fbIsStupid = Preconditions.checkNotNull(callback);
 115                 executeInActor(() -> fbIsStupid.accept(new ReadTransactionSuccess(request.getTarget(),
 116                     request.getSequence(), result)));
 117             }
 118             return true;
 119         } else if (request instanceof ExistsTransactionRequest) {
 120             final YangInstanceIdentifier path = ((ExistsTransactionRequest) request).getPath();
 121             final boolean result = readOnlyView().readNode(path).isPresent();
 122             if (callback != null) {
 123                 // XXX: FB does not see that callback is final, on stack and has be check for non-null.
 124                 final Consumer<Response<?, ?>> fbIsStupid = Preconditions.checkNotNull(callback);
 125                 executeInActor(() -> fbIsStupid.accept(new ExistsTransactionSuccess(request.getTarget(),
 126                     request.getSequence(), result)));
 127             }
 128             return true;
 129         } else {
 130             return false;
 131         }
 132     }
 133
 134     @Override
 135     void handleReplayedRemoteRequest(final TransactionRequest<?> request,
 136             final @Nullable Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
 137         if (request instanceof ModifyTransactionRequest) {
 138             replayModifyTransactionRequest((ModifyTransactionRequest) request, callback, enqueuedTicks);
 139         } else if (handleReadRequest(request, callback)) {
 140             // No-op
 141         } else if (request instanceof TransactionPurgeRequest) {
 142             enqueuePurge(callback, enqueuedTicks);
 143         } else if (request instanceof IncrementTransactionSequenceRequest) {
 144             // Local transactions do not have non-replayable requests which would be visible to the backend,
 145             // hence we can skip sequence increments.
 146             LOG.debug("Not replaying {}", request);
 147         } else {
 148             throw new IllegalArgumentException("Unhandled request " + request);
 149         }
 150     }
 151
 152     /**
 153      * Remote-to-local equivalent of {@link #handleReplayedRemoteRequest(TransactionRequest, Consumer, long)},
 154      * except it is invoked in the forwarding path from
 155      * {@link RemoteProxyTransaction#forwardToLocal(LocalProxyTransaction, TransactionRequest, Consumer)}.
 156      *
 157      * @param request Forwarded request
 158      * @param callback Callback to be invoked once the request completes
 159      */
 160     void handleForwardedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 161         if (request instanceof ModifyTransactionRequest) {
 162             applyForwardedModifyTransactionRequest((ModifyTransactionRequest) request, callback);
 163         } else if (handleReadRequest(request, callback)) {
 164             // No-op
 165         } else if (request instanceof TransactionPurgeRequest) {
 166             enqueuePurge(callback);
 167         } else {
 168             throw new IllegalArgumentException("Unhandled request " + request);
 169         }
 170     }
 171
 172     @Override
 173     final void forwardToRemote(final RemoteProxyTransaction successor, final TransactionRequest<?> request,
 174                          final Consumer<Response<?, ?>> callback) {
 175         if (request instanceof CommitLocalTransactionRequest) {
 176             final CommitLocalTransactionRequest req = (CommitLocalTransactionRequest) request;
 177             final DataTreeModification mod = req.getModification();
 178
 179             LOG.debug("Applying modification {} to successor {}", mod, successor);
 180             mod.applyToCursor(new AbstractDataTreeModificationCursor() {
 181                 @Override
 182                 public void write(final PathArgument child, final NormalizedNode<?, ?> data) {
 183                     successor.write(current().node(child), data);
 184                 }
 185
 186                 @Override
 187                 public void merge(final PathArgument child, final NormalizedNode<?, ?> data) {
 188                     successor.merge(current().node(child), data);
 189                 }
 190
 191                 @Override
 192                 public void delete(final PathArgument child) {
 193                     successor.delete(current().node(child));
 194                 }
 195             });
 196
 197             successor.sealOnly();
 198             final ModifyTransactionRequest successorReq = successor.commitRequest(req.isCoordinated());
 199             successor.sendRequest(successorReq, callback);
 200         } else if (request instanceof AbortLocalTransactionRequest) {
 201             LOG.debug("Forwarding abort {} to successor {}", request, successor);
 202             successor.abort();
 203         } else if (request instanceof TransactionPurgeRequest) {
 204             LOG.debug("Forwarding purge {} to successor {}", request, successor);
 205             successor.enqueuePurge(callback);
 206         } else if (request instanceof ModifyTransactionRequest) {
 207             successor.handleForwardedRequest(request, callback);
 208         } else {
 209             throw new IllegalArgumentException("Unhandled request" + request);
 210         }
 211     }
 212
 213     @Override
 214     void forwardToLocal(final LocalProxyTransaction successor, final TransactionRequest<?> request,
 215             final Consumer<Response<?, ?>> callback) {
 216         if (request instanceof AbortLocalTransactionRequest) {
 217             successor.sendAbort(request, callback);
 218         } else if (request instanceof TransactionPurgeRequest) {
 219             successor.enqueuePurge(callback);
 220         } else {
 221             throw new IllegalArgumentException("Unhandled request" + request);
 222         }
 223
 224         LOG.debug("Forwarded request {} to successor {}", request, successor);
 225     }
 226
 227     void sendAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 228         sendRequest(request, callback);
 229     }
 230
 231     void enqueueAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback,
 232             final long enqueuedTicks) {
 233         enqueueRequest(request, callback, enqueuedTicks);
 234     }
 235 }