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 static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.util.concurrent.FluentFuture;
  14 import java.util.Optional;
  15 import java.util.function.Consumer;
  16 import org.eclipse.jdt.annotation.NonNull;
  17 import org.eclipse.jdt.annotation.Nullable;
  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.yangtools.util.concurrent.FluentFutures;
  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. This class is NOT thread-safe.
  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 abstract class LocalProxyTransaction extends AbstractProxyTransaction {
  57     private static final Logger LOG = LoggerFactory.getLogger(LocalProxyTransaction.class);
  58
  59     private final TransactionIdentifier identifier;
  60
  61     LocalProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier, final boolean isDone) {
  62         super(parent, isDone);
  63         this.identifier = requireNonNull(identifier);
  64     }
  65
  66     @Override
  67     public final TransactionIdentifier getIdentifier() {
  68         return identifier;
  69     }
  70
  71     abstract @NonNull DataTreeSnapshot readOnlyView();
  72
  73     abstract void applyForwardedModifyTransactionRequest(ModifyTransactionRequest request,
  74             @Nullable Consumer<Response<?, ?>> callback);
  75
  76     abstract void replayModifyTransactionRequest(ModifyTransactionRequest request,
  77             @Nullable Consumer<Response<?, ?>> callback, long enqueuedTicks);
  78
  79     @Override
  80     final FluentFuture<Boolean> doExists(final YangInstanceIdentifier path) {
  81         return FluentFutures.immediateFluentFuture(readOnlyView().readNode(path).isPresent());
  82     }
  83
  84     @Override
  85     final FluentFuture<Optional<NormalizedNode<?, ?>>> doRead(final YangInstanceIdentifier path) {
  86         return FluentFutures.immediateFluentFuture(readOnlyView().readNode(path));
  87     }
  88
  89     @Override
  90     final AbortLocalTransactionRequest abortRequest() {
  91         return new AbortLocalTransactionRequest(identifier, localActor());
  92     }
  93
  94     @Override
  95     void handleReplayedLocalRequest(final AbstractLocalTransactionRequest<?> request,
  96             final Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
  97         if (request instanceof AbortLocalTransactionRequest) {
  98             enqueueAbort(request, callback, enqueuedTicks);
  99         } else {
 100             throw new IllegalArgumentException("Unhandled request" + request);
 101         }
 102     }
 103
 104     private boolean handleReadRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 105         // Note we delay completion of read requests to limit the scope at which the client can run, as they have
 106         // listeners, which we do not want to execute while we are reconnecting.
 107         if (request instanceof ReadTransactionRequest) {
 108             final YangInstanceIdentifier path = ((ReadTransactionRequest) request).getPath();
 109             final Optional<NormalizedNode<?, ?>> result = readOnlyView().readNode(path);
 110             if (callback != null) {
 111                 // XXX: FB does not see that callback is final, on stack and has be check for non-null.
 112                 final Consumer<Response<?, ?>> fbIsStupid = Preconditions.checkNotNull(callback);
 113                 executeInActor(() -> fbIsStupid.accept(new ReadTransactionSuccess(request.getTarget(),
 114                     request.getSequence(), result)));
 115             }
 116             return true;
 117         } else if (request instanceof ExistsTransactionRequest) {
 118             final YangInstanceIdentifier path = ((ExistsTransactionRequest) request).getPath();
 119             final boolean result = readOnlyView().readNode(path).isPresent();
 120             if (callback != null) {
 121                 // XXX: FB does not see that callback is final, on stack and has be check for non-null.
 122                 final Consumer<Response<?, ?>> fbIsStupid = Preconditions.checkNotNull(callback);
 123                 executeInActor(() -> fbIsStupid.accept(new ExistsTransactionSuccess(request.getTarget(),
 124                     request.getSequence(), result)));
 125             }
 126             return true;
 127         } else {
 128             return false;
 129         }
 130     }
 131
 132     @Override
 133     void handleReplayedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback,
 134             final long enqueuedTicks) {
 135         if (request instanceof ModifyTransactionRequest) {
 136             replayModifyTransactionRequest((ModifyTransactionRequest) request, callback, enqueuedTicks);
 137         } else if (handleReadRequest(request, callback)) {
 138             // No-op
 139         } else if (request instanceof TransactionPurgeRequest) {
 140             enqueuePurge(callback, enqueuedTicks);
 141         } else if (request instanceof IncrementTransactionSequenceRequest) {
 142             // Local transactions do not have non-replayable requests which would be visible to the backend,
 143             // hence we can skip sequence increments.
 144             LOG.debug("Not replaying {}", request);
 145         } else {
 146             throw new IllegalArgumentException("Unhandled request " + request);
 147         }
 148     }
 149
 150     /**
 151      * Remote-to-local equivalent of {@link #handleReplayedRemoteRequest(TransactionRequest, Consumer, long)},
 152      * except it is invoked in the forwarding path from
 153      * {@link RemoteProxyTransaction#forwardToLocal(LocalProxyTransaction, TransactionRequest, Consumer)}.
 154      *
 155      * @param request Forwarded request
 156      * @param callback Callback to be invoked once the request completes
 157      */
 158     void handleForwardedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 159         if (request instanceof ModifyTransactionRequest) {
 160             applyForwardedModifyTransactionRequest((ModifyTransactionRequest) request, callback);
 161         } else if (handleReadRequest(request, callback)) {
 162             // No-op
 163         } else if (request instanceof TransactionPurgeRequest) {
 164             enqueuePurge(callback);
 165         } else {
 166             throw new IllegalArgumentException("Unhandled request " + request);
 167         }
 168     }
 169
 170     @Override
 171     final void forwardToRemote(final RemoteProxyTransaction successor, final TransactionRequest<?> request,
 172                          final Consumer<Response<?, ?>> callback) {
 173         if (request instanceof CommitLocalTransactionRequest) {
 174             final CommitLocalTransactionRequest req = (CommitLocalTransactionRequest) request;
 175             final DataTreeModification mod = req.getModification();
 176
 177             LOG.debug("Applying modification {} to successor {}", mod, successor);
 178             mod.applyToCursor(new AbstractDataTreeModificationCursor() {
 179                 @Override
 180                 public void write(final PathArgument child, final NormalizedNode<?, ?> data) {
 181                     successor.write(current().node(child), data);
 182                 }
 183
 184                 @Override
 185                 public void merge(final PathArgument child, final NormalizedNode<?, ?> data) {
 186                     successor.merge(current().node(child), data);
 187                 }
 188
 189                 @Override
 190                 public void delete(final PathArgument child) {
 191                     successor.delete(current().node(child));
 192                 }
 193             });
 194
 195             successor.sealOnly();
 196             final ModifyTransactionRequest successorReq = successor.commitRequest(req.isCoordinated());
 197             successor.sendRequest(successorReq, callback);
 198         } else if (request instanceof AbortLocalTransactionRequest) {
 199             LOG.debug("Forwarding abort {} to successor {}", request, successor);
 200             successor.abort();
 201         } else if (request instanceof TransactionPurgeRequest) {
 202             LOG.debug("Forwarding purge {} to successor {}", request, successor);
 203             successor.enqueuePurge(callback);
 204         } else if (request instanceof ModifyTransactionRequest) {
 205             successor.handleForwardedRequest(request, callback);
 206         } else {
 207             throwUnhandledRequest(request);
 208         }
 209     }
 210
 211     @Override
 212     void forwardToLocal(final LocalProxyTransaction successor, final TransactionRequest<?> request,
 213             final Consumer<Response<?, ?>> callback) {
 214         if (request instanceof AbortLocalTransactionRequest) {
 215             successor.sendAbort(request, callback);
 216         } else if (request instanceof TransactionPurgeRequest) {
 217             successor.enqueuePurge(callback);
 218         } else {
 219             throwUnhandledRequest(request);
 220         }
 221
 222         LOG.debug("Forwarded request {} to successor {}", request, successor);
 223     }
 224
 225     private static void throwUnhandledRequest(final TransactionRequest<?> request) {
 226         throw new IllegalArgumentException("Unhandled request" + request);
 227     }
 228
 229     void sendAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 230         sendRequest(request, callback);
 231     }
 232
 233     void enqueueAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback,
 234             final long enqueuedTicks) {
 235         enqueueRequest(request, callback, enqueuedTicks);
 236     }
 237 }