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