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()), response -> {
  92             LOG.debug("Transaction {} abort completed with {}", identifier, response);
  93         });
  94     }
  95
  96     @Override
  97     void handleReplayedLocalRequest(final AbstractLocalTransactionRequest<?> request,
  98             final Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
  99         if (request instanceof AbortLocalTransactionRequest) {
 100             enqueueAbort(request, callback, enqueuedTicks);
 101         } else {
 102             throw new IllegalArgumentException("Unhandled request" + request);
 103         }
 104     }
 105
 106     private boolean handleReadRequest(final TransactionRequest<?> request,
 107             final @Nullable Consumer<Response<?, ?>> callback) {
 108         // Note we delay completion of read requests to limit the scope at which the client can run, as they have
 109         // listeners, which we do not want to execute while we are reconnecting.
 110         if (request instanceof ReadTransactionRequest) {
 111             final YangInstanceIdentifier path = ((ReadTransactionRequest) request).getPath();
 112             final Optional<NormalizedNode<?, ?>> result = readOnlyView().readNode(path);
 113             if (callback != null) {
 114                 // XXX: FB does not see that callback is final, on stack and has be check for non-null.
 115                 final Consumer<Response<?, ?>> fbIsStupid = Preconditions.checkNotNull(callback);
 116                 executeInActor(() -> fbIsStupid.accept(new ReadTransactionSuccess(request.getTarget(),
 117                     request.getSequence(), result)));
 118             }
 119             return true;
 120         } else if (request instanceof ExistsTransactionRequest) {
 121             final YangInstanceIdentifier path = ((ExistsTransactionRequest) request).getPath();
 122             final boolean result = readOnlyView().readNode(path).isPresent();
 123             if (callback != null) {
 124                 // XXX: FB does not see that callback is final, on stack and has be check for non-null.
 125                 final Consumer<Response<?, ?>> fbIsStupid = Preconditions.checkNotNull(callback);
 126                 executeInActor(() -> fbIsStupid.accept(new ExistsTransactionSuccess(request.getTarget(),
 127                     request.getSequence(), result)));
 128             }
 129             return true;
 130         } else {
 131             return false;
 132         }
 133     }
 134
 135     @Override
 136     void handleReplayedRemoteRequest(final TransactionRequest<?> request,
 137             final @Nullable Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
 138         if (request instanceof ModifyTransactionRequest) {
 139             replayModifyTransactionRequest((ModifyTransactionRequest) request, callback, enqueuedTicks);
 140         } else if (handleReadRequest(request, callback)) {
 141             // No-op
 142         } else if (request instanceof TransactionPurgeRequest) {
 143             enqueuePurge(enqueuedTicks);
 144         } else if (request instanceof IncrementTransactionSequenceRequest) {
 145             // Local transactions do not have non-replayable requests which would be visible to the backend,
 146             // hence we can skip sequence increments.
 147             LOG.debug("Not replaying {}", request);
 148         } else {
 149             throw new IllegalArgumentException("Unhandled request " + request);
 150         }
 151     }
 152
 153     /**
 154      * Remote-to-local equivalent of {@link #handleReplayedRemoteRequest(TransactionRequest, Consumer, long)},
 155      * except it is invoked in the forwarding path from
 156      * {@link RemoteProxyTransaction#forwardToLocal(LocalProxyTransaction, TransactionRequest, Consumer)}.
 157      *
 158      * @param request Forwarded request
 159      * @param callback Callback to be invoked once the request completes
 160      */
 161     void handleForwardedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 162         if (request instanceof ModifyTransactionRequest) {
 163             applyModifyTransactionRequest((ModifyTransactionRequest) request, callback);
 164         } else if (handleReadRequest(request, callback)) {
 165             // No-op
 166         } else if (request instanceof TransactionPurgeRequest) {
 167             sendPurge();
 168         } else {
 169             throw new IllegalArgumentException("Unhandled request " + request);
 170         }
 171     }
 172
 173     @Override
 174     final void forwardToRemote(final RemoteProxyTransaction successor, final TransactionRequest<?> request,
 175                          final Consumer<Response<?, ?>> callback) {
 176         if (request instanceof CommitLocalTransactionRequest) {
 177             final CommitLocalTransactionRequest req = (CommitLocalTransactionRequest) request;
 178             final DataTreeModification mod = req.getModification();
 179
 180             LOG.debug("Applying modification {} to successor {}", mod, successor);
 181             mod.applyToCursor(new AbstractDataTreeModificationCursor() {
 182                 @Override
 183                 public void write(final PathArgument child, final NormalizedNode<?, ?> data) {
 184                     successor.write(current().node(child), data);
 185                 }
 186
 187                 @Override
 188                 public void merge(final PathArgument child, final NormalizedNode<?, ?> data) {
 189                     successor.merge(current().node(child), data);
 190                 }
 191
 192                 @Override
 193                 public void delete(final PathArgument child) {
 194                     successor.delete(current().node(child));
 195                 }
 196             });
 197
 198             successor.ensureSealed();
 199
 200             final ModifyTransactionRequest successorReq = successor.commitRequest(req.isCoordinated());
 201             successor.sendRequest(successorReq, callback);
 202         } else if (request instanceof AbortLocalTransactionRequest) {
 203             LOG.debug("Forwarding abort {} to successor {}", request, successor);
 204             successor.abort();
 205         } else if (request instanceof TransactionPurgeRequest) {
 206             LOG.debug("Forwarding purge {} to successor {}", request, successor);
 207             successor.sendPurge();
 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.sendPurge();
 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 }