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