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.immediateBooleanFluentFuture(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             if (callback != null) {
 108                 final YangInstanceIdentifier path = ((ReadTransactionRequest) request).getPath();
 109                 final Optional<NormalizedNode> result = readOnlyView().readNode(path);
 110                 executeInActor(() -> callback.accept(new ReadTransactionSuccess(request.getTarget(),
 111                     request.getSequence(), result)));
 112             }
 113             return true;
 114         } else if (request instanceof ExistsTransactionRequest) {
 115             if (callback != null) {
 116                 final YangInstanceIdentifier path = ((ExistsTransactionRequest) request).getPath();
 117                 final boolean result = readOnlyView().readNode(path).isPresent();
 118                 executeInActor(() -> callback.accept(new ExistsTransactionSuccess(request.getTarget(),
 119                     request.getSequence(), result)));
 120             }
 121             return true;
 122         } else {
 123             return false;
 124         }
 125     }
 126
 127     @Override
 128     void handleReplayedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback,
 129             final long enqueuedTicks) {
 130         if (request instanceof ModifyTransactionRequest) {
 131             replayModifyTransactionRequest((ModifyTransactionRequest) request, callback, enqueuedTicks);
 132         } else if (handleReadRequest(request, callback)) {
 133             // No-op
 134         } else if (request instanceof TransactionPurgeRequest) {
 135             enqueuePurge(callback, enqueuedTicks);
 136         } else if (request instanceof IncrementTransactionSequenceRequest) {
 137             // Local transactions do not have non-replayable requests which would be visible to the backend,
 138             // hence we can skip sequence increments.
 139             LOG.debug("Not replaying {}", request);
 140         } else {
 141             throw new IllegalArgumentException("Unhandled request " + request);
 142         }
 143     }
 144
 145     /**
 146      * Remote-to-local equivalent of {@link #handleReplayedRemoteRequest(TransactionRequest, Consumer, long)},
 147      * except it is invoked in the forwarding path from
 148      * {@link RemoteProxyTransaction#forwardToLocal(LocalProxyTransaction, TransactionRequest, Consumer)}.
 149      *
 150      * @param request Forwarded request
 151      * @param callback Callback to be invoked once the request completes
 152      */
 153     void handleForwardedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 154         if (request instanceof ModifyTransactionRequest) {
 155             applyForwardedModifyTransactionRequest((ModifyTransactionRequest) request, callback);
 156         } else if (handleReadRequest(request, callback)) {
 157             // No-op
 158         } else if (request instanceof TransactionPurgeRequest) {
 159             enqueuePurge(callback);
 160         } else {
 161             throw new IllegalArgumentException("Unhandled request " + request);
 162         }
 163     }
 164
 165     @Override
 166     final void forwardToRemote(final RemoteProxyTransaction successor, final TransactionRequest<?> request,
 167                          final Consumer<Response<?, ?>> callback) {
 168         if (request instanceof CommitLocalTransactionRequest) {
 169             final CommitLocalTransactionRequest req = (CommitLocalTransactionRequest) request;
 170             final DataTreeModification mod = req.getModification();
 171
 172             LOG.debug("Applying modification {} to successor {}", mod, successor);
 173             mod.applyToCursor(new AbstractDataTreeModificationCursor() {
 174                 @Override
 175                 public void write(final PathArgument child, final NormalizedNode data) {
 176                     successor.write(current().node(child), data);
 177                 }
 178
 179                 @Override
 180                 public void merge(final PathArgument child, final NormalizedNode data) {
 181                     successor.merge(current().node(child), data);
 182                 }
 183
 184                 @Override
 185                 public void delete(final PathArgument child) {
 186                     successor.delete(current().node(child));
 187                 }
 188             });
 189
 190             successor.sealOnly();
 191             final ModifyTransactionRequest successorReq = successor.commitRequest(req.isCoordinated());
 192             successor.sendRequest(successorReq, callback);
 193         } else if (request instanceof AbortLocalTransactionRequest) {
 194             LOG.debug("Forwarding abort {} to successor {}", request, successor);
 195             successor.abort();
 196         } else if (request instanceof TransactionPurgeRequest) {
 197             LOG.debug("Forwarding purge {} to successor {}", request, successor);
 198             successor.enqueuePurge(callback);
 199         } else if (request instanceof ModifyTransactionRequest) {
 200             successor.handleForwardedRequest(request, callback);
 201         } else {
 202             throwUnhandledRequest(request);
 203         }
 204     }
 205
 206     @Override
 207     void forwardToLocal(final LocalProxyTransaction successor, final TransactionRequest<?> request,
 208             final Consumer<Response<?, ?>> callback) {
 209         if (request instanceof AbortLocalTransactionRequest) {
 210             successor.sendAbort(request, callback);
 211         } else if (request instanceof TransactionPurgeRequest) {
 212             successor.enqueuePurge(callback);
 213         } else {
 214             throwUnhandledRequest(request);
 215         }
 216
 217         LOG.debug("Forwarded request {} to successor {}", request, successor);
 218     }
 219
 220     private static void throwUnhandledRequest(final TransactionRequest<?> request) {
 221         throw new IllegalArgumentException("Unhandled request " + request);
 222     }
 223
 224     void sendAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 225         sendRequest(request, callback);
 226     }
 227
 228     void enqueueAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback,
 229             final long enqueuedTicks) {
 230         enqueueRequest(request, callback, enqueuedTicks);
 231     }
 232 }