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