opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/ShardTransaction.java

   1 /*
   2  * Copyright (c) 2014 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
   9 package org.opendaylight.controller.cluster.datastore;
  10
  11 import akka.actor.ActorRef;
  12 import akka.actor.PoisonPill;
  13 import akka.actor.Props;
  14 import akka.actor.UntypedActor;
  15 import akka.event.Logging;
  16 import akka.event.LoggingAdapter;
  17 import akka.japi.Creator;
  18 import com.google.common.base.Optional;
  19 import com.google.common.util.concurrent.ListenableFuture;
  20 import org.opendaylight.controller.cluster.datastore.messages.CloseTransaction;
  21 import org.opendaylight.controller.cluster.datastore.messages.CloseTransactionReply;
  22 import org.opendaylight.controller.cluster.datastore.messages.DeleteData;
  23 import org.opendaylight.controller.cluster.datastore.messages.DeleteDataReply;
  24 import org.opendaylight.controller.cluster.datastore.messages.MergeData;
  25 import org.opendaylight.controller.cluster.datastore.messages.MergeDataReply;
  26 import org.opendaylight.controller.cluster.datastore.messages.ReadData;
  27 import org.opendaylight.controller.cluster.datastore.messages.ReadDataReply;
  28 import org.opendaylight.controller.cluster.datastore.messages.ReadyTransaction;
  29 import org.opendaylight.controller.cluster.datastore.messages.ReadyTransactionReply;
  30 import org.opendaylight.controller.cluster.datastore.messages.WriteData;
  31 import org.opendaylight.controller.cluster.datastore.messages.WriteDataReply;
  32 import org.opendaylight.controller.cluster.datastore.modification.CompositeModification;
  33 import org.opendaylight.controller.cluster.datastore.modification.DeleteModification;
  34 import org.opendaylight.controller.cluster.datastore.modification.ImmutableCompositeModification;
  35 import org.opendaylight.controller.cluster.datastore.modification.MergeModification;
  36 import org.opendaylight.controller.cluster.datastore.modification.MutableCompositeModification;
  37 import org.opendaylight.controller.cluster.datastore.modification.WriteModification;
  38 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  39 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  40 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain;
  41 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
  42 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  43
  44 import java.util.concurrent.ExecutionException;
  45
  46 /**
  47  * The ShardTransaction Actor represents a remote transaction
  48  * <p>
  49  * The ShardTransaction Actor delegates all actions to DOMDataReadWriteTransaction
  50  * </p>
  51  * <p>
  52  * Even though the DOMStore and the DOMStoreTransactionChain implement multiple types of transactions
  53  * the ShardTransaction Actor only works with read-write transactions. This is just to keep the logic simple. At this
  54  * time there are no known advantages for creating a read-only or write-only transaction which may change over time
  55  * at which point we can optimize things in the distributed store as well.
  56  * </p>
  57  * <p>
  58  * Handles Messages <br/>
  59  * ---------------- <br/>
  60  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.ReadData}
  61  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.WriteData}
  62  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.MergeData}
  63  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.DeleteData}
  64  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.ReadyTransaction}
  65  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.CloseTransaction}
  66  * </p>
  67  */
  68 public class ShardTransaction extends UntypedActor {
  69
  70     private final ActorRef shardActor;
  71
  72     // FIXME : see below
  73     // If transactionChain is not null then this transaction is part of a
  74     // transactionChain. Not really clear as to what that buys us
  75     private final DOMStoreTransactionChain transactionChain;
  76
  77     private final DOMStoreReadWriteTransaction transaction;
  78
  79     private final MutableCompositeModification modification =
  80         new MutableCompositeModification();
  81
  82     private final LoggingAdapter log =
  83         Logging.getLogger(getContext().system(), this);
  84
  85     public ShardTransaction(DOMStoreReadWriteTransaction transaction,
  86         ActorRef shardActor) {
  87         this(null, transaction, shardActor);
  88     }
  89
  90     public ShardTransaction(DOMStoreTransactionChain transactionChain, DOMStoreReadWriteTransaction transaction,
  91         ActorRef shardActor) {
  92         this.transactionChain = transactionChain;
  93         this.transaction = transaction;
  94         this.shardActor = shardActor;
  95     }
  96
  97
  98
  99     public static Props props(final DOMStoreReadWriteTransaction transaction,
 100         final ActorRef shardActor) {
 101         return Props.create(new Creator<ShardTransaction>() {
 102
 103             @Override
 104             public ShardTransaction create() throws Exception {
 105                 return new ShardTransaction(transaction, shardActor);
 106             }
 107         });
 108     }
 109
 110     public static Props props(final DOMStoreTransactionChain transactionChain, final DOMStoreReadWriteTransaction transaction,
 111         final ActorRef shardActor) {
 112         return Props.create(new Creator<ShardTransaction>() {
 113
 114             @Override
 115             public ShardTransaction create() throws Exception {
 116                 return new ShardTransaction(transactionChain, transaction, shardActor);
 117             }
 118         });
 119     }
 120
 121
 122     @Override
 123     public void onReceive(Object message) throws Exception {
 124         log.debug("Received message {}", message);
 125
 126         if (message instanceof ReadData) {
 127             readData((ReadData) message);
 128         } else if (message instanceof WriteData) {
 129             writeData((WriteData) message);
 130         } else if (message instanceof MergeData) {
 131             mergeData((MergeData) message);
 132         } else if (message instanceof DeleteData) {
 133             deleteData((DeleteData) message);
 134         } else if (message instanceof ReadyTransaction) {
 135             readyTransaction((ReadyTransaction) message);
 136         } else if (message instanceof CloseTransaction) {
 137             closeTransaction((CloseTransaction) message);
 138         } else if (message instanceof GetCompositedModification) {
 139             // This is here for testing only
 140             getSender().tell(new GetCompositeModificationReply(
 141                 new ImmutableCompositeModification(modification)), getSelf());
 142         }
 143     }
 144
 145     private void readData(ReadData message) {
 146         final ActorRef sender = getSender();
 147         final ActorRef self = getSelf();
 148         final InstanceIdentifier path = message.getPath();
 149         final ListenableFuture<Optional<NormalizedNode<?, ?>>> future =
 150             transaction.read(path);
 151
 152         future.addListener(new Runnable() {
 153             @Override
 154             public void run() {
 155                 try {
 156                     Optional<NormalizedNode<?, ?>> optional = future.get();
 157                     if (optional.isPresent()) {
 158                         sender.tell(new ReadDataReply(optional.get()), self);
 159                     } else {
 160                         sender.tell(new ReadDataReply(null), self);
 161                     }
 162                 } catch (InterruptedException | ExecutionException e) {
 163                     log.error(e,
 164                         "An exception happened when reading data from path : "
 165                             + path.toString());
 166                 }
 167
 168             }
 169         }, getContext().dispatcher());
 170     }
 171
 172
 173     private void writeData(WriteData message) {
 174         modification.addModification(
 175             new WriteModification(message.getPath(), message.getData()));
 176         transaction.write(message.getPath(), message.getData());
 177         getSender().tell(new WriteDataReply(), getSelf());
 178     }
 179
 180     private void mergeData(MergeData message) {
 181         modification.addModification(
 182             new MergeModification(message.getPath(), message.getData()));
 183         transaction.merge(message.getPath(), message.getData());
 184         getSender().tell(new MergeDataReply(), getSelf());
 185     }
 186
 187     private void deleteData(DeleteData message) {
 188         modification.addModification(new DeleteModification(message.getPath()));
 189         transaction.delete(message.getPath());
 190         getSender().tell(new DeleteDataReply(), getSelf());
 191     }
 192
 193     private void readyTransaction(ReadyTransaction message) {
 194         DOMStoreThreePhaseCommitCohort cohort = transaction.ready();
 195         ActorRef cohortActor = getContext().actorOf(
 196             ThreePhaseCommitCohort.props(cohort, shardActor, modification));
 197         getSender()
 198             .tell(new ReadyTransactionReply(cohortActor.path()), getSelf());
 199
 200     }
 201
 202     private void closeTransaction(CloseTransaction message) {
 203         transaction.close();
 204         getSender().tell(new CloseTransactionReply(), getSelf());
 205         getSelf().tell(PoisonPill.getInstance(), getSelf());
 206     }
 207
 208
 209     // These classes are in here for test purposes only
 210
 211
 212     static class GetCompositedModification {
 213
 214     }
 215
 216
 217     static class GetCompositeModificationReply {
 218         private final CompositeModification modification;
 219
 220
 221         GetCompositeModificationReply(CompositeModification modification) {
 222             this.modification = modification;
 223         }
 224
 225
 226         public CompositeModification getModification() {
 227             return modification;
 228         }
 229     }
 230 }