opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/TransactionProxy.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.ActorPath;
  12 import akka.actor.ActorSelection;
  13 import com.google.common.base.Optional;
  14 import com.google.common.util.concurrent.ListenableFuture;
  15 import com.google.common.util.concurrent.ListenableFutureTask;
  16 import org.opendaylight.controller.cluster.datastore.messages.CloseTransaction;
  17 import org.opendaylight.controller.cluster.datastore.messages.CreateTransaction;
  18 import org.opendaylight.controller.cluster.datastore.messages.DeleteData;
  19 import org.opendaylight.controller.cluster.datastore.messages.MergeData;
  20 import org.opendaylight.controller.cluster.datastore.messages.ReadData;
  21 import org.opendaylight.controller.cluster.datastore.messages.ReadDataReply;
  22 import org.opendaylight.controller.cluster.datastore.messages.ReadyTransaction;
  23 import org.opendaylight.controller.cluster.datastore.messages.ReadyTransactionReply;
  24 import org.opendaylight.controller.cluster.datastore.messages.WriteData;
  25 import org.opendaylight.controller.cluster.datastore.utils.ActorContext;
  26 import org.opendaylight.controller.protobuff.messages.transaction.ShardTransactionMessages.CreateTransactionReply;
  27 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  28 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  29 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
  30 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  31 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  32
  33 import java.util.ArrayList;
  34 import java.util.HashMap;
  35 import java.util.List;
  36 import java.util.Map;
  37 import java.util.concurrent.Callable;
  38 import java.util.concurrent.ExecutorService;
  39 import java.util.concurrent.atomic.AtomicLong;
  40
  41 /**
  42  * TransactionProxy acts as a proxy for one or more transactions that were created on a remote shard
  43  * <p>
  44  * Creating a transaction on the consumer side will create one instance of a transaction proxy. If during
  45  * the transaction reads and writes are done on data that belongs to different shards then a separate transaction will
  46  * be created on each of those shards by the TransactionProxy
  47  *</p>
  48  * <p>
  49  * The TransactionProxy does not make any guarantees about atomicity or order in which the transactions on the various
  50  * shards will be executed.
  51  * </p>
  52  */
  53 public class TransactionProxy implements DOMStoreReadWriteTransaction {
  54     public enum TransactionType {
  55         READ_ONLY,
  56         WRITE_ONLY,
  57         READ_WRITE
  58     }
  59
  60     private static final AtomicLong counter = new AtomicLong();
  61
  62     private final TransactionType transactionType;
  63     private final ActorContext actorContext;
  64     private final Map<String, ActorSelection> remoteTransactionPaths = new HashMap<>();
  65     private final String identifier;
  66     private final ExecutorService executor;
  67     private final SchemaContext schemaContext;
  68
  69     public TransactionProxy(
  70         ActorContext actorContext,
  71         TransactionType transactionType,
  72         ExecutorService executor,
  73         SchemaContext schemaContext
  74         ) {
  75
  76         this.identifier = "txn-" + counter.getAndIncrement();
  77         this.transactionType = transactionType;
  78         this.actorContext = actorContext;
  79         this.executor = executor;
  80         this.schemaContext = schemaContext;
  81
  82         Object response = actorContext.executeShardOperation(Shard.DEFAULT_NAME, new CreateTransaction(identifier), ActorContext.ASK_DURATION);
  83         if(response instanceof CreateTransactionReply){
  84             CreateTransactionReply reply = (CreateTransactionReply) response;
  85             remoteTransactionPaths.put(Shard.DEFAULT_NAME, actorContext.actorSelection(reply.getTransactionActorPath()));
  86         }
  87     }
  88
  89     @Override
  90     public ListenableFuture<Optional<NormalizedNode<?, ?>>> read(final InstanceIdentifier path) {
  91         final ActorSelection remoteTransaction = remoteTransactionFromIdentifier(path);
  92
  93         Callable<Optional<NormalizedNode<?,?>>> call = new Callable() {
  94
  95             @Override public Optional<NormalizedNode<?,?>> call() throws Exception {
  96                 Object response = actorContext
  97                     .executeRemoteOperation(remoteTransaction, new ReadData(path).toSerializable(),
  98                         ActorContext.ASK_DURATION);
  99                 if(response.getClass().equals(ReadDataReply.SERIALIZABLE_CLASS)){
 100                     ReadDataReply reply = ReadDataReply.fromSerializable(schemaContext,path, response);
 101                     if(reply.getNormalizedNode() == null){
 102                         return Optional.absent();
 103                     }
 104                     //FIXME : A cast should not be required here ???
 105                     return (Optional<NormalizedNode<?, ?>>) Optional.of(reply.getNormalizedNode());
 106                 }
 107
 108                 return Optional.absent();
 109             }
 110         };
 111
 112         ListenableFutureTask<Optional<NormalizedNode<?, ?>>>
 113             future = ListenableFutureTask.create(call);
 114
 115         executor.submit(future);
 116
 117         return future;
 118     }
 119
 120     @Override
 121     public void write(InstanceIdentifier path, NormalizedNode<?, ?> data) {
 122         final ActorSelection remoteTransaction = remoteTransactionFromIdentifier(path);
 123         remoteTransaction.tell(new WriteData(path, data, schemaContext).toSerializable(), null);
 124     }
 125
 126     @Override
 127     public void merge(InstanceIdentifier path, NormalizedNode<?, ?> data) {
 128         final ActorSelection remoteTransaction = remoteTransactionFromIdentifier(path);
 129         remoteTransaction.tell(new MergeData(path, data, schemaContext).toSerializable(), null);
 130     }
 131
 132     @Override
 133     public void delete(InstanceIdentifier path) {
 134         final ActorSelection remoteTransaction = remoteTransactionFromIdentifier(path);
 135         remoteTransaction.tell(new DeleteData(path).toSerializable(), null);
 136     }
 137
 138     @Override
 139     public DOMStoreThreePhaseCommitCohort ready() {
 140         List<ActorPath> cohortPaths = new ArrayList<>();
 141
 142         for(ActorSelection remoteTransaction : remoteTransactionPaths.values()) {
 143             Object result = actorContext.executeRemoteOperation(remoteTransaction,
 144                 new ReadyTransaction(),
 145                 ActorContext.ASK_DURATION
 146             );
 147
 148             if(result instanceof ReadyTransactionReply){
 149                 ReadyTransactionReply reply = (ReadyTransactionReply) result;
 150                 cohortPaths.add(reply.getCohortPath());
 151             }
 152         }
 153
 154         return new ThreePhaseCommitCohortProxy(actorContext, cohortPaths, identifier, executor);
 155     }
 156
 157     @Override
 158     public Object getIdentifier() {
 159         return this.identifier;
 160     }
 161
 162     @Override
 163     public void close() {
 164         for(ActorSelection remoteTransaction : remoteTransactionPaths.values()) {
 165             remoteTransaction.tell(new CloseTransaction(), null);
 166         }
 167     }
 168
 169     private ActorSelection remoteTransactionFromIdentifier(InstanceIdentifier path){
 170         String shardName = shardNameFromIdentifier(path);
 171         return remoteTransactionPaths.get(shardName);
 172     }
 173
 174     private String shardNameFromIdentifier(InstanceIdentifier path){
 175         return Shard.DEFAULT_NAME;
 176     }
 177 }