netconf/netconf-topology-singleton/src/main/java/org/opendaylight/netconf/topology/singleton/impl/tx/ProxyReadWriteTransaction.java

   1 /*
   2  * Copyright (c) 2017 Pantheon Technologies s.r.o. 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.netconf.topology.singleton.impl.tx;
  10
  11 import akka.actor.ActorRef;
  12 import akka.dispatch.OnComplete;
  13 import akka.util.Timeout;
  14 import com.google.common.base.Optional;
  15 import com.google.common.base.Preconditions;
  16 import com.google.common.util.concurrent.CheckedFuture;
  17 import com.google.common.util.concurrent.FluentFuture;
  18 import com.google.common.util.concurrent.SettableFuture;
  19 import java.util.ArrayList;
  20 import java.util.Collection;
  21 import java.util.List;
  22 import java.util.concurrent.atomic.AtomicBoolean;
  23 import java.util.function.Consumer;
  24 import javax.annotation.concurrent.GuardedBy;
  25 import org.eclipse.jdt.annotation.NonNull;
  26 import org.opendaylight.controller.md.sal.common.api.data.AsyncWriteTransaction;
  27 import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
  28 import org.opendaylight.controller.md.sal.common.api.data.ReadFailedException;
  29 import org.opendaylight.controller.md.sal.dom.api.DOMDataReadWriteTransaction;
  30 import org.opendaylight.mdsal.common.api.CommitInfo;
  31 import org.opendaylight.mdsal.common.api.MappingCheckedFuture;
  32 import org.opendaylight.netconf.sal.connect.util.RemoteDeviceId;
  33 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  34 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  35 import org.slf4j.Logger;
  36 import org.slf4j.LoggerFactory;
  37 import scala.concurrent.ExecutionContext;
  38 import scala.concurrent.Future;
  39
  40 /**
  41  * ProxyReadWriteTransaction uses provided {@link ActorRef} to delegate method calls to master
  42  * {@link org.opendaylight.netconf.topology.singleton.impl.actors.ReadWriteTransactionActor}.
  43  */
  44 public class ProxyReadWriteTransaction implements DOMDataReadWriteTransaction {
  45     private static final Logger LOG = LoggerFactory.getLogger(ProxyReadWriteTransaction.class);
  46
  47     private final RemoteDeviceId id;
  48     private final AtomicBoolean opened = new AtomicBoolean(true);
  49
  50     @GuardedBy("queuedTxOperations")
  51     private final List<Consumer<ProxyTransactionFacade>> queuedTxOperations = new ArrayList<>();
  52
  53     private volatile ProxyTransactionFacade transactionFacade;
  54
  55     public ProxyReadWriteTransaction(final RemoteDeviceId id, final Future<Object> masterTxActorFuture,
  56             final ExecutionContext executionContext, final Timeout askTimeout) {
  57         this.id = id;
  58
  59         masterTxActorFuture.onComplete(new OnComplete<Object>() {
  60             @Override
  61             public void onComplete(final Throwable failure, final Object masterTxActor) {
  62                 final ProxyTransactionFacade newTransactionFacade;
  63                 if (failure != null) {
  64                     LOG.debug("{}: Failed to obtain master actor", id, failure);
  65                     newTransactionFacade = new FailedProxyTransactionFacade(id, failure);
  66                 } else {
  67                     LOG.debug("{}: Obtained master actor {}", id, masterTxActor);
  68                     newTransactionFacade = new ActorProxyTransactionFacade((ActorRef)masterTxActor, id,
  69                             executionContext, askTimeout);
  70                 }
  71
  72                 executePriorTransactionOperations(newTransactionFacade);
  73             }
  74         }, executionContext);
  75     }
  76
  77     @Override
  78     public boolean cancel() {
  79         if (!opened.compareAndSet(true, false)) {
  80             return false;
  81         }
  82
  83         processTransactionOperation(AsyncWriteTransaction::cancel);
  84         return true;
  85     }
  86
  87     @Override
  88     public CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> read(final LogicalDatastoreType store,
  89             final YangInstanceIdentifier path) {
  90         LOG.debug("{}: Read {} {}", id, store, path);
  91
  92         final SettableFuture<Optional<NormalizedNode<?, ?>>> returnFuture = SettableFuture.create();
  93         processTransactionOperation(facade -> returnFuture.setFuture(facade.read(store, path)));
  94         return MappingCheckedFuture.create(returnFuture, ReadFailedException.MAPPER);
  95     }
  96
  97     @Override
  98     public CheckedFuture<Boolean, ReadFailedException> exists(final LogicalDatastoreType store,
  99             final YangInstanceIdentifier path) {
 100         LOG.debug("{}: Exists {} {}", id, store, path);
 101
 102         final SettableFuture<Boolean> returnFuture = SettableFuture.create();
 103         processTransactionOperation(facade -> returnFuture.setFuture(facade.exists(store, path)));
 104         return MappingCheckedFuture.create(returnFuture, ReadFailedException.MAPPER);
 105     }
 106
 107     @Override
 108     public void delete(final LogicalDatastoreType store, final YangInstanceIdentifier path) {
 109         checkOpen();
 110         LOG.debug("{}: Delete {} {}", id, store, path);
 111         processTransactionOperation(facade -> facade.delete(store, path));
 112     }
 113
 114     @Override
 115     public void put(final LogicalDatastoreType store, final YangInstanceIdentifier path,
 116                     final NormalizedNode<?, ?> data) {
 117         checkOpen();
 118         LOG.debug("{}: Put {} {}", id, store, path);
 119         processTransactionOperation(facade -> facade.put(store, path, data));
 120     }
 121
 122     @Override
 123     public void merge(final LogicalDatastoreType store, final YangInstanceIdentifier path,
 124                       final NormalizedNode<?, ?> data) {
 125         checkOpen();
 126         LOG.debug("{}: Merge {} {}", id, store, path);
 127         processTransactionOperation(facade -> facade.merge(store, path, data));
 128     }
 129
 130     @Override
 131     public @NonNull FluentFuture<? extends @NonNull CommitInfo> commit() {
 132         Preconditions.checkState(opened.compareAndSet(true, false), "%s: Transaction is already closed", id);
 133         LOG.debug("{}: Commit", id);
 134
 135         final SettableFuture<CommitInfo> returnFuture = SettableFuture.create();
 136         processTransactionOperation(facade -> returnFuture.setFuture(facade.commit()));
 137         return returnFuture;
 138     }
 139
 140     @Override
 141     public Object getIdentifier() {
 142         return id;
 143     }
 144
 145     private void processTransactionOperation(final Consumer<ProxyTransactionFacade> operation) {
 146         final ProxyTransactionFacade facadeOnEntry;
 147         synchronized (queuedTxOperations) {
 148             if (transactionFacade == null) {
 149                 LOG.debug("{}: Queuing transaction operation", id);
 150
 151                 queuedTxOperations.add(operation);
 152                 facadeOnEntry = null;
 153             }  else {
 154                 facadeOnEntry = transactionFacade;
 155             }
 156         }
 157
 158         if (facadeOnEntry != null) {
 159             operation.accept(facadeOnEntry);
 160         }
 161     }
 162
 163     private void executePriorTransactionOperations(final ProxyTransactionFacade newTransactionFacade) {
 164         while (true) {
 165             // Access to queuedTxOperations and transactionFacade must be protected and atomic
 166             // (ie synchronized) with respect to #processTransactionOperation to handle timing
 167             // issues and ensure no ProxyTransactionFacade is missed and that they are processed
 168             // in the order they occurred.
 169
 170             // We'll make a local copy of the queuedTxOperations list to handle re-entrancy
 171             // in case a transaction operation results in another transaction operation being
 172             // queued (eg a put operation from a client read Future callback that is notified
 173             // synchronously).
 174             final Collection<Consumer<ProxyTransactionFacade>> operationsBatch;
 175             synchronized (queuedTxOperations) {
 176                 if (queuedTxOperations.isEmpty()) {
 177                     // We're done invoking the transaction operations so we can now publish the
 178                     // ProxyTransactionFacade.
 179                     transactionFacade = newTransactionFacade;
 180                     break;
 181                 }
 182
 183                 operationsBatch = new ArrayList<>(queuedTxOperations);
 184                 queuedTxOperations.clear();
 185             }
 186
 187             // Invoke transaction operations outside the sync block to avoid unnecessary blocking.
 188             for (Consumer<ProxyTransactionFacade> oper : operationsBatch) {
 189                 oper.accept(newTransactionFacade);
 190             }
 191         }
 192     }
 193
 194     private void checkOpen() {
 195         Preconditions.checkState(opened.get(), "%s: Transaction is closed", id);
 196     }
 197 }