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 package org.opendaylight.netconf.topology.singleton.impl.tx;
   9
  10 import akka.actor.ActorRef;
  11 import akka.dispatch.OnComplete;
  12 import akka.util.Timeout;
  13 import com.google.common.base.Preconditions;
  14 import com.google.common.util.concurrent.FluentFuture;
  15 import com.google.common.util.concurrent.SettableFuture;
  16 import java.util.ArrayList;
  17 import java.util.Collection;
  18 import java.util.List;
  19 import java.util.Optional;
  20 import java.util.concurrent.atomic.AtomicBoolean;
  21 import java.util.function.Consumer;
  22 import org.checkerframework.checker.lock.qual.GuardedBy;
  23 import org.eclipse.jdt.annotation.NonNull;
  24 import org.opendaylight.mdsal.common.api.CommitInfo;
  25 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
  26 import org.opendaylight.mdsal.dom.api.DOMDataTreeReadWriteTransaction;
  27 import org.opendaylight.mdsal.dom.api.DOMDataTreeWriteTransaction;
  28 import org.opendaylight.netconf.sal.connect.util.RemoteDeviceId;
  29 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  30 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  31 import org.slf4j.Logger;
  32 import org.slf4j.LoggerFactory;
  33 import scala.concurrent.ExecutionContext;
  34 import scala.concurrent.Future;
  35
  36 /**
  37  * ProxyReadWriteTransaction uses provided {@link ActorRef} to delegate method calls to master
  38  * {@link org.opendaylight.netconf.topology.singleton.impl.actors.ReadWriteTransactionActor}.
  39  */
  40 public class ProxyReadWriteTransaction implements DOMDataTreeReadWriteTransaction {
  41     private static final Logger LOG = LoggerFactory.getLogger(ProxyReadWriteTransaction.class);
  42
  43     private final RemoteDeviceId id;
  44     private final AtomicBoolean opened = new AtomicBoolean(true);
  45
  46     @GuardedBy("queuedTxOperations")
  47     private final List<Consumer<ProxyTransactionFacade>> queuedTxOperations = new ArrayList<>();
  48
  49     private volatile ProxyTransactionFacade transactionFacade;
  50
  51     public ProxyReadWriteTransaction(final RemoteDeviceId id, final Future<Object> masterTxActorFuture,
  52             final ExecutionContext executionContext, final Timeout askTimeout) {
  53         this.id = id;
  54
  55         masterTxActorFuture.onComplete(new OnComplete<Object>() {
  56             @Override
  57             public void onComplete(final Throwable failure, final Object masterTxActor) {
  58                 final ProxyTransactionFacade newTransactionFacade;
  59                 if (failure != null) {
  60                     LOG.debug("{}: Failed to obtain master actor", id, failure);
  61                     newTransactionFacade = new FailedProxyTransactionFacade(id, failure);
  62                 } else {
  63                     LOG.debug("{}: Obtained master actor {}", id, masterTxActor);
  64                     newTransactionFacade = new ActorProxyTransactionFacade((ActorRef)masterTxActor, id,
  65                             executionContext, askTimeout);
  66                 }
  67
  68                 executePriorTransactionOperations(newTransactionFacade);
  69             }
  70         }, executionContext);
  71     }
  72
  73     @Override
  74     public boolean cancel() {
  75         if (!opened.compareAndSet(true, false)) {
  76             return false;
  77         }
  78
  79         processTransactionOperation(DOMDataTreeWriteTransaction::cancel);
  80         return true;
  81     }
  82
  83     @Override
  84     public void close() {
  85         cancel();
  86     }
  87
  88     @Override
  89     public FluentFuture<Optional<NormalizedNode<?, ?>>> read(final LogicalDatastoreType store,
  90             final YangInstanceIdentifier path) {
  91         LOG.debug("{}: Read {} {}", id, store, path);
  92
  93         final SettableFuture<Optional<NormalizedNode<?, ?>>> returnFuture = SettableFuture.create();
  94         processTransactionOperation(facade -> returnFuture.setFuture(facade.read(store, path)));
  95         return FluentFuture.from(returnFuture);
  96     }
  97
  98     @Override
  99     public FluentFuture<Boolean> exists(final LogicalDatastoreType store,
 100             final YangInstanceIdentifier path) {
 101         LOG.debug("{}: Exists {} {}", id, store, path);
 102
 103         final SettableFuture<Boolean> returnFuture = SettableFuture.create();
 104         processTransactionOperation(facade -> returnFuture.setFuture(facade.exists(store, path)));
 105         return FluentFuture.from(returnFuture);
 106     }
 107
 108     @Override
 109     public void delete(final LogicalDatastoreType store, final YangInstanceIdentifier path) {
 110         checkOpen();
 111         LOG.debug("{}: Delete {} {}", id, store, path);
 112         processTransactionOperation(facade -> facade.delete(store, path));
 113     }
 114
 115     @Override
 116     public void put(final LogicalDatastoreType store, final YangInstanceIdentifier path,
 117                     final NormalizedNode<?, ?> data) {
 118         checkOpen();
 119         LOG.debug("{}: Put {} {}", id, store, path);
 120         processTransactionOperation(facade -> facade.put(store, path, data));
 121     }
 122
 123     @Override
 124     public void merge(final LogicalDatastoreType store, final YangInstanceIdentifier path,
 125                       final NormalizedNode<?, ?> data) {
 126         checkOpen();
 127         LOG.debug("{}: Merge {} {}", id, store, path);
 128         processTransactionOperation(facade -> facade.merge(store, path, data));
 129     }
 130
 131     @Override
 132     public @NonNull FluentFuture<? extends @NonNull CommitInfo> commit() {
 133         Preconditions.checkState(opened.compareAndSet(true, false), "%s: Transaction is already closed", id);
 134         LOG.debug("{}: Commit", id);
 135
 136         final SettableFuture<CommitInfo> returnFuture = SettableFuture.create();
 137         processTransactionOperation(facade -> returnFuture.setFuture(facade.commit()));
 138         return FluentFuture.from(returnFuture);
 139     }
 140
 141     @Override
 142     public Object getIdentifier() {
 143         return id;
 144     }
 145
 146     private void processTransactionOperation(final Consumer<ProxyTransactionFacade> operation) {
 147         final ProxyTransactionFacade facadeOnEntry;
 148         synchronized (queuedTxOperations) {
 149             if (transactionFacade == null) {
 150                 LOG.debug("{}: Queuing transaction operation", id);
 151
 152                 queuedTxOperations.add(operation);
 153                 facadeOnEntry = null;
 154             }  else {
 155                 facadeOnEntry = transactionFacade;
 156             }
 157         }
 158
 159         if (facadeOnEntry != null) {
 160             operation.accept(facadeOnEntry);
 161         }
 162     }
 163
 164     private void executePriorTransactionOperations(final ProxyTransactionFacade newTransactionFacade) {
 165         while (true) {
 166             // Access to queuedTxOperations and transactionFacade must be protected and atomic
 167             // (ie synchronized) with respect to #processTransactionOperation to handle timing
 168             // issues and ensure no ProxyTransactionFacade is missed and that they are processed
 169             // in the order they occurred.
 170
 171             // We'll make a local copy of the queuedTxOperations list to handle re-entrancy
 172             // in case a transaction operation results in another transaction operation being
 173             // queued (eg a put operation from a client read Future callback that is notified
 174             // synchronously).
 175             final Collection<Consumer<ProxyTransactionFacade>> operationsBatch;
 176             synchronized (queuedTxOperations) {
 177                 if (queuedTxOperations.isEmpty()) {
 178                     // We're done invoking the transaction operations so we can now publish the
 179                     // ProxyTransactionFacade.
 180                     transactionFacade = newTransactionFacade;
 181                     break;
 182                 }
 183
 184                 operationsBatch = new ArrayList<>(queuedTxOperations);
 185                 queuedTxOperations.clear();
 186             }
 187
 188             // Invoke transaction operations outside the sync block to avoid unnecessary blocking.
 189             for (Consumer<ProxyTransactionFacade> oper : operationsBatch) {
 190                 oper.accept(newTransactionFacade);
 191             }
 192         }
 193     }
 194
 195     private void checkOpen() {
 196         Preconditions.checkState(opened.get(), "%s: Transaction is closed", id);
 197     }
 198 }