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