apps/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.client.mdsal.api.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     @GuardedBy("queuedTxOperations")
  44     private final List<Consumer<ProxyTransactionFacade>> queuedTxOperations = new ArrayList<>();
  45     private final SettableFuture<CommitInfo> settableFuture = SettableFuture.create();
  46     private final @NonNull FluentFuture<CommitInfo> completionFuture = FluentFuture.from(settableFuture);
  47     private final AtomicBoolean opened = new AtomicBoolean(true);
  48     private final RemoteDeviceId id;
  49
  50     private volatile ProxyTransactionFacade transactionFacade;
  51
  52     public ProxyReadWriteTransaction(final RemoteDeviceId id, final Future<Object> masterTxActorFuture,
  53             final ExecutionContext executionContext, final Timeout askTimeout) {
  54         this.id = id;
  55
  56         masterTxActorFuture.onComplete(new OnComplete<>() {
  57             @Override
  58             public void onComplete(final Throwable failure, final Object masterTxActor) {
  59                 final ProxyTransactionFacade newTransactionFacade;
  60                 if (failure != null) {
  61                     LOG.debug("{}: Failed to obtain master actor", id, failure);
  62                     newTransactionFacade = new FailedProxyTransactionFacade(id, failure);
  63                 } else {
  64                     LOG.debug("{}: Obtained master actor {}", id, masterTxActor);
  65                     newTransactionFacade = new ActorProxyTransactionFacade((ActorRef)masterTxActor, id,
  66                             executionContext, askTimeout);
  67                 }
  68
  69                 executePriorTransactionOperations(newTransactionFacade);
  70             }
  71         }, executionContext);
  72     }
  73
  74     @Override
  75     public FluentFuture<?> completionFuture() {
  76         return completionFuture;
  77     }
  78
  79     @Override
  80     public boolean cancel() {
  81         if (!opened.compareAndSet(true, false)) {
  82             return false;
  83         }
  84
  85         processTransactionOperation(DOMDataTreeWriteTransaction::cancel);
  86         return true;
  87     }
  88
  89     @Override
  90     public FluentFuture<Optional<NormalizedNode>> read(final LogicalDatastoreType store,
  91             final YangInstanceIdentifier path) {
  92         LOG.debug("{}: Read {} {}", id, store, path);
  93
  94         final SettableFuture<Optional<NormalizedNode>> returnFuture = SettableFuture.create();
  95         processTransactionOperation(facade -> returnFuture.setFuture(facade.read(store, path)));
  96         return FluentFuture.from(returnFuture);
  97     }
  98
  99     @Override
 100     public FluentFuture<Boolean> exists(final LogicalDatastoreType store,
 101             final YangInstanceIdentifier path) {
 102         LOG.debug("{}: Exists {} {}", id, store, path);
 103
 104         final SettableFuture<Boolean> returnFuture = SettableFuture.create();
 105         processTransactionOperation(facade -> returnFuture.setFuture(facade.exists(store, path)));
 106         return FluentFuture.from(returnFuture);
 107     }
 108
 109     @Override
 110     public void delete(final LogicalDatastoreType store, final YangInstanceIdentifier path) {
 111         checkOpen();
 112         LOG.debug("{}: Delete {} {}", id, store, path);
 113         processTransactionOperation(facade -> facade.delete(store, path));
 114     }
 115
 116     @Override
 117     public void put(final LogicalDatastoreType store, final YangInstanceIdentifier path, 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, 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 FluentFuture<CommitInfo> commit() {
 132         Preconditions.checkState(opened.compareAndSet(true, false), "%s: Transaction is already closed", id);
 133         LOG.debug("{}: Commit", id);
 134
 135         processTransactionOperation(facade -> settableFuture.setFuture(facade.commit()));
 136         return completionFuture;
 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 }