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 edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
  17 import java.util.ArrayList;
  18 import java.util.Collection;
  19 import java.util.List;
  20 import java.util.Optional;
  21 import java.util.concurrent.atomic.AtomicBoolean;
  22 import java.util.function.Consumer;
  23 import org.checkerframework.checker.lock.qual.GuardedBy;
  24 import org.eclipse.jdt.annotation.NonNull;
  25 import org.opendaylight.mdsal.common.api.CommitInfo;
  26 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
  27 import org.opendaylight.mdsal.dom.api.DOMDataTreeReadWriteTransaction;
  28 import org.opendaylight.mdsal.dom.api.DOMDataTreeWriteTransaction;
  29 import org.opendaylight.netconf.sal.connect.util.RemoteDeviceId;
  30 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  31 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  32 import org.slf4j.Logger;
  33 import org.slf4j.LoggerFactory;
  34 import scala.concurrent.ExecutionContext;
  35 import scala.concurrent.Future;
  36
  37 /**
  38  * ProxyReadWriteTransaction uses provided {@link ActorRef} to delegate method calls to master
  39  * {@link org.opendaylight.netconf.topology.singleton.impl.actors.ReadWriteTransactionActor}.
  40  */
  41 public class ProxyReadWriteTransaction implements DOMDataTreeReadWriteTransaction {
  42     private static final Logger LOG = LoggerFactory.getLogger(ProxyReadWriteTransaction.class);
  43
  44     private final RemoteDeviceId id;
  45     private final AtomicBoolean opened = new AtomicBoolean(true);
  46
  47     @GuardedBy("queuedTxOperations")
  48     private final List<Consumer<ProxyTransactionFacade>> queuedTxOperations = new ArrayList<>();
  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 boolean cancel() {
  76         if (!opened.compareAndSet(true, false)) {
  77             return false;
  78         }
  79
  80         processTransactionOperation(DOMDataTreeWriteTransaction::cancel);
  81         return true;
  82     }
  83
  84     @Override
  85     public FluentFuture<Optional<NormalizedNode>> read(final LogicalDatastoreType store,
  86             final YangInstanceIdentifier path) {
  87         LOG.debug("{}: Read {} {}", id, store, path);
  88
  89         final SettableFuture<Optional<NormalizedNode>> returnFuture = SettableFuture.create();
  90         processTransactionOperation(facade -> returnFuture.setFuture(facade.read(store, path)));
  91         return FluentFuture.from(returnFuture);
  92     }
  93
  94     @Override
  95     public FluentFuture<Boolean> exists(final LogicalDatastoreType store,
  96             final YangInstanceIdentifier path) {
  97         LOG.debug("{}: Exists {} {}", id, store, path);
  98
  99         final SettableFuture<Boolean> returnFuture = SettableFuture.create();
 100         processTransactionOperation(facade -> returnFuture.setFuture(facade.exists(store, path)));
 101         return FluentFuture.from(returnFuture);
 102     }
 103
 104     @Override
 105     public void delete(final LogicalDatastoreType store, final YangInstanceIdentifier path) {
 106         checkOpen();
 107         LOG.debug("{}: Delete {} {}", id, store, path);
 108         processTransactionOperation(facade -> facade.delete(store, path));
 109     }
 110
 111     @Override
 112     public void put(final LogicalDatastoreType store, final YangInstanceIdentifier path, final NormalizedNode data) {
 113         checkOpen();
 114         LOG.debug("{}: Put {} {}", id, store, path);
 115         processTransactionOperation(facade -> facade.put(store, path, data));
 116     }
 117
 118     @Override
 119     public void merge(final LogicalDatastoreType store, final YangInstanceIdentifier path, final NormalizedNode data) {
 120         checkOpen();
 121         LOG.debug("{}: Merge {} {}", id, store, path);
 122         processTransactionOperation(facade -> facade.merge(store, path, data));
 123     }
 124
 125     @Override
 126     public @NonNull FluentFuture<? extends @NonNull CommitInfo> commit() {
 127         Preconditions.checkState(opened.compareAndSet(true, false), "%s: Transaction is already closed", id);
 128         LOG.debug("{}: Commit", id);
 129
 130         final SettableFuture<CommitInfo> returnFuture = SettableFuture.create();
 131         processTransactionOperation(facade -> returnFuture.setFuture(facade.commit()));
 132         return FluentFuture.from(returnFuture);
 133     }
 134
 135     @Override
 136     public Object getIdentifier() {
 137         return id;
 138     }
 139
 140     private void processTransactionOperation(final Consumer<ProxyTransactionFacade> operation) {
 141         final ProxyTransactionFacade facadeOnEntry;
 142         synchronized (queuedTxOperations) {
 143             if (transactionFacade == null) {
 144                 LOG.debug("{}: Queuing transaction operation", id);
 145
 146                 queuedTxOperations.add(operation);
 147                 facadeOnEntry = null;
 148             }  else {
 149                 facadeOnEntry = transactionFacade;
 150             }
 151         }
 152
 153         if (facadeOnEntry != null) {
 154             operation.accept(facadeOnEntry);
 155         }
 156     }
 157
 158     @SuppressFBWarnings(value = "UPM_UNCALLED_PRIVATE_METHOD",
 159             justification = "https://github.com/spotbugs/spotbugs/issues/811")
 160     private void executePriorTransactionOperations(final ProxyTransactionFacade newTransactionFacade) {
 161         while (true) {
 162             // Access to queuedTxOperations and transactionFacade must be protected and atomic
 163             // (ie synchronized) with respect to #processTransactionOperation to handle timing
 164             // issues and ensure no ProxyTransactionFacade is missed and that they are processed
 165             // in the order they occurred.
 166
 167             // We'll make a local copy of the queuedTxOperations list to handle re-entrancy
 168             // in case a transaction operation results in another transaction operation being
 169             // queued (eg a put operation from a client read Future callback that is notified
 170             // synchronously).
 171             final Collection<Consumer<ProxyTransactionFacade>> operationsBatch;
 172             synchronized (queuedTxOperations) {
 173                 if (queuedTxOperations.isEmpty()) {
 174                     // We're done invoking the transaction operations so we can now publish the
 175                     // ProxyTransactionFacade.
 176                     transactionFacade = newTransactionFacade;
 177                     break;
 178                 }
 179
 180                 operationsBatch = new ArrayList<>(queuedTxOperations);
 181                 queuedTxOperations.clear();
 182             }
 183
 184             // Invoke transaction operations outside the sync block to avoid unnecessary blocking.
 185             for (Consumer<ProxyTransactionFacade> oper : operationsBatch) {
 186                 oper.accept(newTransactionFacade);
 187             }
 188         }
 189     }
 190
 191     private void checkOpen() {
 192         Preconditions.checkState(opened.get(), "%s: Transaction is closed", id);
 193     }
 194 }