opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/RemoteProxyTransaction.java

   1 /*
   2  * Copyright (c) 2016 Cisco Systems, Inc. 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.controller.cluster.databroker.actors.dds;
   9
  10 import com.google.common.base.Optional;
  11 import com.google.common.util.concurrent.CheckedFuture;
  12 import com.google.common.util.concurrent.Futures;
  13 import com.google.common.util.concurrent.ListenableFuture;
  14 import com.google.common.util.concurrent.SettableFuture;
  15 import java.util.function.Consumer;
  16 import org.opendaylight.controller.cluster.access.commands.AbstractReadTransactionRequest;
  17 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionRequest;
  18 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionSuccess;
  19 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequest;
  20 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequestBuilder;
  21 import org.opendaylight.controller.cluster.access.commands.ReadTransactionRequest;
  22 import org.opendaylight.controller.cluster.access.commands.ReadTransactionSuccess;
  23 import org.opendaylight.controller.cluster.access.commands.TransactionDelete;
  24 import org.opendaylight.controller.cluster.access.commands.TransactionMerge;
  25 import org.opendaylight.controller.cluster.access.commands.TransactionModification;
  26 import org.opendaylight.controller.cluster.access.commands.TransactionSuccess;
  27 import org.opendaylight.controller.cluster.access.commands.TransactionWrite;
  28 import org.opendaylight.controller.cluster.access.concepts.RequestFailure;
  29 import org.opendaylight.controller.cluster.access.concepts.Response;
  30 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  31 import org.opendaylight.controller.md.sal.common.api.data.ReadFailedException;
  32 import org.opendaylight.yangtools.util.concurrent.MappingCheckedFuture;
  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
  38 /**
  39  * An {@link AbstractProxyTransaction} for dispatching a transaction towards a shard leader whose location is currently
  40  * not known or is known to be not co-located with the client.
  41  *
  42  * It packages operations and sends them via the client actor queue to the shard leader. That queue is responsible for
  43  * maintaining any submitted operations until the leader is discovered.
  44  *
  45  * This class is not safe to access from multiple application threads, as is usual for transactions. Its internal state
  46  * transitions based on backend responses are thread-safe.
  47  *
  48  * @author Robert Varga
  49  */
  50 final class RemoteProxyTransaction extends AbstractProxyTransaction {
  51     private static final Logger LOG = LoggerFactory.getLogger(RemoteProxyTransaction.class);
  52
  53     // FIXME: make this tuneable
  54     private static final int REQUEST_MAX_MODIFICATIONS = 1000;
  55
  56     private final ModifyTransactionRequestBuilder builder;
  57
  58     private boolean builderBusy;
  59
  60     private volatile Exception operationFailure;
  61
  62     RemoteProxyTransaction(final DistributedDataStoreClientBehavior client,
  63         final TransactionIdentifier identifier) {
  64         super(client);
  65         builder = new ModifyTransactionRequestBuilder(identifier, localActor());
  66     }
  67
  68     @Override
  69     public TransactionIdentifier getIdentifier() {
  70         return builder.getIdentifier();
  71     }
  72
  73     @Override
  74     void doDelete(final YangInstanceIdentifier path) {
  75         appendModification(new TransactionDelete(path));
  76     }
  77
  78     @Override
  79     void doMerge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  80         appendModification(new TransactionMerge(path, data));
  81     }
  82
  83     @Override
  84     void doWrite(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  85         appendModification(new TransactionWrite(path, data));
  86     }
  87
  88     private <T> CheckedFuture<T, ReadFailedException> sendReadRequest(final AbstractReadTransactionRequest<?> request,
  89             final Consumer<Response<?, ?>> completer, final ListenableFuture<T> future) {
  90         // Check if a previous operation failed. If it has, do not bother sending anything and report a failure
  91         final Exception local = operationFailure;
  92         if (local != null) {
  93             return Futures.immediateFailedCheckedFuture(new ReadFailedException("Previous operation failed", local));
  94         }
  95
  96         // Make sure we send any modifications before issuing a read
  97         ensureFlushedBuider();
  98         sendRequest(request, completer);
  99         return MappingCheckedFuture.create(future, ReadFailedException.MAPPER);
 100     }
 101
 102     @Override
 103     CheckedFuture<Boolean, ReadFailedException> doExists(final YangInstanceIdentifier path) {
 104         final SettableFuture<Boolean> future = SettableFuture.create();
 105         return sendReadRequest(new ExistsTransactionRequest(getIdentifier(), nextSequence(), localActor(), path),
 106             t -> completeExists(future, t), future);
 107     }
 108
 109     @Override
 110     CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> doRead(final YangInstanceIdentifier path) {
 111         final SettableFuture<Optional<NormalizedNode<?, ?>>> future = SettableFuture.create();
 112         return sendReadRequest(new ReadTransactionRequest(getIdentifier(), nextSequence(), localActor(), path),
 113             t -> completeRead(future, t), future);
 114     }
 115
 116     @Override
 117     void doAbort() {
 118         ensureInitializedBuider();
 119         builder.setAbort();
 120         flushBuilder();
 121     }
 122
 123     private void ensureInitializedBuider() {
 124         if (!builderBusy) {
 125             builder.setSequence(nextSequence());
 126             builderBusy = true;
 127         }
 128     }
 129
 130     private void ensureFlushedBuider() {
 131         if (builderBusy) {
 132             flushBuilder();
 133         }
 134     }
 135
 136     private void flushBuilder() {
 137         final ModifyTransactionRequest message = builder.build();
 138         builderBusy = false;
 139
 140         sendRequest(message, this::completeModify);
 141     }
 142
 143     private void appendModification(final TransactionModification modification) {
 144         if (operationFailure == null) {
 145             ensureInitializedBuider();
 146
 147             builder.addModification(modification);
 148             if (builder.size() >= REQUEST_MAX_MODIFICATIONS) {
 149                 flushBuilder();
 150             }
 151         } else {
 152             LOG.debug("Transaction {} failed, not attempting further transactions", getIdentifier());
 153         }
 154     }
 155
 156     private void completeModify(final Response<?, ?> response) {
 157         LOG.debug("Modification request completed with {}", response);
 158
 159         if (response instanceof TransactionSuccess) {
 160             // Happy path no-op
 161         } else {
 162             recordFailedResponse(response);
 163         }
 164     }
 165
 166     private Exception recordFailedResponse(final Response<?, ?> response) {
 167         final Exception failure;
 168         if (response instanceof RequestFailure) {
 169             failure = ((RequestFailure<?, ?>) response).getCause();
 170         } else {
 171             LOG.warn("Unhandled response {}", response);
 172             failure = new IllegalArgumentException("Unhandled response " + response.getClass());
 173         }
 174
 175         if (operationFailure == null) {
 176             LOG.debug("Transaction {} failed", getIdentifier(), failure);
 177             operationFailure = failure;
 178         }
 179         return failure;
 180     }
 181
 182     private void failFuture(final SettableFuture<?> future, final Response<?, ?> response) {
 183         future.setException(recordFailedResponse(response));
 184     }
 185
 186     private void completeExists(final SettableFuture<Boolean> future, final Response<?, ?> response) {
 187         LOG.debug("Exists request completed with {}", response);
 188
 189         if (response instanceof ExistsTransactionSuccess) {
 190             future.set(((ExistsTransactionSuccess) response).getExists());
 191         } else {
 192             failFuture(future, response);
 193         }
 194     }
 195
 196     private void completeRead(final SettableFuture<Optional<NormalizedNode<?, ?>>> future, final Response<?, ?> response) {
 197         LOG.debug("Read request completed with {}", response);
 198
 199         if (response instanceof ReadTransactionSuccess) {
 200             future.set(((ReadTransactionSuccess) response).getData());
 201         } else {
 202             failFuture(future, response);
 203         }
 204     }
 205
 206     @Override
 207     ModifyTransactionRequest doCommit(final boolean coordinated) {
 208         ensureInitializedBuider();
 209         builder.setCommit(coordinated);
 210
 211         final ModifyTransactionRequest ret = builder.build();
 212         builderBusy = false;
 213         return ret;
 214     }
 215
 216     @Override
 217     void doSeal() {
 218         // No-op
 219     }
 220 }