opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/LocalProxyTransaction.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 static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.util.concurrent.FluentFuture;
  13 import java.util.Optional;
  14 import java.util.function.Consumer;
  15 import org.eclipse.jdt.annotation.NonNull;
  16 import org.eclipse.jdt.annotation.Nullable;
  17 import org.opendaylight.controller.cluster.access.commands.AbortLocalTransactionRequest;
  18 import org.opendaylight.controller.cluster.access.commands.AbstractLocalTransactionRequest;
  19 import org.opendaylight.controller.cluster.access.commands.CommitLocalTransactionRequest;
  20 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionRequest;
  21 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionSuccess;
  22 import org.opendaylight.controller.cluster.access.commands.IncrementTransactionSequenceRequest;
  23 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequest;
  24 import org.opendaylight.controller.cluster.access.commands.ReadTransactionRequest;
  25 import org.opendaylight.controller.cluster.access.commands.ReadTransactionSuccess;
  26 import org.opendaylight.controller.cluster.access.commands.TransactionPurgeRequest;
  27 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
  28 import org.opendaylight.controller.cluster.access.concepts.Response;
  29 import org.opendaylight.controller.cluster.access.concepts.RuntimeRequestException;
  30 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  31 import org.opendaylight.controller.cluster.datastore.util.AbstractDataTreeModificationCursor;
  32 import org.opendaylight.mdsal.common.api.ReadFailedException;
  33 import org.opendaylight.yangtools.util.concurrent.FluentFutures;
  34 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  35 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  36 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  37 import org.opendaylight.yangtools.yang.data.tree.api.DataTreeModification;
  38 import org.opendaylight.yangtools.yang.data.tree.api.DataTreeSnapshot;
  39 import org.slf4j.Logger;
  40 import org.slf4j.LoggerFactory;
  41
  42 /**
  43  * An {@link AbstractProxyTransaction} for dispatching a transaction towards a shard leader which is co-located with
  44  * the client instance. This class is NOT thread-safe.
  45  *
  46  * <p>
  47  * It requires a {@link DataTreeSnapshot}, which is used to instantiated a new {@link DataTreeModification}. Operations
  48  * are then performed on this modification and once the transaction is submitted, the modification is sent to the shard
  49  * leader.
  50  *
  51  * <p>
  52  * This class is not thread-safe as usual with transactions. Since it does not interact with the backend until the
  53  * transaction is submitted, at which point this class gets out of the picture, this is not a cause for concern.
  54  *
  55  * @author Robert Varga
  56  */
  57 // FIXME: sealed when we have JDK17+
  58 abstract class LocalProxyTransaction extends AbstractProxyTransaction {
  59     private static final Logger LOG = LoggerFactory.getLogger(LocalProxyTransaction.class);
  60
  61     private final @NonNull TransactionIdentifier identifier;
  62
  63     LocalProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier, final boolean isDone) {
  64         super(parent, isDone);
  65         this.identifier = requireNonNull(identifier);
  66     }
  67
  68     @Override
  69     public final TransactionIdentifier getIdentifier() {
  70         return identifier;
  71     }
  72
  73     abstract @NonNull DataTreeSnapshot readOnlyView();
  74
  75     abstract void applyForwardedModifyTransactionRequest(ModifyTransactionRequest request,
  76             @Nullable Consumer<Response<?, ?>> callback);
  77
  78     abstract void replayModifyTransactionRequest(ModifyTransactionRequest request,
  79             @Nullable Consumer<Response<?, ?>> callback, long enqueuedTicks);
  80
  81     @Override
  82     FluentFuture<Boolean> doExists(final YangInstanceIdentifier path) {
  83         final boolean result;
  84         try {
  85             result = readOnlyView().readNode(path).isPresent();
  86         } catch (FailedDataTreeModificationException e) {
  87             return FluentFutures.immediateFailedFluentFuture(ReadFailedException.MAPPER.apply(e));
  88         }
  89         return FluentFutures.immediateBooleanFluentFuture(result);
  90     }
  91
  92     @Override
  93     FluentFuture<Optional<NormalizedNode>> doRead(final YangInstanceIdentifier path) {
  94         final Optional<NormalizedNode> result;
  95         try {
  96             result = readOnlyView().readNode(path);
  97         } catch (FailedDataTreeModificationException e) {
  98             return FluentFutures.immediateFailedFluentFuture(ReadFailedException.MAPPER.apply(e));
  99         }
 100         return FluentFutures.immediateFluentFuture(result);
 101     }
 102
 103     @Override
 104     final AbortLocalTransactionRequest abortRequest() {
 105         return new AbortLocalTransactionRequest(identifier, localActor());
 106     }
 107
 108     @Override
 109     void handleReplayedLocalRequest(final AbstractLocalTransactionRequest<?> request,
 110             final Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
 111         if (request instanceof AbortLocalTransactionRequest) {
 112             enqueueAbort(request, callback, enqueuedTicks);
 113         } else {
 114             throw unhandledRequest(request);
 115         }
 116     }
 117
 118     @Override
 119     void handleReplayedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback,
 120             final long enqueuedTicks) {
 121         if (request instanceof ModifyTransactionRequest) {
 122             replayModifyTransactionRequest((ModifyTransactionRequest) request, callback, enqueuedTicks);
 123         } else if (handleReadRequest(request, callback)) {
 124             // No-op
 125         } else if (request instanceof TransactionPurgeRequest) {
 126             enqueuePurge(callback, enqueuedTicks);
 127         } else if (request instanceof IncrementTransactionSequenceRequest) {
 128             // Local transactions do not have non-replayable requests which would be visible to the backend,
 129             // hence we can skip sequence increments.
 130             LOG.debug("Not replaying {}", request);
 131         } else {
 132             throw unhandledRequest(request);
 133         }
 134     }
 135
 136     /**
 137      * Remote-to-local equivalent of {@link #handleReplayedRemoteRequest(TransactionRequest, Consumer, long)},
 138      * except it is invoked in the forwarding path from
 139      * {@link RemoteProxyTransaction#forwardToLocal(LocalProxyTransaction, TransactionRequest, Consumer)}.
 140      *
 141      * @param request Forwarded request
 142      * @param callback Callback to be invoked once the request completes
 143      */
 144     void handleForwardedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 145         if (request instanceof ModifyTransactionRequest) {
 146             applyForwardedModifyTransactionRequest((ModifyTransactionRequest) request, callback);
 147         } else if (handleReadRequest(request, callback)) {
 148             // No-op
 149         } else if (request instanceof TransactionPurgeRequest) {
 150             enqueuePurge(callback);
 151         } else {
 152             throw unhandledRequest(request);
 153         }
 154     }
 155
 156     @NonNull Response<?, ?> handleExistsRequest(final @NonNull DataTreeSnapshot snapshot,
 157             final @NonNull ExistsTransactionRequest request) {
 158         try {
 159             return new ExistsTransactionSuccess(request.getTarget(), request.getSequence(),
 160                 snapshot.readNode(request.getPath()).isPresent());
 161         } catch (FailedDataTreeModificationException e) {
 162             return request.toRequestFailure(new RuntimeRequestException("Failed to access data",
 163                 ReadFailedException.MAPPER.apply(e)));
 164         }
 165     }
 166
 167     @NonNull Response<?, ?> handleReadRequest(final @NonNull DataTreeSnapshot snapshot,
 168             final @NonNull ReadTransactionRequest request) {
 169         try {
 170             return new ReadTransactionSuccess(request.getTarget(), request.getSequence(),
 171                 snapshot.readNode(request.getPath()));
 172         } catch (FailedDataTreeModificationException e) {
 173             return request.toRequestFailure(new RuntimeRequestException("Failed to access data",
 174                 ReadFailedException.MAPPER.apply(e)));
 175         }
 176     }
 177
 178     private boolean handleReadRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 179         // Note we delay completion of read requests to limit the scope at which the client can run, as they have
 180         // listeners, which we do not want to execute while we are reconnecting.
 181         if (request instanceof ReadTransactionRequest) {
 182             if (callback != null) {
 183                 final var response = handleReadRequest(readOnlyView(), (ReadTransactionRequest) request);
 184                 executeInActor(() -> callback.accept(response));
 185             }
 186             return true;
 187         } else if (request instanceof ExistsTransactionRequest) {
 188             if (callback != null) {
 189                 final var response = handleExistsRequest(readOnlyView(), (ExistsTransactionRequest) request);
 190                 executeInActor(() -> callback.accept(response));
 191             }
 192             return true;
 193         } else {
 194             return false;
 195         }
 196     }
 197
 198     @Override
 199     final void forwardToRemote(final RemoteProxyTransaction successor, final TransactionRequest<?> request,
 200                          final Consumer<Response<?, ?>> callback) {
 201         if (request instanceof CommitLocalTransactionRequest) {
 202             final CommitLocalTransactionRequest req = (CommitLocalTransactionRequest) request;
 203             final DataTreeModification mod = req.getModification();
 204
 205             LOG.debug("Applying modification {} to successor {}", mod, successor);
 206             mod.applyToCursor(new AbstractDataTreeModificationCursor() {
 207                 @Override
 208                 public void write(final PathArgument child, final NormalizedNode data) {
 209                     successor.write(current().node(child), data);
 210                 }
 211
 212                 @Override
 213                 public void merge(final PathArgument child, final NormalizedNode data) {
 214                     successor.merge(current().node(child), data);
 215                 }
 216
 217                 @Override
 218                 public void delete(final PathArgument child) {
 219                     successor.delete(current().node(child));
 220                 }
 221             });
 222
 223             successor.sealOnly();
 224             final ModifyTransactionRequest successorReq = successor.commitRequest(req.isCoordinated());
 225             successor.sendRequest(successorReq, callback);
 226         } else if (request instanceof AbortLocalTransactionRequest) {
 227             LOG.debug("Forwarding abort {} to successor {}", request, successor);
 228             successor.abort();
 229         } else if (request instanceof TransactionPurgeRequest) {
 230             LOG.debug("Forwarding purge {} to successor {}", request, successor);
 231             successor.enqueuePurge(callback);
 232         } else if (request instanceof ModifyTransactionRequest) {
 233             successor.handleForwardedRequest(request, callback);
 234         } else {
 235             throw unhandledRequest(request);
 236         }
 237     }
 238
 239     @Override
 240     void forwardToLocal(final LocalProxyTransaction successor, final TransactionRequest<?> request,
 241             final Consumer<Response<?, ?>> callback) {
 242         if (request instanceof AbortLocalTransactionRequest) {
 243             successor.sendAbort(request, callback);
 244         } else if (request instanceof TransactionPurgeRequest) {
 245             successor.enqueuePurge(callback);
 246         } else {
 247             throw unhandledRequest(request);
 248         }
 249
 250         LOG.debug("Forwarded request {} to successor {}", request, successor);
 251     }
 252
 253     void sendAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 254         sendRequest(request, callback);
 255     }
 256
 257     void enqueueAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback,
 258             final long enqueuedTicks) {
 259         enqueueRequest(request, callback, enqueuedTicks);
 260     }
 261 }