opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/LocalReadOnlyProxyTransaction.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.Preconditions;
  11 import com.google.common.base.Verify;
  12 import java.util.function.Consumer;
  13 import javax.annotation.concurrent.NotThreadSafe;
  14 import org.opendaylight.controller.cluster.access.commands.AbortLocalTransactionRequest;
  15 import org.opendaylight.controller.cluster.access.commands.CommitLocalTransactionRequest;
  16 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequest;
  17 import org.opendaylight.controller.cluster.access.commands.PersistenceProtocol;
  18 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
  19 import org.opendaylight.controller.cluster.access.concepts.Response;
  20 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  21 import org.opendaylight.controller.cluster.datastore.util.AbstractDataTreeModificationCursor;
  22 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  23 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  24 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  25 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  26 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  27 import org.slf4j.Logger;
  28 import org.slf4j.LoggerFactory;
  29
  30 /**
  31  * A read-only specialization of {@link LocalProxyTransaction}.
  32  *
  33  * @author Robert Varga
  34  */
  35 @NotThreadSafe
  36 final class LocalReadOnlyProxyTransaction extends LocalProxyTransaction {
  37     private static final Logger LOG = LoggerFactory.getLogger(LocalReadOnlyProxyTransaction.class);
  38
  39     private final DataTreeSnapshot snapshot;
  40
  41     LocalReadOnlyProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier,
  42         final DataTreeSnapshot snapshot) {
  43         super(parent, identifier);
  44         this.snapshot = Preconditions.checkNotNull(snapshot);
  45     }
  46
  47     @Override
  48     boolean isSnapshotOnly() {
  49         return true;
  50     }
  51
  52     @Override
  53     DataTreeSnapshot readOnlyView() {
  54         return snapshot;
  55     }
  56
  57     @Override
  58     void doDelete(final YangInstanceIdentifier path) {
  59         throw new UnsupportedOperationException("Read-only snapshot");
  60     }
  61
  62     @Override
  63     void doMerge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  64         throw new UnsupportedOperationException("Read-only snapshot");
  65     }
  66
  67     @Override
  68     void doWrite(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  69         throw new UnsupportedOperationException("Read-only snapshot");
  70     }
  71
  72     @Override
  73     CommitLocalTransactionRequest commitRequest(final boolean coordinated) {
  74         throw new UnsupportedOperationException("Read-only snapshot");
  75     }
  76
  77     @Override
  78     void doSeal() {
  79         // No-op
  80     }
  81
  82     @Override
  83     void flushState(final AbstractProxyTransaction successor) {
  84         // No-op
  85     }
  86
  87     @Override
  88     void applyModifyTransactionRequest(final ModifyTransactionRequest request,
  89             final Consumer<Response<?, ?>> callback) {
  90         Verify.verify(request.getModifications().isEmpty());
  91
  92         final PersistenceProtocol protocol = request.getPersistenceProtocol().get();
  93         Verify.verify(protocol == PersistenceProtocol.ABORT);
  94         abort();
  95     }
  96
  97     @Override
  98     void forwardToRemote(final RemoteProxyTransaction successor, final TransactionRequest<?> request,
  99             final Consumer<Response<?, ?>> callback) {
 100         if (request instanceof CommitLocalTransactionRequest) {
 101             final CommitLocalTransactionRequest req = (CommitLocalTransactionRequest) request;
 102             final DataTreeModification mod = req.getModification();
 103
 104             LOG.debug("Applying modification {} to successor {}", mod, successor);
 105             mod.applyToCursor(new AbstractDataTreeModificationCursor() {
 106                 @Override
 107                 public void write(final PathArgument child, final NormalizedNode<?, ?> data) {
 108                     successor.write(current().node(child), data);
 109                 }
 110
 111                 @Override
 112                 public void merge(final PathArgument child, final NormalizedNode<?, ?> data) {
 113                     successor.merge(current().node(child), data);
 114                 }
 115
 116                 @Override
 117                 public void delete(final PathArgument child) {
 118                     successor.delete(current().node(child));
 119                 }
 120             });
 121
 122             successor.ensureSealed();
 123
 124             final ModifyTransactionRequest successorReq = successor.commitRequest(req.isCoordinated());
 125             successor.sendRequest(successorReq, callback);
 126         } else if (request instanceof AbortLocalTransactionRequest) {
 127             LOG.debug("Forwarding abort {} to successor {}", request, successor);
 128             successor.abort();
 129         } else {
 130             throw new IllegalArgumentException("Unhandled request" + request);
 131         }
 132     }
 133 }