opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/LocalFrontendHistory.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.datastore;
   9
  10 import com.google.common.base.Preconditions;
  11 import org.opendaylight.controller.cluster.access.commands.DeadTransactionException;
  12 import org.opendaylight.controller.cluster.access.commands.LocalHistorySuccess;
  13 import org.opendaylight.controller.cluster.access.concepts.LocalHistoryIdentifier;
  14 import org.opendaylight.controller.cluster.access.concepts.RequestEnvelope;
  15 import org.opendaylight.controller.cluster.access.concepts.RequestException;
  16 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  17 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  18 import org.slf4j.Logger;
  19 import org.slf4j.LoggerFactory;
  20
  21
  22 /**
  23  * Chained transaction specialization of {@link AbstractFrontendHistory}. It prevents concurrent open transactions.
  24  *
  25  * @author Robert Varga
  26  */
  27 final class LocalFrontendHistory extends AbstractFrontendHistory {
  28     private static final Logger LOG = LoggerFactory.getLogger(LocalFrontendHistory.class);
  29
  30     private final ShardDataTreeTransactionChain chain;
  31     private final ShardDataTree tree;
  32
  33     private Long lastSeenTransaction;
  34
  35     LocalFrontendHistory(final String persistenceId, final ShardDataTree tree,
  36             final ShardDataTreeTransactionChain chain) {
  37         super(persistenceId, tree.ticker());
  38         this.tree = Preconditions.checkNotNull(tree);
  39         this.chain = Preconditions.checkNotNull(chain);
  40     }
  41
  42     @Override
  43     public LocalHistoryIdentifier getIdentifier() {
  44         return chain.getIdentifier();
  45     }
  46
  47     @Override
  48     FrontendTransaction createOpenSnapshot(final TransactionIdentifier id) throws RequestException {
  49         checkDeadTransaction(id);
  50         lastSeenTransaction = id.getTransactionId();
  51         return FrontendReadOnlyTransaction.create(this, chain.newReadOnlyTransaction(id));
  52     }
  53
  54     @Override
  55     FrontendTransaction createOpenTransaction(final TransactionIdentifier id) throws RequestException {
  56         checkDeadTransaction(id);
  57         lastSeenTransaction = id.getTransactionId();
  58         return FrontendReadWriteTransaction.createOpen(this, chain.newReadWriteTransaction(id));
  59     }
  60
  61     @Override
  62     FrontendTransaction createReadyTransaction(final TransactionIdentifier id, final DataTreeModification mod)
  63             throws RequestException {
  64         checkDeadTransaction(id);
  65         lastSeenTransaction = id.getTransactionId();
  66         return FrontendReadWriteTransaction.createReady(this, id, mod);
  67     }
  68
  69     @Override
  70     ShardDataTreeCohort createReadyCohort(final TransactionIdentifier id, final DataTreeModification mod) {
  71         return chain.createReadyCohort(id, mod);
  72     }
  73
  74     void destroy(final long sequence, final RequestEnvelope envelope, final long now)
  75             throws RequestException {
  76         LOG.debug("{}: closing history {}", persistenceId(), getIdentifier());
  77         tree.closeTransactionChain(getIdentifier(), () -> {
  78             envelope.sendSuccess(new LocalHistorySuccess(getIdentifier(), sequence), readTime() - now);
  79         });
  80     }
  81
  82     void purge(final long sequence, final RequestEnvelope envelope, final long now) {
  83         LOG.debug("{}: purging history {}", persistenceId(), getIdentifier());
  84         tree.purgeTransactionChain(getIdentifier(), () -> {
  85             envelope.sendSuccess(new LocalHistorySuccess(getIdentifier(), sequence), readTime() - now);
  86         });
  87     }
  88
  89     private void checkDeadTransaction(final TransactionIdentifier id) throws RequestException {
  90         // FIXME: check if this history is still open
  91         // FIXME: check if the last transaction has been submitted
  92
  93         // Transaction identifiers within a local history have to have increasing IDs
  94         if (lastSeenTransaction != null && Long.compareUnsigned(lastSeenTransaction, id.getTransactionId()) >= 0) {
  95             throw new DeadTransactionException(lastSeenTransaction);
  96         }
  97     }
  98 }