opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/AbstractFrontendHistory.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 static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.base.MoreObjects;
  13 import com.google.common.collect.ImmutableMap;
  14 import com.google.common.primitives.UnsignedLong;
  15 import java.util.HashMap;
  16 import java.util.Map;
  17 import java.util.Optional;
  18 import java.util.SortedSet;
  19 import org.eclipse.jdt.annotation.Nullable;
  20 import org.opendaylight.controller.cluster.access.commands.AbstractReadTransactionRequest;
  21 import org.opendaylight.controller.cluster.access.commands.ClosedTransactionException;
  22 import org.opendaylight.controller.cluster.access.commands.CommitLocalTransactionRequest;
  23 import org.opendaylight.controller.cluster.access.commands.DeadTransactionException;
  24 import org.opendaylight.controller.cluster.access.commands.IncrementTransactionSequenceRequest;
  25 import org.opendaylight.controller.cluster.access.commands.LocalHistorySuccess;
  26 import org.opendaylight.controller.cluster.access.commands.OutOfOrderRequestException;
  27 import org.opendaylight.controller.cluster.access.commands.TransactionPurgeRequest;
  28 import org.opendaylight.controller.cluster.access.commands.TransactionPurgeResponse;
  29 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
  30 import org.opendaylight.controller.cluster.access.commands.TransactionSuccess;
  31 import org.opendaylight.controller.cluster.access.concepts.LocalHistoryIdentifier;
  32 import org.opendaylight.controller.cluster.access.concepts.RequestEnvelope;
  33 import org.opendaylight.controller.cluster.access.concepts.RequestException;
  34 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  35 import org.opendaylight.controller.cluster.datastore.utils.UnsignedLongSet;
  36 import org.opendaylight.yangtools.concepts.Identifiable;
  37 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  38 import org.slf4j.Logger;
  39 import org.slf4j.LoggerFactory;
  40
  41 /**
  42  * Abstract class for providing logical tracking of frontend local histories. This class is specialized for
  43  * standalone transactions and chained transactions.
  44  *
  45  * @author Robert Varga
  46  */
  47 abstract class AbstractFrontendHistory implements Identifiable<LocalHistoryIdentifier> {
  48     private static final Logger LOG = LoggerFactory.getLogger(AbstractFrontendHistory.class);
  49
  50     private final Map<TransactionIdentifier, FrontendTransaction> transactions = new HashMap<>();
  51     private final UnsignedLongSet purgedTransactions;
  52     private final String persistenceId;
  53     private final ShardDataTree tree;
  54
  55     /**
  56      * Transactions closed by the previous leader. Boolean indicates whether the transaction was committed (true) or
  57      * aborted (false). We only ever shrink these.
  58      */
  59     private Map<UnsignedLong, Boolean> closedTransactions;
  60
  61     AbstractFrontendHistory(final String persistenceId, final ShardDataTree tree,
  62         final Map<UnsignedLong, Boolean> closedTransactions, final UnsignedLongSet purgedTransactions) {
  63         this.persistenceId = requireNonNull(persistenceId);
  64         this.tree = requireNonNull(tree);
  65         this.closedTransactions = requireNonNull(closedTransactions);
  66         this.purgedTransactions = requireNonNull(purgedTransactions);
  67     }
  68
  69     final String persistenceId() {
  70         return persistenceId;
  71     }
  72
  73     final long readTime() {
  74         return tree.readTime();
  75     }
  76
  77     final @Nullable TransactionSuccess<?> handleTransactionRequest(final TransactionRequest<?> request,
  78             final RequestEnvelope envelope, final long now) throws RequestException {
  79         if (request instanceof TransactionPurgeRequest) {
  80             return handleTransactionPurgeRequest(request, envelope, now);
  81         }
  82
  83         final TransactionIdentifier id = request.getTarget();
  84         final long txidBits = id.getTransactionId();
  85         if (purgedTransactions.contains(txidBits)) {
  86             LOG.warn("{}: Request {} is contained purged transactions {}", persistenceId, request, purgedTransactions);
  87             throw new DeadTransactionException(purgedTransactions.toRangeSet());
  88         }
  89
  90         final Boolean closed = closedTransactions.get(UnsignedLong.fromLongBits(txidBits));
  91         if (closed != null) {
  92             final boolean successful = closed;
  93             LOG.debug("{}: Request {} refers to a {} transaction", persistenceId, request, successful ? "successful"
  94                     : "failed");
  95             throw new ClosedTransactionException(successful);
  96         }
  97
  98         FrontendTransaction tx = transactions.get(id);
  99         if (tx == null) {
 100             // The transaction does not exist and we are about to create it, check sequence number
 101             if (request.getSequence() != 0) {
 102                 LOG.warn("{}: no transaction state present, unexpected request {}", persistenceId(), request);
 103                 throw new OutOfOrderRequestException(0);
 104             }
 105
 106             tx = createTransaction(request, id);
 107             transactions.put(id, tx);
 108         } else if (!(request instanceof IncrementTransactionSequenceRequest)) {
 109             final Optional<TransactionSuccess<?>> maybeReplay = tx.replaySequence(request.getSequence());
 110             if (maybeReplay.isPresent()) {
 111                 final TransactionSuccess<?> replay = maybeReplay.get();
 112                 LOG.debug("{}: envelope {} replaying response {}", persistenceId(), envelope, replay);
 113                 return replay;
 114             }
 115         }
 116
 117         return tx.handleRequest(request, envelope, now);
 118     }
 119
 120     private TransactionSuccess<?> handleTransactionPurgeRequest(final TransactionRequest<?> request,
 121             final RequestEnvelope envelope, final long now) {
 122         final TransactionIdentifier id = request.getTarget();
 123         final long txidBits = id.getTransactionId();
 124         if (purgedTransactions.contains(txidBits)) {
 125             // Retransmitted purge request: nothing to do
 126             LOG.debug("{}: transaction {} already purged", persistenceId, id);
 127             return new TransactionPurgeResponse(id, request.getSequence());
 128         }
 129
 130         // We perform two lookups instead of a straight remove, because once the map becomes empty we switch it
 131         // to an ImmutableMap, which does not allow remove().
 132         final UnsignedLong ul = UnsignedLong.fromLongBits(txidBits);
 133         if (closedTransactions.containsKey(ul)) {
 134             tree.purgeTransaction(id, () -> {
 135                 closedTransactions.remove(ul);
 136                 if (closedTransactions.isEmpty()) {
 137                     closedTransactions = ImmutableMap.of();
 138                 }
 139
 140                 purgedTransactions.add(txidBits);
 141                 LOG.debug("{}: finished purging inherited transaction {}", persistenceId(), id);
 142                 envelope.sendSuccess(new TransactionPurgeResponse(id, request.getSequence()), readTime() - now);
 143             });
 144             return null;
 145         }
 146
 147         final FrontendTransaction tx = transactions.get(id);
 148         if (tx == null) {
 149             // This should never happen because the purge callback removes the transaction and puts it into
 150             // purged transactions in one go. If it does, we warn about the situation and
 151             LOG.warn("{}: transaction {} not tracked in {}, but not present in active transactions", persistenceId,
 152                 id, purgedTransactions);
 153             purgedTransactions.add(txidBits);
 154             return new TransactionPurgeResponse(id, request.getSequence());
 155         }
 156
 157         tree.purgeTransaction(id, () -> {
 158             purgedTransactions.add(txidBits);
 159             transactions.remove(id);
 160             LOG.debug("{}: finished purging transaction {}", persistenceId(), id);
 161             envelope.sendSuccess(new TransactionPurgeResponse(id, request.getSequence()), readTime() - now);
 162         });
 163
 164         return null;
 165     }
 166
 167     final void destroy(final long sequence, final RequestEnvelope envelope, final long now) {
 168         LOG.debug("{}: closing history {}", persistenceId(), getIdentifier());
 169         tree.closeTransactionChain(getIdentifier(),
 170             () -> envelope.sendSuccess(new LocalHistorySuccess(getIdentifier(), sequence), readTime() - now));
 171     }
 172
 173     final void purge(final long sequence, final RequestEnvelope envelope, final long now) {
 174         LOG.debug("{}: purging history {}", persistenceId(), getIdentifier());
 175         tree.purgeTransactionChain(getIdentifier(),
 176             () -> envelope.sendSuccess(new LocalHistorySuccess(getIdentifier(), sequence), readTime() - now));
 177     }
 178
 179     final void retire() {
 180         transactions.values().forEach(FrontendTransaction::retire);
 181         tree.removeTransactionChain(getIdentifier());
 182     }
 183
 184     private FrontendTransaction createTransaction(final TransactionRequest<?> request, final TransactionIdentifier id) {
 185         if (request instanceof CommitLocalTransactionRequest) {
 186             LOG.debug("{}: allocating new ready transaction {}", persistenceId(), id);
 187             tree.getStats().incrementReadWriteTransactionCount();
 188             return createReadyTransaction(id, ((CommitLocalTransactionRequest) request).getModification());
 189         }
 190         if (request instanceof AbstractReadTransactionRequest
 191                 && ((AbstractReadTransactionRequest<?>) request).isSnapshotOnly()) {
 192             LOG.debug("{}: allocating new open snapshot {}", persistenceId(), id);
 193             tree.getStats().incrementReadOnlyTransactionCount();
 194             return createOpenSnapshot(id);
 195         }
 196
 197         LOG.debug("{}: allocating new open transaction {}", persistenceId(), id);
 198         tree.getStats().incrementReadWriteTransactionCount();
 199         return createOpenTransaction(id);
 200     }
 201
 202     abstract FrontendTransaction createOpenSnapshot(TransactionIdentifier id);
 203
 204     abstract FrontendTransaction createOpenTransaction(TransactionIdentifier id);
 205
 206     abstract FrontendTransaction createReadyTransaction(TransactionIdentifier id, DataTreeModification mod)
 207         ;
 208
 209     abstract ShardDataTreeCohort createFailedCohort(TransactionIdentifier id, DataTreeModification mod,
 210             Exception failure);
 211
 212     abstract ShardDataTreeCohort createReadyCohort(TransactionIdentifier id, DataTreeModification mod,
 213             Optional<SortedSet<String>> participatingShardNames);
 214
 215     @Override
 216     public String toString() {
 217         return MoreObjects.toStringHelper(this).omitNullValues().add("identifier", getIdentifier())
 218                 .add("persistenceId", persistenceId).add("transactions", transactions).toString();
 219     }
 220 }