opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/FrontendMetadata.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 com.google.common.base.Verify.verify;
  11 import static java.util.Objects.requireNonNull;
  12
  13 import com.google.common.collect.Collections2;
  14 import com.google.common.collect.ImmutableSet;
  15 import com.google.common.collect.Maps;
  16 import java.util.HashMap;
  17 import java.util.Map;
  18 import org.eclipse.jdt.annotation.NonNull;
  19 import org.opendaylight.controller.cluster.access.concepts.ClientIdentifier;
  20 import org.opendaylight.controller.cluster.access.concepts.FrontendIdentifier;
  21 import org.opendaylight.controller.cluster.access.concepts.LocalHistoryIdentifier;
  22 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  23 import org.opendaylight.controller.cluster.datastore.persisted.FrontendClientMetadata;
  24 import org.opendaylight.controller.cluster.datastore.persisted.FrontendShardDataTreeSnapshotMetadata;
  25 import org.slf4j.Logger;
  26 import org.slf4j.LoggerFactory;
  27
  28 /**
  29  * Frontend state as observed by a shard follower. This class is responsible for maintaining metadata state
  30  * so that this can be used to seed {@link LeaderFrontendState} with proper state so that the frontend/backend
  31  * conversation can continue where it left off. This class is NOT thread-safe.
  32  *
  33  * @author Robert Varga
  34  */
  35 final class FrontendMetadata extends ShardDataTreeMetadata<FrontendShardDataTreeSnapshotMetadata> {
  36     private static final Logger LOG = LoggerFactory.getLogger(FrontendMetadata.class);
  37
  38     private final Map<FrontendIdentifier, FrontendClientMetadataBuilder> clients = new HashMap<>();
  39     private final String shardName;
  40
  41     FrontendMetadata(final String shardName) {
  42         this.shardName = requireNonNull(shardName);
  43     }
  44
  45     @Override
  46     Class<FrontendShardDataTreeSnapshotMetadata> getSupportedType() {
  47         return FrontendShardDataTreeSnapshotMetadata.class;
  48     }
  49
  50     @Override
  51     void reset() {
  52         LOG.debug("{}: clearing clients {}", shardName, clients);
  53         clients.clear();
  54     }
  55
  56     @Override
  57     void doApplySnapshot(final FrontendShardDataTreeSnapshotMetadata snapshot) {
  58         LOG.debug("{}: applying snapshot {} over clients {}", shardName, snapshot, clients);
  59         clients.clear();
  60
  61         for (FrontendClientMetadata m : snapshot.getClients()) {
  62             LOG.debug("{}: applying metadata {}", shardName, m);
  63             final FrontendClientMetadataBuilder b = FrontendClientMetadataBuilder.of(shardName, m);
  64             final FrontendIdentifier client = m.getIdentifier().getFrontendId();
  65
  66             LOG.debug("{}: client {} updated to {}", shardName, client, b);
  67             clients.put(client, b);
  68         }
  69     }
  70
  71     @Override
  72     FrontendShardDataTreeSnapshotMetadata toSnapshot() {
  73         return new FrontendShardDataTreeSnapshotMetadata(Collections2.transform(clients.values(),
  74             FrontendClientMetadataBuilder::build));
  75     }
  76
  77     private FrontendClientMetadataBuilder ensureClient(final ClientIdentifier id) {
  78         final FrontendClientMetadataBuilder existing = clients.get(id.getFrontendId());
  79         if (existing != null && id.equals(existing.getIdentifier())) {
  80             return existing;
  81         }
  82
  83         final FrontendClientMetadataBuilder client = new FrontendClientMetadataBuilder.Enabled(shardName, id);
  84         final FrontendClientMetadataBuilder previous = clients.put(id.getFrontendId(), client);
  85         if (previous != null) {
  86             LOG.debug("{}: Replaced client {} with {}", shardName, previous, client);
  87         } else {
  88             LOG.debug("{}: Added client {}", shardName, client);
  89         }
  90         return client;
  91     }
  92
  93     @Override
  94     void onHistoryCreated(final LocalHistoryIdentifier historyId) {
  95         ensureClient(historyId.getClientId()).onHistoryCreated(historyId);
  96     }
  97
  98     @Override
  99     void onHistoryClosed(final LocalHistoryIdentifier historyId) {
 100         ensureClient(historyId.getClientId()).onHistoryClosed(historyId);
 101     }
 102
 103     @Override
 104     void onHistoryPurged(final LocalHistoryIdentifier historyId) {
 105         ensureClient(historyId.getClientId()).onHistoryPurged(historyId);
 106     }
 107
 108     @Override
 109     void onTransactionAborted(final TransactionIdentifier txId) {
 110         ensureClient(txId.getHistoryId().getClientId()).onTransactionAborted(txId);
 111     }
 112
 113     @Override
 114     void onTransactionCommitted(final TransactionIdentifier txId) {
 115         ensureClient(txId.getHistoryId().getClientId()).onTransactionCommitted(txId);
 116     }
 117
 118     @Override
 119     void onTransactionPurged(final TransactionIdentifier txId) {
 120         ensureClient(txId.getHistoryId().getClientId()).onTransactionPurged(txId);
 121     }
 122
 123     /**
 124      * Transform frontend metadata into an active leader state map.
 125      *
 126      * @return Leader frontend state
 127      */
 128     @NonNull Map<FrontendIdentifier, LeaderFrontendState> toLeaderState(final @NonNull Shard shard) {
 129         return new HashMap<>(Maps.transformValues(clients, meta -> meta.toLeaderState(shard)));
 130     }
 131
 132     void disableTracking(final ClientIdentifier clientId) {
 133         final FrontendIdentifier frontendId = clientId.getFrontendId();
 134         final FrontendClientMetadataBuilder client = clients.get(frontendId);
 135         if (client == null) {
 136             // When we havent seen the client before, we still need to disable tracking for him since this only gets
 137             // triggered once.
 138             LOG.debug("{}: disableTracking {} does not match any client, pre-disabling client.", shardName, clientId);
 139             clients.put(frontendId, new FrontendClientMetadataBuilder.Disabled(shardName, clientId));
 140             return;
 141         }
 142         if (!clientId.equals(client.getIdentifier())) {
 143             LOG.debug("{}: disableTracking {} does not match client {}, ignoring", shardName, clientId, client);
 144             return;
 145         }
 146         if (client instanceof FrontendClientMetadataBuilder.Disabled) {
 147             LOG.debug("{}: client {} is has already disabled tracking", shardName, client);
 148             return;
 149         }
 150
 151         verify(clients.replace(frontendId, client, new FrontendClientMetadataBuilder.Disabled(shardName, clientId)));
 152     }
 153
 154     ImmutableSet<ClientIdentifier> getClients() {
 155         return clients.values().stream()
 156                 .map(FrontendClientMetadataBuilder::getIdentifier)
 157                 .collect(ImmutableSet.toImmutableSet());
 158     }
 159 }