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 com.google.common.base.Preconditions;
  11 import com.google.common.collect.Collections2;
  12 import com.google.common.collect.Maps;
  13 import java.util.HashMap;
  14 import java.util.Map;
  15 import javax.annotation.Nonnull;
  16 import javax.annotation.concurrent.NotThreadSafe;
  17 import org.opendaylight.controller.cluster.access.concepts.ClientIdentifier;
  18 import org.opendaylight.controller.cluster.access.concepts.FrontendIdentifier;
  19 import org.opendaylight.controller.cluster.access.concepts.LocalHistoryIdentifier;
  20 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  21 import org.opendaylight.controller.cluster.datastore.persisted.FrontendClientMetadata;
  22 import org.opendaylight.controller.cluster.datastore.persisted.FrontendShardDataTreeSnapshotMetadata;
  23 import org.slf4j.Logger;
  24 import org.slf4j.LoggerFactory;
  25
  26 /**
  27  * Frontend state as observed by a shard follower. This class is responsible for maintaining metadata state
  28  * so that this can be used to seed {@link LeaderFrontendState} with proper state so that the frontend/backend
  29  * conversation can continue where it left off.
  30  *
  31  * @author Robert Varga
  32  */
  33 @NotThreadSafe
  34 final class FrontendMetadata extends ShardDataTreeMetadata<FrontendShardDataTreeSnapshotMetadata> {
  35     private static final Logger LOG = LoggerFactory.getLogger(FrontendMetadata.class);
  36
  37     private final Map<FrontendIdentifier, FrontendClientMetadataBuilder> clients = new HashMap<>();
  38     private final String shardName;
  39
  40     FrontendMetadata(final String shardName) {
  41         this.shardName = Preconditions.checkNotNull(shardName);
  42     }
  43
  44     @Override
  45     Class<FrontendShardDataTreeSnapshotMetadata> getSupportedType() {
  46         return FrontendShardDataTreeSnapshotMetadata.class;
  47     }
  48
  49     @Override
  50     void reset() {
  51         LOG.debug("{}: clearing clients {}", shardName, clients);
  52         clients.clear();
  53     }
  54
  55     @Override
  56     void doApplySnapshot(final FrontendShardDataTreeSnapshotMetadata snapshot) {
  57         LOG.debug("{}: applying snapshot {} over clients {}", shardName, snapshot, clients);
  58         clients.clear();
  59
  60         for (FrontendClientMetadata m : snapshot.getClients()) {
  61             LOG.debug("{}: applying metadata {}", shardName, m);
  62             final FrontendClientMetadataBuilder b = new FrontendClientMetadataBuilder(m);
  63             final FrontendIdentifier client = m.getIdentifier().getFrontendId();
  64
  65             LOG.debug("{}: client {} updated to {}", shardName, client, b);
  66             clients.put(client, b);
  67         }
  68     }
  69
  70     @Override
  71     FrontendShardDataTreeSnapshotMetadata toSnapshot() {
  72         return new FrontendShardDataTreeSnapshotMetadata(Collections2.transform(clients.values(),
  73             FrontendClientMetadataBuilder::build));
  74     }
  75
  76     private FrontendClientMetadataBuilder ensureClient(final ClientIdentifier id) {
  77         final FrontendClientMetadataBuilder existing = clients.get(id.getFrontendId());
  78         if (existing != null && id.equals(existing.getIdentifier())) {
  79             return existing;
  80         }
  81
  82         final FrontendClientMetadataBuilder client = new FrontendClientMetadataBuilder(id);
  83         final FrontendClientMetadataBuilder previous = clients.put(id.getFrontendId(), client);
  84         if (previous != null) {
  85             LOG.debug("{}: Replaced client {} with {}", shardName, previous, client);
  86         } else {
  87             LOG.debug("{}: Added client {}", shardName, client);
  88         }
  89         return client;
  90     }
  91
  92     @Override
  93     void onHistoryCreated(final LocalHistoryIdentifier historyId) {
  94         ensureClient(historyId.getClientId()).onHistoryCreated(historyId);
  95     }
  96
  97     @Override
  98     void onHistoryClosed(final LocalHistoryIdentifier historyId) {
  99         ensureClient(historyId.getClientId()).onHistoryClosed(historyId);
 100     }
 101
 102     @Override
 103     void onHistoryPurged(final LocalHistoryIdentifier historyId) {
 104         ensureClient(historyId.getClientId()).onHistoryPurged(historyId);
 105     }
 106
 107     @Override
 108     void onTransactionAborted(final TransactionIdentifier txId) {
 109         ensureClient(txId.getHistoryId().getClientId()).onTransactionAborted(txId);
 110     }
 111
 112     @Override
 113     void onTransactionCommitted(final TransactionIdentifier txId) {
 114         ensureClient(txId.getHistoryId().getClientId()).onTransactionCommitted(txId);
 115     }
 116
 117     @Override
 118     void onTransactionPurged(final TransactionIdentifier txId) {
 119         ensureClient(txId.getHistoryId().getClientId()).onTransactionPurged(txId);
 120     }
 121
 122     /**
 123      * Transform frontend metadata into an active leader state map.
 124      *
 125      * @return Leader frontend state
 126      */
 127     @Nonnull Map<FrontendIdentifier, LeaderFrontendState> toLeaderState(@Nonnull final Shard shard) {
 128         return new HashMap<>(Maps.transformValues(clients, meta -> meta.toLeaderState(shard)));
 129     }
 130 }