opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/entityownership/EntityOwnerChangeListener.java

   1 /*
   2  * Copyright (c) 2015 Brocade Communications 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.entityownership;
   9
  10 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_OWNERS_PATH;
  11 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_QNAME;
  12 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.createEntity;
  13 import com.google.common.base.Objects;
  14 import com.google.common.base.Optional;
  15 import java.util.Collection;
  16 import org.opendaylight.controller.cluster.datastore.ShardDataTree;
  17 import org.opendaylight.controller.md.sal.common.api.clustering.Entity;
  18 import org.opendaylight.controller.md.sal.dom.api.DOMDataTreeChangeListener;
  19 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.controller.md.sal.clustering.entity.owners.rev150804.entity.owners.EntityType;
  20 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  21 import org.opendaylight.yangtools.yang.data.api.schema.LeafNode;
  22 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  23 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  24 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidateNode;
  25 import org.slf4j.Logger;
  26 import org.slf4j.LoggerFactory;
  27
  28 /**
  29  * Listens for entity owner changes and notifies the EntityOwnershipListenerSupport appropriately.
  30  *
  31  * @author Thomas Pantelis
  32  */
  33 class EntityOwnerChangeListener implements DOMDataTreeChangeListener {
  34     private static final Logger LOG = LoggerFactory.getLogger(EntityOwnerChangeListener.class);
  35
  36     private final String localMemberName;
  37     private final EntityOwnershipListenerSupport listenerSupport;
  38
  39     EntityOwnerChangeListener(String localMemberName, EntityOwnershipListenerSupport listenerSupport) {
  40         this.localMemberName = localMemberName;
  41         this.listenerSupport = listenerSupport;
  42     }
  43
  44     void init(ShardDataTree shardDataTree) {
  45         shardDataTree.registerTreeChangeListener(YangInstanceIdentifier.builder(ENTITY_OWNERS_PATH).
  46                 node(EntityType.QNAME).node(EntityType.QNAME).node(ENTITY_QNAME).node(ENTITY_QNAME).node(EntityOwnersModel.ENTITY_OWNER_QNAME).build(), this);
  47     }
  48
  49     @Override
  50     public void onDataTreeChanged(Collection<DataTreeCandidate> changes) {
  51         for(DataTreeCandidate change: changes) {
  52             DataTreeCandidateNode changeRoot = change.getRootNode();
  53             LeafNode<?> ownerLeaf = (LeafNode<?>) changeRoot.getDataAfter().get();
  54
  55             LOG.debug("{}: Entity node changed: {}, {}", logId(), changeRoot.getModificationType(), change.getRootPath());
  56
  57             String newOwner = extractOwner(ownerLeaf);
  58
  59             String origOwner = null;
  60             Optional<NormalizedNode<?, ?>> dataBefore = changeRoot.getDataBefore();
  61             if(dataBefore.isPresent()) {
  62                 origOwner = extractOwner((LeafNode<?>) changeRoot.getDataBefore().get());
  63             }
  64
  65             LOG.debug("{}: New owner: {}, Original owner: {}", logId(), newOwner, origOwner);
  66
  67             if(!Objects.equal(origOwner, newOwner)) {
  68                 boolean isOwner = Objects.equal(localMemberName, newOwner);
  69                 boolean wasOwner = Objects.equal(localMemberName, origOwner);
  70                 boolean hasOwner = newOwner != null && !newOwner.toString().isEmpty();
  71
  72                 Entity entity = createEntity(change.getRootPath());
  73
  74                 LOG.debug("{}: Calling notifyEntityOwnershipListeners: entity: {}, wasOwner: {}, isOwner: {}, hasOwner: {}",
  75                         logId(), entity, wasOwner, isOwner, hasOwner);
  76
  77                 listenerSupport.notifyEntityOwnershipListeners(entity, wasOwner, isOwner, hasOwner);
  78             }
  79         }
  80     }
  81
  82     private String extractOwner(LeafNode<?> ownerLeaf) {
  83         Object value = ownerLeaf.getValue();
  84         return value != null ? value.toString() : null;
  85     }
  86
  87     private String logId() {
  88         return listenerSupport.getLogId();
  89     }
  90 }