netconf/abstract-topology/src/main/java/org/opendaylight/netconf/topology/util/TopologyRoleChangeStrategy.java

   1 /*
   2  * Copyright (c) 2015 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
   9 package org.opendaylight.netconf.topology.util;
  10
  11 import java.util.Collection;
  12 import javax.annotation.Nonnull;
  13 import org.opendaylight.controller.md.sal.binding.api.ClusteredDataTreeChangeListener;
  14 import org.opendaylight.controller.md.sal.binding.api.DataBroker;
  15 import org.opendaylight.controller.md.sal.binding.api.DataObjectModification;
  16 import org.opendaylight.controller.md.sal.binding.api.DataTreeIdentifier;
  17 import org.opendaylight.controller.md.sal.binding.api.DataTreeModification;
  18 import org.opendaylight.controller.md.sal.common.api.clustering.CandidateAlreadyRegisteredException;
  19 import org.opendaylight.controller.md.sal.common.api.clustering.Entity;
  20 import org.opendaylight.controller.md.sal.common.api.clustering.EntityOwnershipCandidateRegistration;
  21 import org.opendaylight.controller.md.sal.common.api.clustering.EntityOwnershipChange;
  22 import org.opendaylight.controller.md.sal.common.api.clustering.EntityOwnershipListener;
  23 import org.opendaylight.controller.md.sal.common.api.clustering.EntityOwnershipListenerRegistration;
  24 import org.opendaylight.controller.md.sal.common.api.clustering.EntityOwnershipService;
  25 import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
  26 import org.opendaylight.netconf.topology.NodeListener;
  27 import org.opendaylight.netconf.topology.RoleChangeStrategy;
  28 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.NetworkTopology;
  29 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.NodeId;
  30 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.TopologyId;
  31 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.Topology;
  32 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.TopologyKey;
  33 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.topology.Node;
  34 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.topology.NodeKey;
  35 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  36 import org.opendaylight.yangtools.yang.binding.Identifier;
  37 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  38 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier.PathArgument;
  39 import org.slf4j.Logger;
  40 import org.slf4j.LoggerFactory;
  41
  42 public class TopologyRoleChangeStrategy implements RoleChangeStrategy, ClusteredDataTreeChangeListener<Node>, EntityOwnershipListener {
  43
  44     private static final Logger LOG = LoggerFactory.getLogger(TopologyRoleChangeStrategy.class);
  45
  46     private final DataBroker dataBroker;
  47
  48     private final EntityOwnershipService entityOwnershipService;
  49     private NodeListener ownershipCandidate;
  50     private final String entityType;
  51     // use topologyId as entityName
  52     private final Entity entity;
  53
  54     private EntityOwnershipCandidateRegistration candidateRegistration = null;
  55     private EntityOwnershipListenerRegistration ownershipListenerRegistration = null;
  56
  57     private ListenerRegistration<TopologyRoleChangeStrategy> datastoreListenerRegistration;
  58
  59     public TopologyRoleChangeStrategy(final DataBroker dataBroker,
  60                                       final EntityOwnershipService entityOwnershipService,
  61                                       final String entityType,
  62                                       final String entityName) {
  63         this.dataBroker = dataBroker;
  64         this.entityOwnershipService = entityOwnershipService;
  65         this.entityType = entityType;
  66         this.entity = new Entity(entityType, entityName);
  67
  68         datastoreListenerRegistration = null;
  69     }
  70
  71     @Override
  72     public void registerRoleCandidate(NodeListener electionCandidate) {
  73         LOG.warn("Registering candidate");
  74         ownershipCandidate = electionCandidate;
  75         try {
  76             if (candidateRegistration != null) {
  77                 unregisterRoleCandidate();
  78             }
  79             candidateRegistration = entityOwnershipService.registerCandidate(entity);
  80             ownershipListenerRegistration = entityOwnershipService.registerListener(entityType, this);
  81         } catch (CandidateAlreadyRegisteredException e) {
  82             LOG.error("Candidate already registered for election", e);
  83             throw new IllegalStateException("Candidate already registered for election", e);
  84         }
  85     }
  86
  87     @Override
  88     public void unregisterRoleCandidate() {
  89         candidateRegistration.close();
  90         candidateRegistration = null;
  91         ownershipListenerRegistration.close();
  92         ownershipListenerRegistration = null;
  93     }
  94
  95     @Override
  96     public boolean isCandidateRegistered() {
  97         return entityOwnershipService.isCandidateRegistered(entity);
  98     }
  99
 100     @Override
 101     public void onRoleChanged(RoleChangeDTO roleChangeDTO) {
 102         if (roleChangeDTO.isOwner()) {
 103             LOG.warn("Gained ownership of entity, registering datastore listener");
 104
 105             if (datastoreListenerRegistration == null) {
 106                 LOG.debug("Listener on path {}", createTopologyId(entityType).child(Node.class).getPathArguments());
 107                 datastoreListenerRegistration = dataBroker.registerDataTreeChangeListener(
 108                         new DataTreeIdentifier<>(LogicalDatastoreType.CONFIGURATION, createTopologyId(entityType).child(Node.class)), this);
 109             }
 110         } else if (datastoreListenerRegistration != null) {
 111             LOG.warn("No longer owner of entity, unregistering datastore listener");
 112             datastoreListenerRegistration.close();
 113             datastoreListenerRegistration = null;
 114         }
 115         ownershipCandidate.onRoleChanged(roleChangeDTO);
 116     }
 117
 118     @Override
 119     public void ownershipChanged(final EntityOwnershipChange ownershipChange) {
 120         onRoleChanged(new RoleChangeDTO(ownershipChange.wasOwner(), ownershipChange.isOwner(), ownershipChange.hasOwner()));
 121     }
 122
 123     @Override
 124     public void onDataTreeChanged(@Nonnull Collection<DataTreeModification<Node>> changes) {
 125         for (DataTreeModification<Node> change : changes) {
 126             final DataObjectModification<Node> rootNode = change.getRootNode();
 127             switch (rootNode.getModificationType()) {
 128                 case WRITE:
 129                     LOG.debug("Data was Created {}, {}", rootNode.getIdentifier(), rootNode.getDataAfter());
 130                     ownershipCandidate.onNodeCreated(getNodeId(rootNode.getIdentifier()), rootNode.getDataAfter());
 131                     break;
 132                 case SUBTREE_MODIFIED:
 133                     LOG.debug("Data was Updated {}, {}", rootNode.getIdentifier(), rootNode.getDataAfter());
 134                     ownershipCandidate.onNodeUpdated(getNodeId(rootNode.getIdentifier()), rootNode.getDataAfter());
 135                     break;
 136                 case DELETE:
 137                     LOG.debug("Data was Deleted {}", rootNode.getIdentifier());
 138                     ownershipCandidate.onNodeDeleted(getNodeId(rootNode.getIdentifier()));
 139             }
 140         }
 141     }
 142
 143     /**
 144      * Determines the Netconf Node Node ID, given the node's instance
 145      * identifier.
 146      *
 147      * @param pathArgument Node's path arument
 148      * @return     NodeId for the node
 149      */
 150     private NodeId getNodeId(final PathArgument pathArgument) {
 151         if (pathArgument instanceof InstanceIdentifier.IdentifiableItem<?, ?>) {
 152
 153             final Identifier key = ((InstanceIdentifier.IdentifiableItem) pathArgument).getKey();
 154             if(key instanceof NodeKey) {
 155                 return ((NodeKey) key).getNodeId();
 156             }
 157         }
 158         throw new IllegalStateException("Unable to create NodeId from: " + pathArgument);
 159     }
 160
 161     private static InstanceIdentifier<Topology> createTopologyId(final String topologyId) {
 162         final InstanceIdentifier<NetworkTopology> networkTopology = InstanceIdentifier.create(NetworkTopology.class);
 163         return networkTopology.child(Topology.class, new TopologyKey(new TopologyId(topologyId)));
 164     }
 165 }