de9f7aca39aa45180603f40bfb32cee4ae3a21c9
[netconf.git] / opendaylight / 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 String entityName;
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.entityName = 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(new Entity(entityType, entityName));
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 void onRoleChanged(RoleChangeDTO roleChangeDTO) {
97         if (roleChangeDTO.isOwner()) {
98             LOG.warn("Gained ownership of entity, registering datastore listener");
99
100             if (datastoreListenerRegistration == null) {
101                 LOG.debug("Listener on path {}", createTopologyId(entityType).child(Node.class).getPathArguments());
102                 datastoreListenerRegistration = dataBroker.registerDataTreeChangeListener(
103                         new DataTreeIdentifier<>(LogicalDatastoreType.CONFIGURATION, createTopologyId(entityType).child(Node.class)), this);
104             }
105         } else if (datastoreListenerRegistration != null) {
106             LOG.warn("No longer owner of entity, unregistering datastore listener");
107             datastoreListenerRegistration.close();
108             datastoreListenerRegistration = null;
109         }
110         ownershipCandidate.onRoleChanged(roleChangeDTO);
111     }
112
113     @Override
114     public void ownershipChanged(final EntityOwnershipChange ownershipChange) {
115         onRoleChanged(new RoleChangeDTO(ownershipChange.wasOwner(), ownershipChange.isOwner(), ownershipChange.hasOwner()));
116     }
117
118     @Override
119     public void onDataTreeChanged(@Nonnull Collection<DataTreeModification<Node>> changes) {
120         for (DataTreeModification<Node> change : changes) {
121             final DataObjectModification<Node> rootNode = change.getRootNode();
122             switch (rootNode.getModificationType()) {
123                 case WRITE:
124                     LOG.debug("Data was Created {}, {}", rootNode.getIdentifier(), rootNode.getDataAfter());
125                     ownershipCandidate.onNodeCreated(getNodeId(rootNode.getIdentifier()), rootNode.getDataAfter());
126                     break;
127                 case SUBTREE_MODIFIED:
128                     LOG.debug("Data was Updated {}, {}", rootNode.getIdentifier(), rootNode.getDataAfter());
129                     ownershipCandidate.onNodeUpdated(getNodeId(rootNode.getIdentifier()), rootNode.getDataAfter());
130                     break;
131                 case DELETE:
132                     LOG.debug("Data was Deleted {}", rootNode.getIdentifier());
133                     ownershipCandidate.onNodeDeleted(getNodeId(rootNode.getIdentifier()));
134             }
135         }
136     }
137
138     /**
139      * Determines the Netconf Node Node ID, given the node's instance
140      * identifier.
141      *
142      * @param pathArgument Node's path arument
143      * @return     NodeId for the node
144      */
145     private NodeId getNodeId(final PathArgument pathArgument) {
146         if (pathArgument instanceof InstanceIdentifier.IdentifiableItem<?, ?>) {
147
148             final Identifier key = ((InstanceIdentifier.IdentifiableItem) pathArgument).getKey();
149             if(key instanceof NodeKey) {
150                 return ((NodeKey) key).getNodeId();
151             }
152         }
153         throw new IllegalStateException("Unable to create NodeId from: " + pathArgument);
154     }
155
156     private static InstanceIdentifier<Topology> createTopologyId(final String topologyId) {
157         final InstanceIdentifier<NetworkTopology> networkTopology = InstanceIdentifier.create(NetworkTopology.class);
158         return networkTopology.child(Topology.class, new TopologyKey(new TopologyId(topologyId)));
159     }
160 }