Bug 4105: Add EntityOwnerDataChangeListener

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

diff --git a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/entityownership/EntityOwnerChangeListener.java b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/entityownership/EntityOwnerChangeListener.java
new file mode 100644 (file)
index 0000000..bf26163
--- /dev/null
+++ b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/entityownership/EntityOwnerChangeListener.java
@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2015 Brocade Communications Systems, Inc. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.controller.cluster.datastore.entityownership;
+
+import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_ID_QNAME;
+import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_OWNERS_PATH;
+import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_OWNER_NODE_ID;
+import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_QNAME;
+import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_TYPE_QNAME;
+import com.google.common.base.Objects;
+import com.google.common.base.Optional;
+import java.util.Collection;
+import java.util.Map.Entry;
+import org.opendaylight.controller.cluster.datastore.ShardDataTree;
+import org.opendaylight.controller.md.sal.common.api.clustering.Entity;
+import org.opendaylight.controller.md.sal.dom.api.DOMDataTreeChangeListener;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.controller.md.sal.clustering.entity.owners.rev150804.entity.owners.EntityType;
+import org.opendaylight.yangtools.yang.common.QName;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
+import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
+import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
+import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
+import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A DataChangeListener that listeners for entity owner changes and notifies the EntityOwnershipListenerSupport
+ * appropriately.
+ *
+ * @author Thomas Pantelis
+ */
+class EntityOwnerChangeListener implements DOMDataTreeChangeListener {
+    private static final Logger LOG = LoggerFactory.getLogger(EntityOwnerChangeListener.class);
+
+    private final String localMemberName;
+    private final EntityOwnershipListenerSupport listenerSupport;
+
+    EntityOwnerChangeListener(String localMemberName, EntityOwnershipListenerSupport listenerSupport) {
+        this.localMemberName = localMemberName;
+        this.listenerSupport = listenerSupport;
+    }
+
+    void init(ShardDataTree shardDataTree) {
+        shardDataTree.registerTreeChangeListener(YangInstanceIdentifier.builder(ENTITY_OWNERS_PATH).
+                node(EntityType.QNAME).node(EntityType.QNAME).node(ENTITY_QNAME).node(ENTITY_QNAME).build(), this);
+    }
+
+    @Override
+    public void onDataTreeChanged(Collection<DataTreeCandidate> changes) {
+        for(DataTreeCandidate change: changes) {
+            MapEntryNode entityNode = (MapEntryNode) change.getRootNode().getDataAfter().get();
+
+            LOG.debug("Entity node updated: {}", change.getRootPath());
+
+            String newOwner = extractOwner(entityNode);
+
+            String origOwner = null;
+            Optional<NormalizedNode<?, ?>> dataBefore = change.getRootNode().getDataBefore();
+            if(dataBefore.isPresent()) {
+                MapEntryNode origEntityNode = (MapEntryNode) change.getRootNode().getDataBefore().get();
+                origOwner = extractOwner(origEntityNode);
+            }
+
+            LOG.debug("New owner: {}, Original owner: {}", newOwner, origOwner);
+
+            boolean isOwner = Objects.equal(localMemberName, newOwner);
+            boolean wasOwner = Objects.equal(localMemberName, origOwner);
+            if(isOwner || wasOwner) {
+                Entity entity = createEntity(change.getRootPath());
+
+                LOG.debug("Calling notifyEntityOwnershipListeners: entity: {}, wasOwner: {}, isOwner: {}",
+                        entity, wasOwner, isOwner);
+
+                listenerSupport.notifyEntityOwnershipListeners(entity, wasOwner, isOwner);
+            }
+        }
+    }
+
+    private Entity createEntity(YangInstanceIdentifier entityPath) {
+        String entityType = null;
+        YangInstanceIdentifier entityId = null;
+        for(PathArgument pathArg: entityPath.getPathArguments()) {
+            if(pathArg instanceof NodeIdentifierWithPredicates) {
+                NodeIdentifierWithPredicates nodeKey = (NodeIdentifierWithPredicates) pathArg;
+                Entry<QName, Object> key = nodeKey.getKeyValues().entrySet().iterator().next();
+                if(ENTITY_TYPE_QNAME.equals(key.getKey())) {
+                    entityType = key.getValue().toString();
+                } else if(ENTITY_ID_QNAME.equals(key.getKey())) {
+                    entityId = (YangInstanceIdentifier) key.getValue();
+                }
+            }
+        }
+
+        return new Entity(entityType, entityId);
+    }
+
+    private String extractOwner(MapEntryNode entityNode) {
+        Optional<DataContainerChild<? extends PathArgument, ?>> ownerNode = entityNode.getChild(ENTITY_OWNER_NODE_ID);
+        return ownerNode.isPresent() ? (String) ownerNode.get().getValue() : null;
+    }
+}