New ComponentConfigStore that uses a ConsistentMap configured with sequential consistency

Change-Id: Ic24e6c59b1cec2b3b8ee8690cd8e4dfaec5ed476

+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.store.cfg;
+
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.apache.felix.scr.annotations.Service;
+import org.onosproject.cfg.ComponentConfigEvent;
+import org.onosproject.cfg.ComponentConfigStore;
+import org.onosproject.cfg.ComponentConfigStoreDelegate;
+import org.onosproject.store.AbstractStore;
+import org.onosproject.store.serializers.KryoNamespaces;
+import org.onosproject.store.service.ConsistentMap;
+import org.onosproject.store.service.MapEvent;
+import org.onosproject.store.service.MapEventListener;
+import org.onosproject.store.service.Serializer;
+import org.onosproject.store.service.StorageService;
+import org.slf4j.Logger;
+
+import static org.onosproject.cfg.ComponentConfigEvent.Type.PROPERTY_SET;
+import static org.onosproject.cfg.ComponentConfigEvent.Type.PROPERTY_UNSET;
+import static org.onosproject.store.service.MapEvent.Type.INSERT;
+import static org.onosproject.store.service.MapEvent.Type.REMOVE;
+import static org.onosproject.store.service.MapEvent.Type.UPDATE;
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Manages inventory of component configurations in a distributed data store
+ * that provides strong sequential consistency guarantees.
+ */
+@Component(immediate = true, enabled = true)
+@Service
+public class DistributedComponentConfigStore
+        extends AbstractStore<ComponentConfigEvent, ComponentConfigStoreDelegate>
+        implements ComponentConfigStore {
+
+    private static final String SEP = "#";
+
+    private final Logger log = getLogger(getClass());
+
+    private ConsistentMap<String, String> properties;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected StorageService storageService;
+
+    InternalPropertiesListener propertiesListener = new InternalPropertiesListener();
+
+    @Activate
+    public void activate() {
+        properties = storageService.<String, String>consistentMapBuilder()
+                .withName("onos-component-cfg")
+                .withSerializer(Serializer.using(KryoNamespaces.API))
+                .withRelaxedReadConsistency()
+                .build();
+
+        properties.addListener(propertiesListener);
+        log.info("Started");
+    }
+
+    @Deactivate
+    public void deactivate() {
+        properties.removeListener(propertiesListener);
+        log.info("Stopped");
+    }
+
+    @Override
+    public void setProperty(String componentName, String name, String value) {
+        properties.put(key(componentName, name), value);
+
+    }
+
+    @Override
+    public void unsetProperty(String componentName, String name) {
+        properties.remove(key(componentName, name));
+    }
+
+    /**
+     * Listener to component configuration properties distributed map changes.
+     */
+    private final class InternalPropertiesListener
+            implements MapEventListener<String, String> {
+
+        @Override
+        public void event(MapEvent<String, String> event) {
+            String[] keys = event.key().split(SEP);
+            if (event.type() == INSERT || event.type() == UPDATE) {
+                String value = event.newValue().value();
+                delegate.notify(new ComponentConfigEvent(PROPERTY_SET, keys[0], keys[1], value));
+            } else if (event.type() == REMOVE) {
+                delegate.notify(new ComponentConfigEvent(PROPERTY_UNSET, keys[0], keys[1], null));
+            }
+        }
+    }
+
+    // Generates a key from component name and property name.
+    private String key(String componentName, String name) {
+        return componentName + SEP + name;
+    }
+}

@@ -44,7 +44,7 @@ import static org.slf4j.LoggerFactory.getLogger;
  * Manages inventory of component configurations in a distributed data store
  * that uses optimistic replication and gossip based anti-entropy techniques.
  */
-@Component(immediate = true)
+@Component(immediate = true, enabled = false)
 @Service
 public class GossipComponentConfigStore
         extends AbstractStore<ComponentConfigEvent, ComponentConfigStoreDelegate>