ONOS-2690: Register a device as resource when it is added

Change-Id: I37f931665e06cb2415d569e61e8c6592faea485a

+/*
+ * Copyright 2015 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.net.newresource.impl;
+
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.device.DeviceEvent;
+import org.onosproject.net.device.DeviceListener;
+import org.onosproject.net.newresource.ResourceAdminService;
+import org.onosproject.net.newresource.ResourcePath;
+
+import java.util.concurrent.ExecutorService;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * An implementation of DeviceListener registering devices as resources.
+ */
+final class ResourceDeviceListener implements DeviceListener {
+
+    private final ResourceAdminService adminService;
+    private final ExecutorService executor;
+
+    /**
+     * Creates an instance with the specified ResourceAdminService and ExecutorService.
+     *
+     * @param adminService instance invoked to register resources
+     * @param executor executor used for processing resource registration
+     */
+    ResourceDeviceListener(ResourceAdminService adminService, ExecutorService executor) {
+        this.adminService = checkNotNull(adminService);
+        this.executor = checkNotNull(executor);
+    }
+
+    @Override
+    public void event(DeviceEvent event) {
+        Device device = event.subject();
+        switch (event.type()) {
+            case DEVICE_ADDED:
+                registerDeviceResource(device);
+                break;
+            default:
+                break;
+        }
+    }
+
+    private void registerDeviceResource(Device device) {
+        DeviceId deviceId = device.id();
+        executor.submit(() -> adminService.registerResources(new ResourcePath(ResourcePath.ROOT, deviceId)));
+    }
+}

@@ -21,6 +21,8 @@ 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.onosproject.net.device.DeviceListener;
+import org.onosproject.net.device.DeviceService;
 import org.onosproject.net.link.LinkListener;
 import org.onosproject.net.link.LinkService;
 import org.onosproject.net.newresource.ResourceAdminService;
@@ -41,20 +43,27 @@ public final class ResourceRegistrar {
     protected ResourceAdminService adminService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected DeviceService deviceService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected LinkService linkService;
 
+    private DeviceListener deviceListener;
     private LinkListener linkListener;
     private final ExecutorService executor =
             Executors.newSingleThreadExecutor(groupedThreads("onos/resource", "registrar"));
 
     @Activate
     public void activate() {
+        deviceListener = new ResourceDeviceListener(adminService, executor);
+        deviceService.addListener(deviceListener);
         linkListener = new ResourceLinkListener(adminService, executor);
         linkService.addListener(linkListener);
     }
 
     @Deactivate
     public void deactivate() {
+        deviceService.removeListener(deviceListener);
         linkService.removeListener(linkListener);
     }
 }