Enable link functionality in GUI2 Topology View

Change-Id: I1b88080ecdf8c9b6f8a60af4832a12441186d508
diff --git a/web/gui2/src/main/webapp/app/view/topology/traffic.service.ts b/web/gui2/src/main/webapp/app/view/topology/traffic.service.ts
new file mode 100644
index 0000000..b6d2b85
--- /dev/null
+++ b/web/gui2/src/main/webapp/app/view/topology/traffic.service.ts
@@ -0,0 +1,90 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * 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.
+ */
+import { Injectable } from '@angular/core';
+import {LogService, WebSocketService} from 'gui2-fw-lib';
+import {ForceSvgComponent} from './layer/forcesvg/forcesvg.component';
+
+export enum TrafficType {
+    IDLE,
+    FLOWSTATSBYTES = 'flowStatsBytes',
+    PORTSTATSBITSEC = 'portStatsBitSec',
+    PORTSTATSPKTSEC = 'portStatsPktSec',
+}
+
+const ALL_TRAFFIC_TYPES = [
+    TrafficType.FLOWSTATSBYTES,
+    TrafficType.PORTSTATSBITSEC,
+    TrafficType.PORTSTATSPKTSEC
+];
+
+const ALL_TRAFFIC_MSGS = [
+    'Flow Stats (bytes)',
+    'Port Stats (bits / second)',
+    'Port Stats (packets / second)',
+];
+
+/**
+ * ONOS GUI -- Traffic Service Module.
+ */
+@Injectable({
+    providedIn: 'root'
+})
+export class TrafficService {
+    private handlers: string[] = [];
+    private openListener: any;
+
+    constructor(
+        protected log: LogService,
+        protected wss: WebSocketService
+    ) {
+        this.log.debug('TrafficService constructed');
+    }
+
+    init(force: ForceSvgComponent) {
+        this.wss.bindHandlers(new Map<string, (data) => void>([
+            ['topo2Highlights', (data) => {
+                  force.handleHighlights(data.devices, data.hosts, data.links);
+                }
+            ]
+        ]));
+
+        this.handlers.push('topo2Highlights');
+
+        // in case we fail over to a new server,
+        // listen for wsock-open events
+        this.openListener = this.wss.addOpenListener(() => this.wsOpen);
+
+        // tell the server we are ready to receive topology events
+        this.wss.sendEvent('topo2RequestAllTraffic', {
+            trafficType: TrafficType.FLOWSTATSBYTES
+        });
+        this.log.debug('Topo2Traffic: Show All Traffic');
+    }
+
+    destroy() {
+        this.wss.sendEvent('topo2CancelTraffic', {});
+        this.wss.unbindHandlers(this.handlers);
+        this.log.debug('Traffic monitoring canceled');
+    }
+
+    wsOpen(host: string, url: string) {
+        this.log.debug('topo2RequestAllTraffic: WSopen - cluster node:', host, 'URL:', url);
+        // tell the server we are ready to receive topo events
+        this.wss.sendEvent('topo2RequestAllTraffic', {
+            trafficType: TrafficType.FLOWSTATSBYTES
+        });
+    }
+}