[CORD-2869] Adding service status dropdown

Change-Id: I8faa6d96f202fc097cc12df87e1825d7dff2852f
diff --git a/src/app/core/service-status/service-status.ts b/src/app/core/service-status/service-status.ts
new file mode 100644
index 0000000..05ac971
--- /dev/null
+++ b/src/app/core/service-status/service-status.ts
@@ -0,0 +1,74 @@
+
+/*
+ * Copyright 2017-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 {IXosAppConfig} from '../../../index';
+import IHttpPromise = angular.IHttpPromise;
+
+interface IXosServiceStatus {
+  name: string;
+  state: 'load' | 'unload' | 'present';
+  version: string;
+}
+
+interface IXosServiceStatusResponse {
+  model_output: string;
+  model_status: number;
+  services: IXosServiceStatus[];
+}
+
+class XosServiceStatusController {
+
+  static $inject = [
+    '$log',
+    '$http',
+    '$interval',
+    'AppConfig'
+  ];
+
+  public services: IXosServiceStatus[] = [];
+  public error: boolean;
+  public loaded: boolean = false;
+
+  constructor (
+    private $log: angular.ILogService,
+    private $http: angular.IHttpService,
+    private $interval: ng.IIntervalService,
+    private AppConfig: IXosAppConfig,
+  ) {
+    this.$interval(() => {
+      this.getServiceStatus()
+        .then(res => {
+          this.services = res.data.services;
+          this.loaded = true;
+        })
+        .catch(e => {
+          this.error = true;
+          this.$log.error(`[XosServiceStatus] Cannot read status from the backend`, e);
+        });
+    }, 10 * 1000);
+  }
+
+  private getServiceStatus(): IHttpPromise<IXosServiceStatusResponse> {
+    return this.$http.get(`${this.AppConfig.apiEndpoint}/dynamicload/load_status`);
+  }
+}
+
+export const xosServiceStatus: angular.IComponentOptions = {
+  template: require('./service-status.html'),
+  controllerAs: 'vm',
+  controller: XosServiceStatusController,
+};