diff --git a/src/app/datasources/websocket/global.spec.ts b/src/app/datasources/websocket/global.spec.ts
new file mode 100644
index 0000000..7adaf07
--- /dev/null
+++ b/src/app/datasources/websocket/global.spec.ts
@@ -0,0 +1,184 @@
+/*
+ * 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 * as angular from 'angular';
+import 'angular-mocks';
+import {IWSEvent, IWSEventService, WebSocketEvent} from './global';
+
+const MockAppCfg = {
+  apiEndpoint: 'http://xos-test:3000/api',
+  websocketClient: 'http://xos-test:3000'
+};
+
+class MockSocket {
+  private cbs = {};
+
+  public on(event: string, cb: any) {
+    this.cbs[event] = cb;
+  }
+
+  public send(evt: string, data: any) {
+    const cb = this.cbs[evt];
+    cb(data);
+  }
+
+  public clean() {
+    this.cbs = {};
+  }
+}
+
+describe('The WebSocket service', () => {
+
+  let service, observable, mockWS;
+
+  beforeEach(() => {
+
+    mockWS = new MockSocket();
+
+    angular
+      .module('WebSocketEvent', [])
+      .service('WebSocket', WebSocketEvent)
+      .constant('AppConfig', MockAppCfg)
+      .value('SocketIo', {socket: mockWS});
+
+    angular.mock.module('WebSocketEvent');
+  });
+
+  beforeEach(angular.mock.inject((
+    WebSocket: IWSEventService
+  ) => {
+    service = WebSocket;
+    observable = service['_events'];
+
+    spyOn(observable, 'next');
+  }));
+
+  afterEach(() => {
+    mockWS.clean();
+    observable.next.calls.reset();
+  });
+
+  it('should have a list method', () => {
+    expect(service.list).toBeDefined();
+  });
+
+  describe('the update event', () => {
+    it('should update the base class', () => {
+      const data: IWSEvent = {
+        model: 'Test',
+        msg: {
+          pk: 1,
+          changed_fields: ['name'],
+          object: {}
+        }
+      };
+      mockWS.send('update', data);
+      expect(observable.next).toHaveBeenCalledWith(data);
+      expect(observable.next.calls.count()).toBe(1);
+    });
+
+    it('should not update the class if the changed_fields are not useful to the UI', () => {
+      const data: IWSEvent = {
+        model: 'Test',
+        msg: {
+          pk: 1,
+          changed_fields: ['created', 'updated', 'backend_register', 'backend_status', 'policy_status'],
+          object: {}
+        }
+      };
+      mockWS.send('update', data);
+      expect(observable.next).not.toHaveBeenCalled();
+    });
+
+    it('should update parent classes (if any)', () => {
+      const data: IWSEvent = {
+        model: 'ONOSApp',
+        msg: {
+          pk: 1,
+          changed_fields: ['name'],
+          object: {
+            class_names: 'ONOSApp,ONOSApp_decl,ServiceInstance,XOSBase,Model,PlModelMixIn,AttributeMixin,object'
+          }
+        }
+      };
+      mockWS.send('update', data);
+      expect(observable.next).toHaveBeenCalledWith(data);
+      const siEvent = data;
+      siEvent.model = 'ServiceInstance';
+      siEvent.skip_notification = true;
+      expect(observable.next).toHaveBeenCalledWith(siEvent);
+      expect(observable.next.calls.count()).toBe(2);
+    });
+  });
+
+  describe('the remove event', () => {
+    it('should trigger the remove event', () => {
+      const data: IWSEvent = {
+        model: 'Test',
+        msg: {
+          pk: 1,
+          changed_fields: [],
+          object: {}
+        },
+      };
+      mockWS.send('remove', data);
+      expect(observable.next).toHaveBeenCalledWith(data);
+    });
+
+    it('should update parent classes (if any)', () => {
+      const data: IWSEvent = {
+        model: 'ONOSApp',
+        msg: {
+          pk: 1,
+          changed_fields: ['name'],
+          object: {
+            class_names: 'ONOSApp,ONOSApp_decl,ServiceInstance,XOSBase,Model,PlModelMixIn,AttributeMixin,object'
+          }
+        }
+      };
+      mockWS.send('remove', data);
+      expect(observable.next).toHaveBeenCalledWith(data);
+      const siEvent = data;
+      siEvent.model = 'ServiceInstance';
+      siEvent.skip_notification = true;
+      expect(observable.next).toHaveBeenCalledWith(siEvent);
+      expect(observable.next.calls.count()).toBe(2);
+    });
+
+    it('should update derived class if the original is _decl', () => {
+      const data: IWSEvent = {
+        model: 'ONOSApp_decl',
+        msg: {
+          pk: 1,
+          changed_fields: ['name'],
+          object: {
+            class_names: 'ONOSApp_decl,ServiceInstance,XOSBase,Model,PlModelMixIn,AttributeMixin,object'
+          }
+        }
+      };
+      mockWS.send('remove', data);
+
+      const nextData = angular.copy(data);
+      nextData.model = 'ONOSApp';
+      expect(observable.next).toHaveBeenCalledWith(nextData);
+      const declEvent = nextData;
+      declEvent.model = 'ServiceInstance';
+      declEvent.skip_notification = true;
+      expect(observable.next).toHaveBeenCalledWith(declEvent);
+      expect(observable.next.calls.count()).toBe(2);
+    });
+  });
+});