Added test for app insights (#1522)

* Added test

* Added test for app insights

* Updated test name

Author: ChrisS1512

src/test/unit/modules/appinsights/appinsights.test.ts

@@ -0,0 +1,82 @@
+const mockTrackTrace = jest.fn();
+const mockSetSendLiveMetrics = jest.fn().mockReturnThis();
+const mockStart = jest.fn().mockReturnThis();
+
+jest.mock('applicationinsights', () => {
+    return {
+        setup: jest.fn(() => ({
+            setSendLiveMetrics: mockSetSendLiveMetrics,
+            start: mockStart,
+        })),
+        defaultClient: {
+            context: {
+                tags: {},
+                keys: {
+                    cloudRole: 'undefined-frontend',
+                },
+            },
+            trackTrace: mockTrackTrace,
+        },
+    };
+});
+
+import * as appInsights from 'applicationinsights';
+import { AppInsights } from '../../../../main/modules/appinsights';
+
+jest.mock('config', () => ({
+    get: jest.fn(() => {
+        return 'CONFIG_CONNECTION_STRING';
+    }),
+}));
+
+describe('App Insights', () => {
+    beforeEach(() => {
+        jest.clearAllMocks();
+        delete process.env.APP_INSIGHTS_CONNECTION_STRING;
+        appInsights.defaultClient.context.tags = {};
+    });
+
+    it('Uses environment variable for connection string', () => {
+        process.env.APP_INSIGHTS_CONNECTION_STRING = 'ENV_CONNECTION_STRING';
+        const appInsightsLibrary = new AppInsights();
+        appInsightsLibrary.enable();
+
+        expect(appInsights.setup).toHaveBeenCalledWith('ENV_CONNECTION_STRING');
+        expect(mockSetSendLiveMetrics).toHaveBeenCalledWith(true);
+        expect(mockStart).toHaveBeenCalled();
+        expect(appInsights.defaultClient.context.tags[appInsights.defaultClient.context.keys.cloudRole]).toBe(
+            'pip-frontend'
+        );
+        expect(mockTrackTrace).toHaveBeenCalledWith({ message: 'App insights activated' });
+    });
+
+    it('Uses config for connection string if env not set', () => {
+        const appInsightsLibrary = new AppInsights();
+        appInsightsLibrary.enable();
+
+        expect(appInsights.setup).toHaveBeenCalledWith('CONFIG_CONNECTION_STRING');
+        expect(mockSetSendLiveMetrics).toHaveBeenCalledWith(true);
+        expect(mockStart).toHaveBeenCalled();
+        expect(appInsights.defaultClient.context.tags[appInsights.defaultClient.context.keys.cloudRole]).toBe(
+            'pip-frontend'
+        );
+        expect(mockTrackTrace).toHaveBeenCalledWith({ message: 'App insights activated' });
+    });
+
+    it('Does nothing if no connection string is available', async () => {
+        jest.resetModules();
+        jest.doMock('config', () => ({
+            get: jest.fn(() => undefined),
+        }));
+        delete process.env.APP_INSIGHTS_CONNECTION_STRING;
+
+        const { AppInsights: AppInsightsNoConfig } = await import('../../../../main/modules/appinsights');
+        const appInsightsLibrary = new AppInsightsNoConfig();
+        appInsightsLibrary.enable();
+
+        expect(appInsights.setup).not.toHaveBeenCalled();
+        expect(mockSetSendLiveMetrics).not.toHaveBeenCalled();
+        expect(mockStart).not.toHaveBeenCalled();
+        expect(mockTrackTrace).not.toHaveBeenCalled();
+    });
+});