ref(angular): Add transaction source for Angular Router (#5382)

Add the transaction name source annotation to the Angular SDK. Since the Angular SDK currently does not parameterize URLs, we only assign `'url'` as the transaction name source. We're revisiting parameterization in Angular in a follow up PR.

Additionally, add a two tests to cover this change (might be more relevant once we add parameterization).

packages/angular/src/tracing.ts

@@ -32,6 +32,7 @@ export function routingInstrumentation(
     customStartTransaction({
       name: global.location.pathname,
       op: 'pageload',
+      metadata: { source: 'url' },
     });
   }
 }
@@ -77,6 +78,7 @@ export class TraceService implements OnDestroy {
         activeTransaction = stashedStartTransaction({
           name: strippedUrl,
           op: 'navigation',
+          metadata: { source: 'url' },
         });
       }
 

packages/angular/test/tracing.test.ts

@@ -0,0 +1,47 @@
+import { NavigationStart, Router, RouterEvent } from '@angular/router';
+import { Subject } from 'rxjs';
+
+import { instrumentAngularRouting, TraceService } from '../src/index';
+
+describe('Angular Tracing', () => {
+  const startTransaction = jest.fn();
+  describe('instrumentAngularRouting', () => {
+    it('should attach the transaction source on the pageload transaction', () => {
+      instrumentAngularRouting(startTransaction);
+      expect(startTransaction).toHaveBeenCalledWith({
+        name: '/',
+        op: 'pageload',
+        metadata: { source: 'url' },
+      });
+    });
+  });
+
+  describe('TraceService', () => {
+    let traceService: TraceService;
+    const routerEvents$: Subject<RouterEvent> = new Subject();
+
+    beforeAll(() => instrumentAngularRouting(startTransaction));
+    beforeEach(() => {
+      jest.resetAllMocks();
+
+      traceService = new TraceService({
+        events: routerEvents$,
+      } as unknown as Router);
+    });
+
+    afterEach(() => {
+      traceService.ngOnDestroy();
+    });
+
+    it('attaches the transaction source on a navigation change', () => {
+      routerEvents$.next(new NavigationStart(0, 'user/123/credentials'));
+
+      expect(startTransaction).toHaveBeenCalledTimes(1);
+      expect(startTransaction).toHaveBeenCalledWith({
+        name: 'user/123/credentials',
+        op: 'navigation',
+        metadata: { source: 'url' },
+      });
+    });
+  });
+});