fix(sessions): Do not track sessions if not enabled (#3686)

Fixes #3685

The patch updates the @sentry/core baseClient to not send sessions
to Sentry if it is disabled. This makes sessions match the behaviour
of events and integrations (both of which get disabled when the
enabled option is set to false).

Author: AbhiPrasad

packages/core/src/baseclient.ts

@@ -152,6 +152,11 @@ export abstract class BaseClient<B extends Backend, O extends Options> implement
    * @inheritDoc
    */
   public captureSession(session: Session): void {
+    if (!this._isEnabled()) {
+      logger.warn('SDK not enabled, will not capture session.');
+      return;
+    }
+
     if (!(typeof session.release === 'string')) {
       logger.warn('Discarded session because of missing or non-string release');
     } else {
@@ -485,7 +490,7 @@ export abstract class BaseClient<B extends Backend, O extends Options> implement
     const { beforeSend, sampleRate } = this.getOptions();
 
     if (!this._isEnabled()) {
-      return SyncPromise.reject(new SentryError('SDK not enabled, will not send event.'));
+      return SyncPromise.reject(new SentryError('SDK not enabled, will not capture event.'));
     }
 
     const isTransaction = event.type === 'transaction';

packages/core/test/lib/base.test.ts

@@ -1,4 +1,4 @@
-import { Hub, Scope } from '@sentry/hub';
+import { Hub, Scope, Session } from '@sentry/hub';
 import { Event, Severity, Span } from '@sentry/types';
 import { logger, SentryError, SyncPromise } from '@sentry/utils';
 
@@ -964,4 +964,22 @@ describe('BaseClient', () => {
       ]);
     });
   });
+
+  describe('captureSession()', () => {
+    test('sends sessions to the backend', () => {
+      expect.assertions(1);
+      const client = new TestClient({ dsn: PUBLIC_DSN });
+      const session = new Session({ release: 'test' });
+      client.captureSession(session);
+      expect(TestBackend.instance!.session).toEqual(session);
+    });
+
+    test('skips when disabled', () => {
+      expect.assertions(1);
+      const client = new TestClient({ enabled: false, dsn: PUBLIC_DSN });
+      const session = new Session({ release: 'test' });
+      client.captureSession(session);
+      expect(TestBackend.instance!.session).toBeUndefined();
+    });
+  });
 });

packages/core/test/mocks/backend.ts

@@ -1,3 +1,4 @@
+import { Session } from '@sentry/hub';
 import { Event, Options, Severity, Transport } from '@sentry/types';
 import { SyncPromise } from '@sentry/utils';
 
@@ -14,6 +15,7 @@ export class TestBackend extends BaseBackend<TestOptions> {
   public static sendEventCalled?: (event: Event) => void;
 
   public event?: Event;
+  public session?: Session;
 
   public constructor(protected readonly _options: TestOptions) {
     super(_options);
@@ -50,6 +52,10 @@ export class TestBackend extends BaseBackend<TestOptions> {
     TestBackend.sendEventCalled && TestBackend.sendEventCalled(event);
   }
 
+  public sendSession(session: Session): void {
+    this.session = session;
+  }
+
   protected _setupTransport(): Transport {
     if (!this._options.dsn) {
       // We return the noop transport here in case there is no Dsn.