fix: session start when page appear without page hide (#53)

Co-authored-by: xiaoweii <xiaoweii@amazom.com>

Author: zhu-xiaowei

src/tracker/Session.ts

@@ -18,6 +18,7 @@ export class Session {
 	startTime: number;
 	sessionIndex: number;
 	pauseTime: number;
+	isRecorded = false;
 
 	static createSession(uniqueId: string, sessionIndex: number): Session {
 		return new Session(
@@ -40,7 +41,7 @@ export class Session {
 	}
 
 	isNewSession(): boolean {
-		return this.pauseTime === undefined;
+		return this.pauseTime === undefined && !this.isRecorded;
 	}
 
 	getDuration(): number {
@@ -61,8 +62,9 @@ export class Session {
 		}
 		if (session !== null) {
 			if (
+				session.pauseTime === undefined ||
 				new Date().getTime() - session.pauseTime <
-				context.configuration.sessionTimeoutDuration
+					context.configuration.sessionTimeoutDuration
 			) {
 				return session;
 			} else {

src/tracker/SessionTracker.ts

@@ -72,6 +72,7 @@ export class SessionTracker extends BaseTracker {
 			pageViewTracker.setIsEntrances();
 			StorageUtil.clearPageInfo();
 			this.provider.record({ name: Event.PresetEvent.SESSION_START });
+			this.session.isRecorded = true;
 			if (!isFirstTime) {
 				pageViewTracker.onPageChange();
 			}

test/tracker/SessionTracker.test.ts

@@ -93,7 +93,31 @@ describe('SessionTracker test', () => {
 		const session = sessionTracker.session;
 		expect(session.sessionIndex).toBe(1);
 		expect(session.sessionId).not.toBeUndefined();
-		expect(session.isNewSession()).toBeTruthy();
+		expect(session.isNewSession()).toBeFalsy();
+	});
+
+	test('test page appear without page hide will not record session start twice', () => {
+		const pageAppearMock = jest.spyOn(sessionTracker, 'onPageAppear');
+		sessionTracker.setUp();
+		expect(pageAppearMock).toBeCalledWith(true);
+		expect(recordMethodMock).toBeCalledWith({
+			name: Event.PresetEvent.SESSION_START,
+		});
+		const session = sessionTracker.session;
+		expect(session.sessionIndex).toBe(1);
+		expect(session.sessionId).not.toBeUndefined();
+		expect(session.isRecorded).toBeTruthy();
+		expect(session.isNewSession()).toBeFalsy();
+
+		sessionTracker.onPageAppear(false);
+		sessionTracker.onPageAppear(false);
+		expect(pageAppearMock).toBeCalledWith(false);
+		const allCalls = recordMethodMock.mock.calls;
+		const sessionStartCalls = allCalls.filter((call: [any]) => {
+			const [arg] = call;
+			return arg && arg.name === Event.PresetEvent.SESSION_START;
+		});
+		expect(sessionStartCalls.length).toBe(1);
 	});
 
 	test('test first open and session start event has the same sessionId', () => {