ref(replay): Sessions don't need to be sampled when fetched

Author: mydea

Diff for: packages/replay/src/session/fetchSession.ts

@@ -1,11 +1,10 @@
 import { REPLAY_SESSION_KEY, WINDOW } from '../constants';
-import { SampleRates } from '../types';
-import { makeSession, sampleSession, Session } from './Session';
+import { makeSession, Session } from './Session';
 
 /**
  * Fetches a session from storage
  */
-export function fetchSession({ sessionSampleRate, errorSampleRate }: SampleRates): Session | null {
+export function fetchSession(): Session | null {
   const hasSessionStorage = 'sessionStorage' in WINDOW;
 
   if (!hasSessionStorage) {
@@ -20,10 +19,9 @@ export function fetchSession({ sessionSampleRate, errorSampleRate }: SampleRates
       return null;
     }
 
-    const sessionObj = JSON.parse(sessionStringFromStorage) as Partial<Session>;
-    const sampled = sampleSession(sessionObj.sampled, sessionSampleRate, errorSampleRate);
+    const sessionObj = JSON.parse(sessionStringFromStorage) as Session;
 
-    return makeSession({ ...sessionObj, sampled });
+    return makeSession(sessionObj);
   } catch {
     return null;
   }

Diff for: packages/replay/src/session/getSession.ts

@@ -29,7 +29,7 @@ export function getSession({
   errorSampleRate,
 }: GetSessionParams): { type: 'new' | 'saved'; session: Session } {
   // If session exists and is passed, use it instead of always hitting session storage
-  const session = currentSession || (stickySession && fetchSession({ sessionSampleRate, errorSampleRate }));
+  const session = currentSession || (stickySession && fetchSession());
 
   if (session) {
     // If there is a session, check if it is valid (e.g. "last activity" time

Diff for: packages/replay/test/unit/session/fetchSession.test.ts

@@ -15,18 +15,13 @@ afterEach(() => {
   WINDOW.sessionStorage.clear();
 });
 
-const SAMPLE_RATES = {
-  sessionSampleRate: 1.0,
-  errorSampleRate: 0.0,
-};
-
 it('fetches a valid and sampled session', function () {
   WINDOW.sessionStorage.setItem(
     REPLAY_SESSION_KEY,
     '{"id":"fd09adfc4117477abc8de643e5a5798a","sampled": "session","started":1648827162630,"lastActivity":1648827162658}',
   );
 
-  expect(fetchSession(SAMPLE_RATES)).toEqual({
+  expect(fetchSession()).toEqual({
     id: 'fd09adfc4117477abc8de643e5a5798a',
     lastActivity: 1648827162658,
     segmentId: 0,
@@ -41,7 +36,7 @@ it('fetches an unsampled session', function () {
     '{"id":"fd09adfc4117477abc8de643e5a5798a","sampled": false,"started":1648827162630,"lastActivity":1648827162658}',
   );
 
-  expect(fetchSession(SAMPLE_RATES)).toEqual({
+  expect(fetchSession()).toEqual({
     id: 'fd09adfc4117477abc8de643e5a5798a',
     lastActivity: 1648827162658,
     segmentId: 0,
@@ -50,29 +45,14 @@ it('fetches an unsampled session', function () {
   });
 });
 
-it('auto-fixes a session without sampled', function () {
-  WINDOW.sessionStorage.setItem(
-    REPLAY_SESSION_KEY,
-    '{"id":"fd09adfc4117477abc8de643e5a5798a","started":1648827162630,"lastActivity":1648827162658}',
-  );
-
-  expect(fetchSession(SAMPLE_RATES)).toEqual({
-    id: 'fd09adfc4117477abc8de643e5a5798a',
-    lastActivity: 1648827162658,
-    segmentId: 0,
-    sampled: 'session',
-    started: 1648827162630,
-  });
-});
-
 it('fetches a session that does not exist', function () {
-  expect(fetchSession(SAMPLE_RATES)).toBe(null);
+  expect(fetchSession()).toBe(null);
 });
 
 it('fetches an invalid session', function () {
   WINDOW.sessionStorage.setItem(REPLAY_SESSION_KEY, '{"id":"fd09adfc4117477abc8de643e5a5798a",');
 
-  expect(fetchSession(SAMPLE_RATES)).toBe(null);
+  expect(fetchSession()).toBe(null);
 });
 
 it('safely attempts to fetch session when Session Storage is disabled', function () {
@@ -85,5 +65,5 @@ it('safely attempts to fetch session when Session Storage is disabled', function
     },
   });
 
-  expect(fetchSession(SAMPLE_RATES)).toEqual(null);
+  expect(fetchSession()).toEqual(null);
 });

Diff for: packages/replay/test/unit/session/getSession.test.ts

@@ -58,7 +58,7 @@ it('creates a non-sticky session when one does not exist', function () {
   });
 
   // Should not have anything in storage
-  expect(FetchSession.fetchSession(SAMPLE_RATES)).toBe(null);
+  expect(FetchSession.fetchSession()).toBe(null);
 });
 
 it('creates a non-sticky session, regardless of session existing in sessionStorage', function () {
@@ -98,7 +98,7 @@ it('creates a non-sticky session, when one is expired', function () {
 });
 
 it('creates a sticky session when one does not exist', function () {
-  expect(FetchSession.fetchSession(SAMPLE_RATES)).toBe(null);
+  expect(FetchSession.fetchSession()).toBe(null);
 
   const { session } = getSession({
     expiry: 900000,
@@ -119,7 +119,7 @@ it('creates a sticky session when one does not exist', function () {
   });
 
   // Should not have anything in storage
-  expect(FetchSession.fetchSession(SAMPLE_RATES)).toEqual({
+  expect(FetchSession.fetchSession()).toEqual({
     id: 'test_session_id',
     segmentId: 0,
     lastActivity: expect.any(Number),