feat: Tidy initialisation with better warnings

playground/session-recordings/index.html

@@ -100,6 +100,23 @@
                 capture_performance: true,
             })
 
+            posthog.init(
+                'phc_other',
+                {
+                    api_host: 'http://localhost:8000',
+                    disable_session_recording: true,
+                    capture_performance: true,
+                },
+                'other'
+            )
+
+            posthog.capture('event')
+            posthog.capture('event2')
+            posthog.people.set({ test: true })
+            posthog.other.capture('other_event')
+            posthog.other.people.set({ test: true })
+            console.log(posthog)
+
             setTimeout(() => {
                 posthog.debug()
                 document.getElementById('current-session-id').innerHTML = posthog.sessionRecording.sessionId

src/__tests__/posthog-core.identify.js

@@ -7,7 +7,11 @@ jest.mock('../gdpr-utils', () => ({
 }))
 jest.mock('../decide')
 
-given('lib', () => Object.assign(new PostHog(), given.overrides))
+given('lib', () => {
+    const posthog = new PostHog()
+    posthog.init('testtoken', given.config)
+    return Object.assign(posthog, given.overrides)
+})
 
 describe('identify()', () => {
     given(
@@ -339,10 +343,6 @@ describe('reset()', () => {
         persistence: new PostHogPersistence(given.config),
     }))
 
-    beforeEach(() => {
-        given.lib._init('testtoken', given.config, 'testhog')
-    })
-
     it('clears persistence', () => {
         given.lib.persistence.register({ $enabled_feature_flags: { flag: 'variant', other: true } })
         expect(given.lib.persistence.props['$enabled_feature_flags']).toEqual({ flag: 'variant', other: true })

src/__tests__/posthog-core.js

@@ -16,7 +16,11 @@ jest.mock('../utils', () => ({
     document: { title: 'test' },
 }))
 
-given('lib', () => Object.assign(new PostHog(), given.overrides))
+given('lib', () => {
+    const posthog = new PostHog()
+    posthog._init('testtoken', given.config, 'testhog')
+    return Object.assign(posthog, given.overrides)
+})
 
 describe('capture()', () => {
     given('eventName', () => '$event')
@@ -29,6 +33,7 @@ describe('capture()', () => {
     given('config', () => ({
         property_blacklist: [],
         _onCapture: jest.fn(),
+        get_device_id: jest.fn().mockReturnValue('device-id'),
     }))
 
     given('overrides', () => ({
@@ -38,11 +43,13 @@ describe('capture()', () => {
         persistence: {
             remove_event_timer: jest.fn(),
             properties: jest.fn(),
+            update_config: jest.fn(),
         },
         sessionPersistence: {
             update_search_keyword: jest.fn(),
             update_campaign_params: jest.fn(),
             update_referrer_info: jest.fn(),
+            update_config: jest.fn(),
             properties: jest.fn(),
         },
         compression: {},

src/extensions/sessionrecording.ts

@@ -101,6 +101,15 @@ export class SessionRecording {
         })
     }
 
+    private getSessionManager() {
+        if (!this.instance.sessionManager) {
+            logger.error('Session recording started without valid sessionManager')
+            return
+        }
+
+        return this.instance.sessionManager
+    }
+
     startRecordingIfEnabled() {
         if (this.isRecordingEnabled()) {
             this.startCaptureAndTrySendingQueuedSnapshots()
@@ -185,14 +194,18 @@ export class SessionRecording {
     }
 
     private _startCapture() {
-        // According to the rrweb docs, rrweb is not supported on IE11 and below:
-        // "rrweb does not support IE11 and below because it uses the MutationObserver API which was supported by these browsers."
-        // https://github.com/rrweb-io/rrweb/blob/master/guide.md#compatibility-note
-        //
-        // However, MutationObserver does exist on IE11, it just doesn't work well and does not detect all changes.
-        // Instead, when we load "recorder.js", the first JS error is about "Object.assign" being undefined.
-        // Thus instead of MutationObserver, we look for this function and block recording if it's undefined.
+        const sessionManager = this.getSessionManager()
+        if (!sessionManager) {
+            return
+        }
         if (typeof Object.assign === 'undefined') {
+            // According to the rrweb docs, rrweb is not supported on IE11 and below:
+            // "rrweb does not support IE11 and below because it uses the MutationObserver API which was supported by these browsers."
+            // https://github.com/rrweb-io/rrweb/blob/master/guide.md#compatibility-note
+            //
+            // However, MutationObserver does exist on IE11, it just doesn't work well and does not detect all changes.
+            // Instead, when we load "recorder.js", the first JS error is about "Object.assign" being undefined.
+            // Thus instead of MutationObserver, we look for this function and block recording if it's undefined.
             return
         }
 
@@ -203,7 +216,7 @@ export class SessionRecording {
 
         this.captureStarted = true
         // We want to ensure the sessionManager is reset if necessary on load of the recorder
-        this.instance.sessionManager.checkAndGetSessionAndWindowId()
+        sessionManager.checkAndGetSessionAndWindowId()
 
         const recorderJS = this.getRecordingVersion() === 'v2' ? 'recorder-v2.js' : 'recorder.js'
 
@@ -231,6 +244,10 @@ export class SessionRecording {
     }
 
     private _updateWindowAndSessionIds(event: eventWithTime) {
+        const sessionManager = this.getSessionManager()
+        if (!sessionManager) {
+            return
+        }
         // Some recording events are triggered by non-user events (e.g. "X minutes ago" text updating on the screen).
         // We don't want to extend the session or trigger a new session in these cases. These events are designated by event
         // type -> incremental update, and source -> mutation.
@@ -258,7 +275,7 @@ export class SessionRecording {
         }
 
         // We only want to extend the session if it is an interactive event.
-        const { windowId, sessionId } = this.instance.sessionManager.checkAndGetSessionAndWindowId(
+        const { windowId, sessionId } = sessionManager.checkAndGetSessionAndWindowId(
             !isUserInteraction,
             event.timestamp
         )