fallback mode

Author: themiswang

firebase-sessions/src/main/kotlin/com/google/firebase/sessions/SharedSessionRepository.kt

@@ -49,23 +49,34 @@ constructor(
 ) : SharedSessionRepository {
   /** Local copy of the session data. Can get out of sync, must be double-checked in datastore. */
   private lateinit var localSessionData: SessionData
+  private var shouldFallback: Boolean = false
 
   init {
-    CoroutineScope(backgroundDispatcher).launch {
-      sessionDataStore.data.collect { sessionData ->
-        localSessionData = sessionData
-        val sessionId = sessionData.sessionDetails.sessionId
+    if (!sessionsSettings.sessionsEnabled) {
+      shouldFallback = true
+    } else {
+      CoroutineScope(backgroundDispatcher).launch {
+        sessionDataStore.data.collect { sessionData ->
+          localSessionData = sessionData
+          val sessionId = sessionData.sessionDetails.sessionId
 
-        FirebaseSessionsDependencies.getRegisteredSubscribers().values.forEach { subscriber ->
-          // Notify subscribers, regardless of sampling and data collection state
-          subscriber.onSessionChanged(SessionSubscriber.SessionDetails(sessionId))
-          Log.d(TAG, "Notified ${subscriber.sessionSubscriberName} of new session $sessionId")
+          FirebaseSessionsDependencies.getRegisteredSubscribers().values.forEach { subscriber ->
+            // Notify subscribers, regardless of sampling and data collection state
+            subscriber.onSessionChanged(SessionSubscriber.SessionDetails(sessionId))
+            Log.d(TAG, "Notified ${subscriber.sessionSubscriberName} of new session $sessionId")
+          }
         }
       }
     }
   }
 
   override fun appBackground() {
+    // Fallback mode, not using datastore, pre multi-process support stage
+    if (shouldFallback) {
+      localSessionData.copy(backgroundTime = timeProvider.currentTime())
+      return
+    }
+
     if (!::localSessionData.isInitialized) {
       Log.d(TAG, "App backgrounded, but local SessionData not initialized")
       return
@@ -82,6 +93,27 @@ constructor(
   }
 
   override fun appForeground() {
+    // Fallback mode, not using datastore, pre multi-process support stage
+    if (shouldFallback) {
+      if (shouldInitiateNewSession(localSessionData)) {
+        val newSessionDetails = sessionGenerator.generateNewSession(localSessionData.sessionDetails)
+        localSessionData.copy(sessionDetails = newSessionDetails)
+        CoroutineScope(backgroundDispatcher).launch {
+          // Only notify subscriber for session change, not send to event to firelog
+          FirebaseSessionsDependencies.getRegisteredSubscribers().values.forEach { subscriber ->
+            subscriber.onSessionChanged(
+              SessionSubscriber.SessionDetails(newSessionDetails.sessionId)
+            )
+            Log.d(
+              TAG,
+              "Notified ${subscriber.sessionSubscriberName} of new session $newSessionDetails.sessionId with fallback mode"
+            )
+          }
+        }
+      }
+      return
+    }
+
     if (!::localSessionData.isInitialized) {
       Log.d(TAG, "App foregrounded, but local SessionData not initialized")
       return