feat: add background notification retry logic with configurable stayalive duration [WPB-22041] (#4391)

Author: MohamadJaara

app/src/main/kotlin/com/wire/android/notification/WireNotificationManager.kt

@@ -19,6 +19,7 @@
 package com.wire.android.notification
 
 import androidx.annotation.VisibleForTesting
+import com.wire.android.BuildConfig
 import com.wire.android.R
 import com.wire.android.appLogger
 import com.wire.android.di.KaliumCoreLogic
@@ -47,6 +48,7 @@ import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.SupervisorJob
 import kotlinx.coroutines.cancel
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.cancellable
@@ -62,10 +64,12 @@ import kotlinx.coroutines.flow.stateIn
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
+import java.net.UnknownHostException
 import java.util.concurrent.ConcurrentHashMap
 import java.util.concurrent.atomic.AtomicReference
 import javax.inject.Inject
 import javax.inject.Singleton
+import kotlin.time.Duration
 import kotlin.time.Duration.Companion.seconds
 
 @OptIn(ExperimentalCoroutinesApi::class)
@@ -165,13 +169,70 @@ class WireNotificationManager @Inject constructor(
         val observeMessagesJob = observeMessageNotificationsOnceJob(userId)
         val observeCallsJob = observeCallNotificationsOnceJob(userId)
 
-        appLogger.d("$TAG start syncing")
-        syncLifecycleManager.syncTemporarily(userId, STAY_ALIVE_TIME_ON_PUSH_DURATION)
+        val stayAliveDuration = BuildConfig.BACKGROUND_NOTIFICATION_STAY_ALIVE_SECONDS.seconds
+
+        if (BuildConfig.BACKGROUND_NOTIFICATION_RETRY_ENABLED) {
+            appLogger.d("$TAG start syncing with retry logic and extended duration (${stayAliveDuration.inWholeSeconds}s)")
+            retrySync(userId, stayAliveDuration)
+        } else {
+            appLogger.d("$TAG start syncing without retry logic, default duration (${stayAliveDuration.inWholeSeconds}s)")
+            syncLifecycleManager.syncTemporarily(userId, stayAliveDuration)
+        }
 
         observeMessagesJob?.cancel("$TAG checked the notifications once, canceling observing.")
         observeCallsJob?.cancel("$TAG checked the calls once, canceling observing.")
     }
 
+    /**
+     * Retries sync operation with exponential backoff for transient network failures.
+     * This is critical for background notifications during Doze mode where network
+     * may not be immediately available despite WorkManager constraints.
+     */
+    @Suppress("TooGenericExceptionCaught")
+    private suspend fun retrySync(userId: UserId, stayAliveDuration: Duration) {
+        val maxRetries = MAX_SYNC_RETRY
+        var attempt = 0
+        var lastException: Exception? = null
+
+        while (attempt < maxRetries) {
+            try {
+                appLogger.d("$TAG Sync attempt ${attempt + 1}/$maxRetries")
+                syncLifecycleManager.syncTemporarily(userId, stayAliveDuration)
+                appLogger.i("$TAG Sync succeeded on attempt ${attempt + 1}")
+                return // Success, exit retry loop
+            } catch (e: Exception) {
+                lastException = e
+
+                // Only retry on network-related errors
+                val isRetryable = when (e) {
+                    is UnknownHostException -> true
+                    else -> e.cause is UnknownHostException
+                }
+
+                if (!isRetryable) {
+                    appLogger.w("$TAG Non-retryable error during sync: ${e.message}")
+                    throw e
+                }
+
+                attempt++
+                if (attempt < maxRetries) {
+                    // Exponential backoff: 1s, 2s, 4s
+                    val delaySeconds = (1L shl (attempt - 1))
+                    appLogger.w("$TAG Network error on attempt $attempt, retrying in ${delaySeconds}s: ${e.message}")
+                    delay(delaySeconds.seconds)
+                } else {
+                    appLogger.e("$TAG All $maxRetries sync attempts failed with network errors")
+                }
+            }
+        }
+
+        // If we exhausted all retries, log and rethrow
+        lastException?.let {
+            appLogger.e("$TAG Sync failed after $maxRetries attempts: ${it.message}")
+            throw it
+        }
+    }
+
     private suspend fun observeMessageNotificationsOnceJob(userId: UserId): Job? {
         val isMessagesAlreadyObserving =
             observingWhileRunningJobs.userJobs[userId]?.run { messagesJob.isActive }
@@ -527,6 +588,6 @@ class WireNotificationManager @Inject constructor(
 
     companion object {
         private const val TAG = "WireNotificationManager"
-        private val STAY_ALIVE_TIME_ON_PUSH_DURATION = 1.seconds
+        private const val MAX_SYNC_RETRY = 3
     }
 }

app/src/nonfree/kotlin/com/wire/android/services/WireFirebaseMessagingService.kt

@@ -18,7 +18,9 @@
 
 package com.wire.android.services
 
+import androidx.work.Constraints
 import androidx.work.ExistingWorkPolicy
+import androidx.work.NetworkType
 import androidx.work.OneTimeWorkRequestBuilder
 import androidx.work.OutOfQuotaPolicy
 import androidx.work.WorkManager
@@ -78,11 +80,22 @@ class WireFirebaseMessagingService : FirebaseMessagingService() {
     }
 
     private fun enqueueNotificationFetchWorker(userId: String) {
-        val request = OneTimeWorkRequestBuilder<NotificationFetchWorker>()
+        val requestBuilder = OneTimeWorkRequestBuilder<NotificationFetchWorker>()
             .setExpedited(OutOfQuotaPolicy.RUN_AS_NON_EXPEDITED_WORK_REQUEST)
             .setInputData(workDataOf(NotificationFetchWorker.USER_ID_INPUT_DATA to userId))
-            .build()
 
+        // Only add network constraints if background notification retry feature is enabled
+        if (BuildConfig.BACKGROUND_NOTIFICATION_RETRY_ENABLED) {
+            val constraints = Constraints.Builder()
+                .setRequiredNetworkType(NetworkType.CONNECTED)
+                .build()
+            requestBuilder.setConstraints(constraints)
+            appLogger.d("$TAG: Enqueued NotificationFetchWorker with network constraints")
+        } else {
+            appLogger.d("$TAG: Enqueued NotificationFetchWorker without network constraints")
+        }
+
+        val request = requestBuilder.build()
         val workManager = WorkManager.getInstance(applicationContext)
 
         workManager.enqueueUniqueWork(

buildSrc/src/main/kotlin/customization/FeatureConfigs.kt

@@ -125,4 +125,16 @@ enum class FeatureConfigs(val value: String, val configType: ConfigType) {
     MEETINGS_ENABLED("meetings_enabled", ConfigType.BOOLEAN),
 
     USE_ASYNC_FLUSH_LOGGING("use_async_flush_logging", ConfigType.BOOLEAN),
+
+    /**
+     * Background notification retry logic
+     * Enables retry with exponential backoff for background notification sync failures
+     */
+    BACKGROUND_NOTIFICATION_RETRY_ENABLED("background_notification_retry_enabled", ConfigType.BOOLEAN),
+
+    /**
+     * Extended stay-alive duration (in seconds) when background notification retry is enabled
+     * Controls how long the sync connection stays alive after receiving a push notification
+     */
+    BACKGROUND_NOTIFICATION_STAY_ALIVE_SECONDS("background_notification_stay_alive_seconds", ConfigType.INT),
 }

default.json

@@ -81,7 +81,10 @@
             "analytics_app_key": "8ffae535f1836ed5f58fd5c8a11c00eca07c5438",
             "analytics_server_url": "https://wire.count.ly/",
             "enable_new_registration": true,
-            "use_async_flush_logging" : true
+            "use_strict_mls_filter": false,
+            "use_async_flush_logging" : true,
+            "background_notification_retry_enabled": true,
+            "background_notification_stay_alive_seconds": 5
         },
         "fdroid": {
             "application_id": "com.wire",
@@ -152,5 +155,7 @@
     "is_mls_reset_enabled": true,
     "use_strict_mls_filter": false,
     "meetings_enabled": false,
-    "emm_support_enabled": true
+    "emm_support_enabled": true,
+    "background_notification_retry_enabled": false,
+    "background_notification_stay_alive_seconds": 1
 }