reverting parts of the rapid periodic sync, unfortunately it suffers from the same issue as the one shot workers -

the system can ignore them if the application process is in the background

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/Session.kt

@@ -120,10 +120,11 @@ interface Session :
     fun requireBackgroundSync()
 
     /**
-     * Launches infinite periodic background syncs
-     * Doze mode will probably interrupt rapid sync, but it should start up again the next time we run a periodic sync
+     * Launches infinite self rescheduling background syncs
+     * This does not work in doze mode :/
+     * If battery optimization is on it can work in app standby but that's all :/
      */
-    fun startAutomaticBackgroundSync(timeOutInSeconds: Long, rapidSync: Boolean, repeatDelayInSeconds: Long)
+    fun startAutomaticBackgroundSync(timeOutInSeconds: Long, repeatDelayInSeconds: Long)
 
     fun stopAnyBackgroundSync()
 

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/di/WorkManagerProvider.kt

@@ -50,16 +50,6 @@ internal class WorkManagerProvider @Inject constructor(
             PeriodicWorkRequestBuilder<W>(repeatInterval, repeatIntervalTimeUnit)
                     .addTag(tag)
 
-    /**
-     * Create a PeriodicWorkRequestBuilder, with the Matrix SDK tag
-     */
-    inline fun <reified W : ListenableWorker> matrixPeriodicWorkRequestBuilder(repeatInterval: Long,
-                                                                               repeatIntervalTimeUnit: TimeUnit,
-                                                                               flexTimeInterval: Long,
-                                                                               flexTimeIntervalUnit: TimeUnit) =
-            PeriodicWorkRequestBuilder<W>(repeatInterval, repeatIntervalTimeUnit, flexTimeInterval, flexTimeIntervalUnit)
-                    .addTag(tag)
-
     /**
      * Cancel all works instantiated by the Matrix SDK for the current session, and not those from the SDK client, or for other sessions
      */

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/DefaultSession.kt

@@ -184,8 +184,8 @@ internal class DefaultSession @Inject constructor(
         SyncWorker.requireBackgroundSync(workManagerProvider, sessionId)
     }
 
-    override fun startAutomaticBackgroundSync(timeOutInSeconds: Long, rapidSync: Boolean, repeatDelayInSeconds: Long) {
-        SyncWorker.automaticallyPeriodicBackgroundSync(workManagerProvider, sessionId, timeOutInSeconds, rapidSync, repeatDelayInSeconds)
+    override fun startAutomaticBackgroundSync(timeOutInSeconds: Long, repeatDelayInSeconds: Long) {
+        SyncWorker.automaticallyBackgroundSync(workManagerProvider, sessionId, timeOutInSeconds, repeatDelayInSeconds)
     }
 
     override fun stopAnyBackgroundSync() {

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/sync/job/SyncWorker.kt

@@ -17,9 +17,7 @@ package org.matrix.android.sdk.internal.session.sync.job
 
 import android.content.Context
 import androidx.work.BackoffPolicy
-import androidx.work.ExistingPeriodicWorkPolicy
 import androidx.work.ExistingWorkPolicy
-import androidx.work.WorkRequest
 import androidx.work.WorkerParameters
 import com.squareup.moshi.JsonClass
 import org.matrix.android.sdk.api.failure.isTokenError
@@ -75,7 +73,7 @@ internal class SyncWorker(context: Context,
                     Result.success().also {
                         if (params.periodic) {
                             // we want to schedule another one after delay
-                            automaticallyRapidBackgroundSync(workManagerProvider, params.sessionId, params.timeout, params.delay)
+                            automaticallyBackgroundSync(workManagerProvider, params.sessionId, params.timeout, params.delay)
                         }
                     }
                 },
@@ -103,8 +101,6 @@ internal class SyncWorker(context: Context,
 
     companion object {
         private const val BG_SYNC_WORK_NAME = "BG_SYNCP"
-        private const val BG_RAPID_SYNC_WORK_NAME = "BG_RAPID_SYNCP"
-        private const val BG_PERIODIC_SYNC_WORK_NAME = "BG_PERIODIC_SYNCP"
 
         fun requireBackgroundSync(workManagerProvider: WorkManagerProvider, sessionId: String, serverTimeout: Long = 0) {
             val data = WorkerParamsFactory.toData(Params(sessionId, serverTimeout, 0L, false))
@@ -113,12 +109,11 @@ internal class SyncWorker(context: Context,
                     .setBackoffCriteria(BackoffPolicy.LINEAR, WorkManagerProvider.BACKOFF_DELAY_MILLIS, TimeUnit.MILLISECONDS)
                     .setInputData(data)
                     .build()
-            // If we've already scheduled a sync that's not yet run, defer to the existing one
             workManagerProvider.workManager
-                    .enqueueUniqueWork(BG_SYNC_WORK_NAME, ExistingWorkPolicy.KEEP, workRequest)
+                    .enqueueUniqueWork(BG_SYNC_WORK_NAME, ExistingWorkPolicy.APPEND_OR_REPLACE, workRequest)
         }
 
-        fun automaticallyRapidBackgroundSync(workManagerProvider: WorkManagerProvider, sessionId: String, serverTimeout: Long = 0, delayInSeconds: Long = 30) {
+        fun automaticallyBackgroundSync(workManagerProvider: WorkManagerProvider, sessionId: String, serverTimeout: Long = 0, delayInSeconds: Long = 30) {
             val data = WorkerParamsFactory.toData(Params(sessionId, serverTimeout, delayInSeconds, true))
             val workRequest = workManagerProvider.matrixOneTimeWorkRequestBuilder<SyncWorker>()
                     .setConstraints(WorkManagerProvider.workConstraints)
@@ -128,28 +123,12 @@ internal class SyncWorker(context: Context,
                     .build()
             // Avoid risking multiple chains of syncs by replacing the existing chain
             workManagerProvider.workManager
-                    .enqueueUniqueWork(BG_RAPID_SYNC_WORK_NAME, ExistingWorkPolicy.REPLACE, workRequest)
-        }
-
-        fun automaticallyPeriodicBackgroundSync(workManagerProvider: WorkManagerProvider, sessionId: String, serverTimeout: Long = 0, restartRapidSync: Boolean = true, delayInSeconds: Long = 30) {
-            val data = WorkerParamsFactory.toData(Params(sessionId, serverTimeout, delayInSeconds, restartRapidSync))
-            val workRequest = workManagerProvider.matrixPeriodicWorkRequestBuilder<SyncWorker>(1, TimeUnit.HOURS, 15, TimeUnit.MINUTES)
-                    .setConstraints(WorkManagerProvider.workConstraints)
-                    .setInputData(data)
-                    .setBackoffCriteria(BackoffPolicy.LINEAR, WorkRequest.MIN_BACKOFF_MILLIS, TimeUnit.MILLISECONDS)
-                    .build()
-
-            workManagerProvider.workManager
-                    .enqueueUniquePeriodicWork(BG_PERIODIC_SYNC_WORK_NAME, ExistingPeriodicWorkPolicy.KEEP, workRequest)
+                    .enqueueUniqueWork(BG_SYNC_WORK_NAME, ExistingWorkPolicy.REPLACE, workRequest)
         }
 
         fun stopAnyBackgroundSync(workManagerProvider: WorkManagerProvider) {
             workManagerProvider.workManager
                     .cancelUniqueWork(BG_SYNC_WORK_NAME)
-            workManagerProvider.workManager
-                    .cancelUniqueWork(BG_RAPID_SYNC_WORK_NAME)
-            workManagerProvider.workManager
-                    .cancelUniqueWork(BG_PERIODIC_SYNC_WORK_NAME)
         }
     }
 }

vector/src/fdroid/java/im/vector/app/fdroid/BackgroundSyncStarter.kt

@@ -19,13 +19,9 @@ package im.vector.app.fdroid
 import android.content.Context
 import im.vector.app.core.di.ActiveSessionHolder
 import im.vector.app.fdroid.receiver.AlarmSyncBroadcastReceiver
-import im.vector.app.fdroid.service.GuardService
 import im.vector.app.features.settings.BackgroundSyncMode
 import im.vector.app.features.settings.VectorPreferences
 import timber.log.Timber
-import android.content.Intent
-import androidx.core.content.ContextCompat
-import org.matrix.android.sdk.internal.session.sync.job.SyncService
 
 object BackgroundSyncStarter {
     fun start(context: Context, vectorPreferences: VectorPreferences, activeSessionHolder: ActiveSessionHolder) {
@@ -37,7 +33,6 @@ object BackgroundSyncStarter {
                     Timber.i("## Sync: Work scheduled to periodically sync in ${vectorPreferences.backgroundSyncDelay()}s")
                     activeSession.startAutomaticBackgroundSync(
                             vectorPreferences.backgroundSyncTimeOut().toLong(),
-                            true,
                             vectorPreferences.backgroundSyncDelay().toLong()
                     )
                 }

vector/src/gplay/java/im/vector/app/push/fcm/FcmHelper.kt

@@ -111,7 +111,6 @@ object FcmHelper {
         val activeSession = activeSessionHolder.getSafeActiveSession() ?: return
         activeSession.startAutomaticBackgroundSync(
                 vectorPreferences.backgroundSyncTimeOut().toLong(),
-                false,
                 vectorPreferences.backgroundSyncDelay().toLong()
         )
     }

vector/src/main/java/im/vector/app/features/call/webrtc/WebRtcCallManager.kt

@@ -373,7 +373,7 @@ class WebRtcCallManager @Inject constructor(
         if (isInBackground) {
             if (FcmHelper.isPushSupported()) {
                 // only for push version as fdroid version is already doing it?
-                currentSession?.startAutomaticBackgroundSync(30, true, 0)
+                currentSession?.startAutomaticBackgroundSync(30, 0)
             } else {
                 // Maybe increase sync freq? but how to set back to default values?
             }