feat: use battery saving sync intervals

Author: ovitrif

app/src/main/java/to/bitkit/androidServices/LightningNodeService.kt

@@ -9,6 +9,9 @@ import android.os.IBinder
 import androidx.annotation.RequiresApi
 import androidx.core.app.NotificationCompat
 import androidx.core.content.ContextCompat
+import androidx.lifecycle.DefaultLifecycleObserver
+import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.ProcessLifecycleOwner
 import dagger.hilt.android.AndroidEntryPoint
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.CoroutineScope
@@ -54,10 +57,15 @@ class LightningNodeService : Service() {
     @Inject
     lateinit var cacheStore: CacheStore
 
+    private var lifecycleObserver: AppLifecycleObserver? = null
+
     override fun onCreate() {
         super.onCreate()
         startForeground(ID_NOTIFICATION_NODE, createNotification())
         setupService()
+        lifecycleObserver = AppLifecycleObserver().also {
+            ProcessLifecycleOwner.get().lifecycle.addObserver(it)
+        }
     }
 
     private fun setupService() {
@@ -145,6 +153,7 @@ class LightningNodeService : Service() {
 
     override fun onDestroy() {
         Logger.debug("onDestroy", context = TAG)
+        lifecycleObserver?.let { ProcessLifecycleOwner.get().lifecycle.removeObserver(it) }
         serviceScope.launch {
             lightningRepo.stop()
             serviceScope.cancel()
@@ -164,6 +173,24 @@ class LightningNodeService : Service() {
 
     override fun onBind(intent: Intent?): IBinder? = null
 
+    private inner class AppLifecycleObserver : DefaultLifecycleObserver {
+        override fun onStart(owner: LifecycleOwner) {
+            serviceScope.launch {
+                lightningRepo.disableBatterySavingMode()
+                    .onSuccess { Logger.debug("Sync intervals exited battery saving mode", context = TAG) }
+                    .onFailure { Logger.warn("Error setting sync intervals out of battery saving", it, context = TAG) }
+            }
+        }
+
+        override fun onStop(owner: LifecycleOwner) {
+            serviceScope.launch {
+                lightningRepo.enableBatterySavingMode()
+                    .onSuccess { Logger.debug("Sync intervals entered battery saving mode", context = TAG) }
+                    .onFailure { Logger.warn("Error setting sync intervals set to battery saving", it, context = TAG) }
+            }
+        }
+    }
+
     companion object {
         const val CHANNEL_ID_NODE = "bitkit_notification_channel_node"
         const val TAG = "LightningNodeService"

app/src/main/java/to/bitkit/env/Env.kt

@@ -4,6 +4,7 @@ import android.os.Build
 import org.lightningdevkit.ldknode.LogLevel
 import org.lightningdevkit.ldknode.Network
 import org.lightningdevkit.ldknode.PeerDetails
+import org.lightningdevkit.ldknode.RuntimeSyncIntervals
 import to.bitkit.BuildConfig
 import to.bitkit.ext.ensureDir
 import to.bitkit.ext.of
@@ -20,12 +21,17 @@ internal object Env {
     val e2eBackend = BuildConfig.E2E_BACKEND.lowercase()
     val network = Network.valueOf(BuildConfig.NETWORK)
     val locales = BuildConfig.LOCALES.split(",")
-    const val walletSyncIntervalSecs = 10_uL
     val platform = "Android ${Build.VERSION.RELEASE} (API ${Build.VERSION.SDK_INT})"
     const val version = "${BuildConfig.VERSION_NAME} (${BuildConfig.VERSION_CODE})"
 
     val ldkLogLevel = LogLevel.TRACE
 
+    val syncIntervals = RuntimeSyncIntervals(
+        onchainWalletSyncIntervalSecs = 80_uL, // ldk-node default
+        lightningWalletSyncIntervalSecs = 30_uL, // ldk-node default
+        feeRateCacheUpdateIntervalSecs = 600_uL, // ldk-node default (10 min)
+    )
+
     val trustedLnPeers
         get() = when (network) {
             Network.BITCOIN -> listOf(Peers.lnd1, Peers.lnd3, Peers.lnd4)

app/src/main/java/to/bitkit/repositories/LightningRepo.kt

@@ -36,6 +36,7 @@ import org.lightningdevkit.ldknode.ChannelDataMigration
 import org.lightningdevkit.ldknode.ChannelDetails
 import org.lightningdevkit.ldknode.ClosureReason
 import org.lightningdevkit.ldknode.Event
+import org.lightningdevkit.ldknode.NodeException
 import org.lightningdevkit.ldknode.NodeStatus
 import org.lightningdevkit.ldknode.PaymentDetails
 import org.lightningdevkit.ldknode.PaymentId
@@ -439,6 +440,30 @@ class LightningRepo @Inject constructor(
     /** Clear pending sync flag. Called when manual pull-to-refresh takes priority. */
     fun clearPendingSync() = syncPending.set(false)
 
+    suspend fun enableBatterySavingMode(): Result<Unit> = executeWhenNodeRunning("enableBatterySavingMode") {
+        runCatching {
+            lightningService.updateSyncIntervals(lightningService.batterySavingIntervals())
+        }.recoverCatching { e ->
+            if (e is NodeException.BackgroundSyncNotEnabled) {
+                Logger.warn("Background sync not enabled, skipping sync intervals update", context = TAG)
+            } else {
+                throw e
+            }
+        }
+    }
+
+    suspend fun disableBatterySavingMode(): Result<Unit> = executeWhenNodeRunning("disableBatterySavingMode") {
+        runCatching {
+            lightningService.updateSyncIntervals(lightningService.defaultSyncIntervals())
+        }.recoverCatching { e ->
+            if (e is NodeException.BackgroundSyncNotEnabled) {
+                Logger.warn("Background sync not enabled, skipping sync intervals update", context = TAG)
+            } else {
+                throw e
+            }
+        }
+    }
+
     private suspend fun refreshChannelCache() = withContext(bgDispatcher) {
         lightningService.channels?.forEach {
             channelCache[it.channelId] = it

app/src/main/java/to/bitkit/services/LightningService.kt

@@ -34,6 +34,7 @@ import org.lightningdevkit.ldknode.NodeStatus
 import org.lightningdevkit.ldknode.PaymentDetails
 import org.lightningdevkit.ldknode.PaymentId
 import org.lightningdevkit.ldknode.PeerDetails
+import org.lightningdevkit.ldknode.RuntimeSyncIntervals
 import org.lightningdevkit.ldknode.SpendableUtxo
 import org.lightningdevkit.ldknode.Txid
 import org.lightningdevkit.ldknode.defaultConfig
@@ -193,9 +194,9 @@ class LightningService @Inject constructor(
             serverUrl = serverUrl,
             config = ElectrumSyncConfig(
                 BackgroundSyncConfig(
-                    onchainWalletSyncIntervalSecs = Env.walletSyncIntervalSecs,
-                    lightningWalletSyncIntervalSecs = Env.walletSyncIntervalSecs,
-                    feeRateCacheUpdateIntervalSecs = Env.walletSyncIntervalSecs,
+                    onchainWalletSyncIntervalSecs = Env.syncIntervals.onchainWalletSyncIntervalSecs,
+                    lightningWalletSyncIntervalSecs = Env.syncIntervals.lightningWalletSyncIntervalSecs,
+                    feeRateCacheUpdateIntervalSecs = Env.syncIntervals.feeRateCacheUpdateIntervalSecs,
                 ),
             ),
         )
@@ -275,6 +276,19 @@ class LightningService @Inject constructor(
         Logger.debug("LDK synced", context = TAG)
     }
 
+    suspend fun updateSyncIntervals(intervals: RuntimeSyncIntervals) = withContext(bgDispatcher) {
+        val node = this@LightningService.node ?: throw ServiceError.NodeNotSetup()
+        ServiceQueue.LDK.background {
+            node.updateSyncIntervals(intervals)
+        }
+        Logger.info("Sync intervals updated", context = TAG)
+    }
+
+    fun defaultSyncIntervals(): RuntimeSyncIntervals = Env.syncIntervals
+
+    fun batterySavingIntervals(): RuntimeSyncIntervals =
+        org.lightningdevkit.ldknode.batterySavingSyncIntervals()
+
     suspend fun sign(message: String): String {
         val node = this.node ?: throw ServiceError.NodeNotSetup()
         val msg = runCatching { message.uByteList }.getOrNull() ?: throw ServiceError.InvalidNodeSigningMessage()