fix: android background backups (#21795)

* upload using dart client

* add connectivity api

* respect backup network setting

* comment as to why we need to wait for setForegroundAsync call

* log assets skipped due to network constraint

* dynamic spawning -> false

---------

Co-authored-by: shenlong-tanwen <139912620+shalong-tanwen@users.noreply.github.com>
Co-authored-by: Alex <alex.tran1502@gmail.com>

mobile/android/app/src/main/kotlin/app/alextran/immich/MainActivity.kt

@@ -5,6 +5,8 @@ import android.os.Build
 import android.os.ext.SdkExtensions
 import app.alextran.immich.background.BackgroundWorkerApiImpl
 import app.alextran.immich.background.BackgroundWorkerFgHostApi
+import app.alextran.immich.connectivity.ConnectivityApi
+import app.alextran.immich.connectivity.ConnectivityApiImpl
 import app.alextran.immich.images.ThumbnailApi
 import app.alextran.immich.images.ThumbnailsImpl
 import app.alextran.immich.sync.NativeSyncApi
@@ -34,6 +36,7 @@ class MainActivity : FlutterFragmentActivity() {
       NativeSyncApi.setUp(messenger, nativeSyncApiImpl)
       ThumbnailApi.setUp(messenger, ThumbnailsImpl(ctx))
       BackgroundWorkerFgHostApi.setUp(messenger, BackgroundWorkerApiImpl(ctx))
+      ConnectivityApi.setUp(messenger, ConnectivityApiImpl(ctx))
     }
   }
 }

mobile/android/app/src/main/kotlin/app/alextran/immich/background/BackgroundWorker.g.kt

@@ -111,6 +111,7 @@ interface BackgroundWorkerFgHostApi {
 /** Generated interface from Pigeon that represents a handler of messages from Flutter. */
 interface BackgroundWorkerBgHostApi {
   fun onInitialized()
+  fun showNotification(title: String, content: String)
   fun close()
 
   companion object {
@@ -138,6 +139,25 @@ interface BackgroundWorkerBgHostApi {
           channel.setMessageHandler(null)
         }
       }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.immich_mobile.BackgroundWorkerBgHostApi.showNotification$separatedMessageChannelSuffix", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val titleArg = args[0] as String
+            val contentArg = args[1] as String
+            val wrapped: List<Any?> = try {
+              api.showNotification(titleArg, contentArg)
+              listOf(null)
+            } catch (exception: Throwable) {
+              BackgroundWorkerPigeonUtils.wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
       run {
         val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.immich_mobile.BackgroundWorkerBgHostApi.close$separatedMessageChannelSuffix", codec)
         if (api != null) {

mobile/android/app/src/main/kotlin/app/alextran/immich/background/BackgroundWorker.kt

@@ -1,18 +1,27 @@
 package app.alextran.immich.background
 
+import android.app.NotificationChannel
+import android.app.NotificationManager
 import android.content.Context
+import android.content.pm.ServiceInfo.FOREGROUND_SERVICE_TYPE_DATA_SYNC
+import android.os.Build
 import android.os.Handler
 import android.os.Looper
+import android.os.PowerManager
 import android.util.Log
+import androidx.core.app.NotificationCompat
+import androidx.work.ForegroundInfo
 import androidx.work.ListenableWorker
 import androidx.work.WorkerParameters
 import app.alextran.immich.MainActivity
+import app.alextran.immich.R
 import com.google.common.util.concurrent.ListenableFuture
 import com.google.common.util.concurrent.SettableFuture
 import io.flutter.FlutterInjector
 import io.flutter.embedding.engine.FlutterEngine
 import io.flutter.embedding.engine.dart.DartExecutor
 import io.flutter.embedding.engine.loader.FlutterLoader
+import java.util.concurrent.TimeUnit
 
 private const val TAG = "BackgroundWorker"
 
@@ -40,15 +49,32 @@ class BackgroundWorker(context: Context, params: WorkerParameters) :
   /// Flag to track whether the background task has completed to prevent duplicate completions
   private var isComplete = false
 
+  private val notificationManager =
+    ctx.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
+
+  private var foregroundFuture: ListenableFuture<Void>? = null
+
   init {
     if (!loader.initialized()) {
       loader.startInitialization(ctx)
     }
   }
 
+  companion object {
+    private const val NOTIFICATION_CHANNEL_ID = "immich::background_worker::notif"
+    private const val NOTIFICATION_ID = 100
+  }
+
   override fun startWork(): ListenableFuture<Result> {
     Log.i(TAG, "Starting background upload worker")
 
+    val notificationChannel = NotificationChannel(
+      NOTIFICATION_CHANNEL_ID,
+      NOTIFICATION_CHANNEL_ID,
+      NotificationManager.IMPORTANCE_LOW
+    )
+    notificationManager.createNotificationChannel(notificationChannel)
+
     loader.ensureInitializationCompleteAsync(ctx, null, Handler(Looper.getMainLooper())) {
       engine = FlutterEngine(ctx)
 
@@ -82,6 +108,34 @@ class BackgroundWorker(context: Context, params: WorkerParameters) :
     flutterApi?.onAndroidUpload { handleHostResult(it) }
   }
 
+  // TODO: Move this to a separate NotificationManager class
+  override fun showNotification(title: String, content: String) {
+    val notification = NotificationCompat.Builder(applicationContext, NOTIFICATION_CHANNEL_ID)
+      .setSmallIcon(R.drawable.notification_icon)
+      .setOnlyAlertOnce(true)
+      .setOngoing(true)
+      .setTicker(title)
+      .setContentTitle(title)
+      .setContentText(content)
+      .build()
+
+    if (isIgnoringBatteryOptimizations()) {
+      foregroundFuture = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.UPSIDE_DOWN_CAKE) {
+        setForegroundAsync(
+          ForegroundInfo(
+            NOTIFICATION_ID,
+            notification,
+            FOREGROUND_SERVICE_TYPE_DATA_SYNC
+          )
+        )
+      } else {
+        setForegroundAsync(ForegroundInfo(NOTIFICATION_ID, notification))
+      }
+    } else {
+      notificationManager.notify(NOTIFICATION_ID, notification)
+    }
+  }
+
   override fun close() {
     if (isComplete) {
       return
@@ -95,6 +149,8 @@ class BackgroundWorker(context: Context, params: WorkerParameters) :
       }
     }
 
+    waitForForegroundPromotion()
+
     Handler(Looper.getMainLooper()).postDelayed({
       complete(Result.failure())
     }, 5000)
@@ -135,6 +191,32 @@ class BackgroundWorker(context: Context, params: WorkerParameters) :
     engine?.destroy()
     engine = null
     flutterApi = null
+    notificationManager.cancel(NOTIFICATION_ID)
+    waitForForegroundPromotion()
     completionHandler.set(success)
   }
+
+  /**
+   * Returns `true` if the app is ignoring battery optimizations
+   */
+  private fun isIgnoringBatteryOptimizations(): Boolean {
+    val powerManager = ctx.getSystemService(Context.POWER_SERVICE) as PowerManager
+    return powerManager.isIgnoringBatteryOptimizations(ctx.packageName)
+  }
+
+  /**
+   *  Calls to setForegroundAsync() that do not complete before completion of a ListenableWorker will signal an IllegalStateException
+   * https://android-review.googlesource.com/c/platform/frameworks/support/+/1262743
+   * Wait for a short period of time for the foreground promotion to complete before completing the worker
+   */
+  private fun waitForForegroundPromotion() {
+    val foregroundFuture = this.foregroundFuture
+    if (foregroundFuture != null && !foregroundFuture.isCancelled && !foregroundFuture.isDone) {
+      try {
+        foregroundFuture.get(500, TimeUnit.MILLISECONDS)
+      } catch (e: Exception) {
+        // ignored, there is nothing to be done
+      }
+    }
+  }
 }

mobile/android/app/src/main/kotlin/app/alextran/immich/connectivity/Connectivity.g.kt

@@ -0,0 +1,116 @@
+// Autogenerated from Pigeon (v26.0.0), do not edit directly.
+// See also: https://pub.dev/packages/pigeon
+@file:Suppress("UNCHECKED_CAST", "ArrayInDataClass")
+
+package app.alextran.immich.connectivity
+
+import android.util.Log
+import io.flutter.plugin.common.BasicMessageChannel
+import io.flutter.plugin.common.BinaryMessenger
+import io.flutter.plugin.common.EventChannel
+import io.flutter.plugin.common.MessageCodec
+import io.flutter.plugin.common.StandardMethodCodec
+import io.flutter.plugin.common.StandardMessageCodec
+import java.io.ByteArrayOutputStream
+import java.nio.ByteBuffer
+private object ConnectivityPigeonUtils {
+
+  fun wrapResult(result: Any?): List<Any?> {
+    return listOf(result)
+  }
+
+  fun wrapError(exception: Throwable): List<Any?> {
+    return if (exception is FlutterError) {
+      listOf(
+        exception.code,
+        exception.message,
+        exception.details
+      )
+    } else {
+      listOf(
+        exception.javaClass.simpleName,
+        exception.toString(),
+        "Cause: " + exception.cause + ", Stacktrace: " + Log.getStackTraceString(exception)
+      )
+    }
+  }
+}
+
+/**
+ * Error class for passing custom error details to Flutter via a thrown PlatformException.
+ * @property code The error code.
+ * @property message The error message.
+ * @property details The error details. Must be a datatype supported by the api codec.
+ */
+class FlutterError (
+  val code: String,
+  override val message: String? = null,
+  val details: Any? = null
+) : Throwable()
+
+enum class NetworkCapability(val raw: Int) {
+  CELLULAR(0),
+  WIFI(1),
+  VPN(2),
+  UNMETERED(3);
+
+  companion object {
+    fun ofRaw(raw: Int): NetworkCapability? {
+      return values().firstOrNull { it.raw == raw }
+    }
+  }
+}
+private open class ConnectivityPigeonCodec : StandardMessageCodec() {
+  override fun readValueOfType(type: Byte, buffer: ByteBuffer): Any? {
+    return when (type) {
+      129.toByte() -> {
+        return (readValue(buffer) as Long?)?.let {
+          NetworkCapability.ofRaw(it.toInt())
+        }
+      }
+      else -> super.readValueOfType(type, buffer)
+    }
+  }
+  override fun writeValue(stream: ByteArrayOutputStream, value: Any?)   {
+    when (value) {
+      is NetworkCapability -> {
+        stream.write(129)
+        writeValue(stream, value.raw)
+      }
+      else -> super.writeValue(stream, value)
+    }
+  }
+}
+
+/** Generated interface from Pigeon that represents a handler of messages from Flutter. */
+interface ConnectivityApi {
+  fun getCapabilities(): List<NetworkCapability>
+
+  companion object {
+    /** The codec used by ConnectivityApi. */
+    val codec: MessageCodec<Any?> by lazy {
+      ConnectivityPigeonCodec()
+    }
+    /** Sets up an instance of `ConnectivityApi` to handle messages through the `binaryMessenger`. */
+    @JvmOverloads
+    fun setUp(binaryMessenger: BinaryMessenger, api: ConnectivityApi?, messageChannelSuffix: String = "") {
+      val separatedMessageChannelSuffix = if (messageChannelSuffix.isNotEmpty()) ".$messageChannelSuffix" else ""
+      val taskQueue = binaryMessenger.makeBackgroundTaskQueue()
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.immich_mobile.ConnectivityApi.getCapabilities$separatedMessageChannelSuffix", codec, taskQueue)
+        if (api != null) {
+          channel.setMessageHandler { _, reply ->
+            val wrapped: List<Any?> = try {
+              listOf(api.getCapabilities())
+            } catch (exception: Throwable) {
+              ConnectivityPigeonUtils.wrapError(exception)
+            }
+            reply.reply(wrapped)
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+    }
+  }
+}

mobile/android/app/src/main/kotlin/app/alextran/immich/connectivity/ConnectivityApiImpl.kt

@@ -0,0 +1,39 @@
+package app.alextran.immich.connectivity
+
+import android.content.Context
+import android.net.ConnectivityManager
+import android.net.NetworkCapabilities
+import android.net.wifi.WifiManager
+
+class ConnectivityApiImpl(context: Context) : ConnectivityApi {
+  private val connectivityManager =
+    context.applicationContext.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
+  private val wifiManager =
+    context.applicationContext.getSystemService(Context.WIFI_SERVICE) as WifiManager
+
+  override fun getCapabilities(): List<NetworkCapability> {
+    val capabilities = connectivityManager.getNetworkCapabilities(connectivityManager.activeNetwork)
+      ?: return emptyList()
+
+    val hasWifi = capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI) ||
+      capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI_AWARE)
+    val hasCellular = capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)
+    val hasVpn = capabilities.hasTransport(NetworkCapabilities.TRANSPORT_VPN)
+    val isUnmetered = capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_METERED)
+
+    return buildList {
+      if (hasWifi) add(NetworkCapability.WIFI)
+      if (hasCellular) add(NetworkCapability.CELLULAR)
+      if (hasVpn) {
+        add(NetworkCapability.VPN)
+        if (!hasWifi && !hasCellular) {
+          if (wifiManager.isWifiEnabled) add(NetworkCapability.WIFI)
+          // If VPN is active, but neither WIFI nor CELLULAR is reported as active,
+          // assume CELLULAR if WIFI is not enabled
+          else add(NetworkCapability.CELLULAR)
+        }
+      }
+      if (isUnmetered) add(NetworkCapability.UNMETERED)
+    }
+  }
+}