Attempt to fix potential ANR

In onReceive in NotificationAlarmReceiver onBlocking() was used which
could potentially take too much time and cause an ANR. This PR changes
the onBlocking() call to instead use the goAsync() API so that the
onReceive method can return immediately.

3 files changed, 30 insertions, 5 deletions

diff --git a/android/app/src/main/kotlin/net/mullvad/mullvadvpn/receiver/NotificationAlarmReceiver.kt b/android/app/src/main/kotlin/net/mullvad/mullvadvpn/receiver/NotificationAlarmReceiver.kt
index 7b8ab4e04a..49bd290230 100644
--- a/android/app/src/main/kotlin/net/mullvad/mullvadvpn/receiver/NotificationAlarmReceiver.kt
+++ b/android/app/src/main/kotlin/net/mullvad/mullvadvpn/receiver/NotificationAlarmReceiver.kt
@@ -6,9 +6,9 @@ import android.content.Intent
 import co.touchlab.kermit.Logger
 import java.time.Duration
 import java.time.ZonedDateTime
-import kotlinx.coroutines.runBlocking
 import net.mullvad.mullvadvpn.service.notifications.accountexpiry.AccountExpiryNotificationProvider
 import net.mullvad.mullvadvpn.usecase.ScheduleNotificationAlarmUseCase
+import net.mullvad.mullvadvpn.util.goAsync
 import net.mullvad.mullvadvpn.util.serializable
 import org.koin.core.component.KoinComponent
 import org.koin.core.component.inject
@@ -28,8 +28,9 @@ class NotificationAlarmReceiver : BroadcastReceiver(), KoinComponent {
         Logger.d("Account expiry alarm triggered")
         val untilExpiry = Duration.between(ZonedDateTime.now(), expiry)
 
-        runBlocking {
-            notificationProvider.showNotification(untilExpiry)
+        notificationProvider.showNotification(untilExpiry)
+
+        goAsync {
             // Only schedule the next alarm if we still have time left on the account.
             if (context != null && expiry > ZonedDateTime.now()) {
                 scheduleNotificationAlarmUseCase(context = context, accountExpiry = expiry)
diff --git a/android/app/src/main/kotlin/net/mullvad/mullvadvpn/util/BroadcastReceiverExtensions.kt b/android/app/src/main/kotlin/net/mullvad/mullvadvpn/util/BroadcastReceiverExtensions.kt
new file mode 100644
index 0000000000..9d835a96a7
--- /dev/null
+++ b/android/app/src/main/kotlin/net/mullvad/mullvadvpn/util/BroadcastReceiverExtensions.kt
@@ -0,0 +1,23 @@
+package net.mullvad.mullvadvpn.util
+
+import android.content.BroadcastReceiver
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.DelicateCoroutinesApi
+import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.launch
+
+@OptIn(DelicateCoroutinesApi::class)
+fun BroadcastReceiver.goAsync(
+    coroutineScope: CoroutineScope = GlobalScope,
+    block: suspend () -> Unit,
+) {
+    val result = goAsync()
+    coroutineScope.launch {
+        try {
+            block()
+        } finally {
+            // Always call finish(), even if the coroutineScope was cancelled
+            result.finish()
+        }
+    }
+}
diff --git a/android/service/src/main/kotlin/net/mullvad/mullvadvpn/service/notifications/accountexpiry/AccountExpiryNotificationProvider.kt b/android/service/src/main/kotlin/net/mullvad/mullvadvpn/service/notifications/accountexpiry/AccountExpiryNotificationProvider.kt
index 776ce47960..0be99896c9 100644
--- a/android/service/src/main/kotlin/net/mullvad/mullvadvpn/service/notifications/accountexpiry/AccountExpiryNotificationProvider.kt
+++ b/android/service/src/main/kotlin/net/mullvad/mullvadvpn/service/notifications/accountexpiry/AccountExpiryNotificationProvider.kt
@@ -20,7 +20,7 @@ class AccountExpiryNotificationProvider(private val channelId: NotificationChann
     override val notifications: Flow<NotificationUpdate<Notification.AccountExpiry>>
         get() = notificationChannel.receiveAsFlow()
 
-    suspend fun showNotification(durationUntilExpiry: Duration) {
+    fun showNotification(durationUntilExpiry: Duration) {
         val notification =
             Notification.AccountExpiry(
                 channelId = channelId,
@@ -29,7 +29,8 @@ class AccountExpiryNotificationProvider(private val channelId: NotificationChann
             )
 
         val notificationUpdate = NotificationUpdate.Notify(NOTIFICATION_ID, notification)
-        notificationChannel.send(notificationUpdate)
+        // Always succeeds because the channel is conflated.
+        notificationChannel.trySend(notificationUpdate)
     }
 
     suspend fun cancelNotification() {