Subscription sync service running every 24 hours to sync if necessary the user's premium subscription state between NewsBlur and Play Store.

clients/android/NewsBlur/AndroidManifest.xml

@@ -147,6 +147,10 @@
             android:permission="android.permission.BIND_JOB_SERVICE" />
         <service android:name=".widget.WidgetRemoteViewsService"
             android:permission="android.permission.BIND_REMOTEVIEWS" />
+        <service
+            android:name=".service.SubscriptionSyncService"
+            android:permission="android.permission.BIND_JOB_SERVICE"
+            android:exported="false" />
 
         <receiver android:name=".service.BootReceiver"
             android:exported="true">

clients/android/NewsBlur/src/com/newsblur/NbApplication.kt

@@ -1,15 +1,20 @@
 package com.newsblur
 
 import android.app.Application
+import android.app.job.JobScheduler
+import android.content.Context
 import androidx.lifecycle.DefaultLifecycleObserver
 import androidx.lifecycle.LifecycleOwner
 import androidx.lifecycle.ProcessLifecycleOwner
+import com.newsblur.service.SubscriptionSyncService
+import com.newsblur.util.Log
 
 class NbApplication : Application(), DefaultLifecycleObserver {
 
     override fun onCreate() {
         super<Application>.onCreate()
         ProcessLifecycleOwner.get().lifecycle.addObserver(this)
+        scheduleSubscriptionSync()
     }
 
     override fun onStart(owner: LifecycleOwner) {
@@ -22,6 +27,15 @@ class NbApplication : Application(), DefaultLifecycleObserver {
         isAppForeground = false
     }
 
+    private fun scheduleSubscriptionSync() {
+        val jobScheduler = getSystemService(Context.JOB_SCHEDULER_SERVICE) as JobScheduler
+        val scheduledSubscriptionJob = jobScheduler.allPendingJobs.find { it.id == SubscriptionSyncService.JOB_ID }
+        if (scheduledSubscriptionJob == null) {
+            val result: Int = jobScheduler.schedule(SubscriptionSyncService.createJobInfo(this))
+            Log.d(this, "Scheduled subscription result: ${if (result == JobScheduler.RESULT_FAILURE) "failed" else "completed"}")
+        }
+    }
+
     companion object {
 
         @JvmStatic

clients/android/NewsBlur/src/com/newsblur/service/SubscriptionSyncService.kt

@@ -0,0 +1,55 @@
+package com.newsblur.service
+
+import android.app.job.JobInfo
+import android.app.job.JobParameters
+import android.app.job.JobService
+import android.content.ComponentName
+import android.content.Context
+import com.newsblur.subscription.SubscriptionManagerImpl
+import com.newsblur.util.AppConstants
+import com.newsblur.util.Log
+import com.newsblur.util.NBScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+
+/**
+ * Service to sync user subscription with NewsBlur backend.
+ *
+ * Mostly interested in handling the state where there is an active
+ * subscription in Play Store but NewsBlur doesn't know about it.
+ * This could occur when the user has renewed the subscription
+ * via Play Store.
+ */
+class SubscriptionSyncService : JobService() {
+
+    override fun onStartJob(params: JobParameters?): Boolean {
+        Log.d(this, "onStartJob")
+        NBScope.launch(Dispatchers.Default) {
+            val subscriptionManager = SubscriptionManagerImpl(this@SubscriptionSyncService, this)
+            val job = subscriptionManager.syncActiveSubscription()
+            job.invokeOnCompletion {
+                Log.d(this, "sync active subscription completed.")
+                // manually trigger jobFinished after work is done
+                jobFinished(params, false)
+            }
+        }
+
+        return true // returning true due to background thread work
+    }
+
+    override fun onStopJob(params: JobParameters?): Boolean = false
+
+    companion object {
+        const val JOB_ID = 2021
+
+        fun createJobInfo(context: Context): JobInfo = JobInfo.Builder(JOB_ID,
+                ComponentName(context, SubscriptionSyncService::class.java))
+                .apply {
+                    // sync every 24 hours
+                    setPeriodic(AppConstants.BG_SUBSCRIPTION_SYNC_CYCLE_MILLIS)
+                    setRequiredNetworkType(JobInfo.NETWORK_TYPE_ANY)
+                    setBackoffCriteria(JobInfo.DEFAULT_INITIAL_BACKOFF_MILLIS, JobInfo.BACKOFF_POLICY_EXPONENTIAL)
+                    setPersisted(true)
+                }.build()
+    }
+}

clients/android/NewsBlur/src/com/newsblur/subscription/SubscriptionManager.kt

@@ -25,6 +25,7 @@ import kotlinx.coroutines.CompletableDeferred
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Deferred
 import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import java.text.DateFormat
@@ -57,7 +58,7 @@ interface SubscriptionManager {
     /**
      * Sync subscription state between NewsBlur and Play Store.
      */
-    fun syncActiveSubscription()
+    fun syncActiveSubscription(): Job
 
     /**
      * Notify backend of active Play Store subscription.
@@ -159,7 +160,7 @@ class SubscriptionManagerImpl(
     }
 
     override fun syncSubscriptionState() {
-        scope.launch {
+        scope.launch(Dispatchers.Default) {
             if (hasActiveSubscription()) syncActiveSubscription()
             else syncAvailableSubscription()
         }
@@ -173,21 +174,21 @@ class SubscriptionManagerImpl(
         billingClient.launchBillingFlow(activity, billingFlowParams)
     }
 
-    override fun syncActiveSubscription() {
+    override fun syncActiveSubscription() = scope.launch(Dispatchers.Default) {
-        scope.launch(Dispatchers.Default) {
+        val hasNewsBlurSubscription = PrefsUtils.getIsPremium(context)
-            val hasNewsBlurSubscription = PrefsUtils.getIsPremium(context)
+        val activePlayStoreSubscription = getActiveSubscriptionAsync().await()
-            val activePlayStoreSubscription = getActiveSubscriptionAsync().await()
 
-            if (hasNewsBlurSubscription || activePlayStoreSubscription != null) {
+        if (hasNewsBlurSubscription || activePlayStoreSubscription != null) {
+            listener?.let {
                 val renewalString: String? = getRenewalMessage(activePlayStoreSubscription)
                 withContext(Dispatchers.Main) {
-                    listener?.onActiveSubscription(renewalString)
+                    it.onActiveSubscription(renewalString)
                 }
             }
+        }
 
-            if (!hasNewsBlurSubscription && activePlayStoreSubscription != null) {
+        if (!hasNewsBlurSubscription && activePlayStoreSubscription != null) {
-                saveReceipt(activePlayStoreSubscription)
+            saveReceipt(activePlayStoreSubscription)
-            }
         }
     }
 
@@ -210,15 +211,13 @@ class SubscriptionManagerImpl(
         )
     }
 
-    private suspend fun syncAvailableSubscription() {
+    private suspend fun syncAvailableSubscription() = scope.launch(Dispatchers.Default) {
-        scope.launch(Dispatchers.Default) {
+        val skuDetails = getAvailableSubscriptionAsync().await()
-            val skuDetails = getAvailableSubscriptionAsync().await()
+        withContext(Dispatchers.Main) {
-            withContext(Dispatchers.Main) {
+            skuDetails?.let {
-                skuDetails?.let {
+                Log.d(this, it.toString())
-                    Log.d(this, it.toString())
+                listener?.onAvailableSubscription(it)
-                    listener?.onAvailableSubscription(it)
+            } ?: listener?.onBillingConnectionError()
-                } ?: listener?.onBillingConnectionError()
-            }
         }
     }
 

clients/android/NewsBlur/src/com/newsblur/util/AppConstants.java

@@ -41,6 +41,9 @@ public class AppConstants {
     // to account for the fact that it is approximate, and missing a cycle is bad.
     public static final long BG_SERVICE_CYCLE_MILLIS = AUTO_SYNC_TIME_MILLIS + 30L * 1000L;
 
+    // how often to trigger the job scheduler to sync subscription state.
+    public static final long BG_SUBSCRIPTION_SYNC_CYCLE_MILLIS = 24L * 60 * 60 * 1000L;
+
     // how many total attemtps to make at a single API call
     public static final int MAX_API_TRIES = 3;