Create a new system for fetching the intial batch of messages.

app/src/main/AndroidManifest.xml

@@ -493,7 +493,7 @@
     <service android:enabled="true" android:name="org.thoughtcrime.securesms.service.WebRtcCallService"/>
     <service android:enabled="true" android:name=".service.ApplicationMigrationService"/>
     <service android:enabled="true" android:exported="false" android:name=".service.KeyCachingService"/>
-    <service android:enabled="true" android:name=".service.IncomingMessageObserver$ForegroundService"/>
+    <service android:enabled="true" android:name=".messages.IncomingMessageObserver$ForegroundService"/>
 
     <service android:name=".service.QuickResponseService"
              android:permission="android.permission.SEND_RESPOND_VIA_MESSAGE"

app/src/main/java/org/thoughtcrime/securesms/ApplicationContext.java

@@ -50,6 +50,7 @@
 import org.thoughtcrime.securesms.logging.Log;
 import org.thoughtcrime.securesms.logging.PersistentLogger;
 import org.thoughtcrime.securesms.logging.SignalUncaughtExceptionHandler;
+import org.thoughtcrime.securesms.messages.InitialMessageRetriever;
 import org.thoughtcrime.securesms.migrations.ApplicationMigrations;
 import org.thoughtcrime.securesms.notifications.MessageNotifier;
 import org.thoughtcrime.securesms.notifications.NotificationChannels;
@@ -60,7 +61,7 @@
 import org.thoughtcrime.securesms.ringrtc.RingRtcLogger;
 import org.thoughtcrime.securesms.service.DirectoryRefreshListener;
 import org.thoughtcrime.securesms.service.ExpiringMessageManager;
-import org.thoughtcrime.securesms.service.IncomingMessageObserver;
+import org.thoughtcrime.securesms.messages.IncomingMessageObserver;
 import org.thoughtcrime.securesms.service.KeyCachingService;
 import org.thoughtcrime.securesms.service.LocalBackupListener;
 import org.thoughtcrime.securesms.service.RotateSenderCertificateListener;
@@ -153,6 +154,7 @@ public void onStart(@NonNull LifecycleOwner owner) {
     KeyCachingService.onAppForegrounded(this);
     ApplicationDependencies.getFrameRateTracker().begin();
     ApplicationDependencies.getMegaphoneRepository().onAppForegrounded();
+    catchUpOnMessages();
   }
 
   @Override
@@ -377,6 +379,36 @@ private void initializeCleanup() {
     });
   }
 
+  private void catchUpOnMessages() {
+    InitialMessageRetriever retriever = ApplicationDependencies.getInitialMessageRetriever();
+
+    if (retriever.isCaughtUp()) {
+      return;
+    }
+
+    SignalExecutors.UNBOUNDED.execute(() -> {
+      long startTime = System.currentTimeMillis();
+
+      switch (retriever.begin(TimeUnit.SECONDS.toMillis(60))) {
+        case SUCCESS:
+          Log.i(TAG, "Successfully caught up on messages. " + (System.currentTimeMillis() - startTime) + " ms");
+          break;
+        case FAILURE_TIMEOUT:
+          Log.w(TAG, "Did not finish catching up due to a timeout. " + (System.currentTimeMillis() - startTime) + " ms");
+          break;
+        case FAILURE_ERROR:
+          Log.w(TAG, "Did not finish catching up due to an error. " + (System.currentTimeMillis() - startTime) + " ms");
+          break;
+        case SKIPPED_ALREADY_CAUGHT_UP:
+          Log.i(TAG, "Already caught up. " + (System.currentTimeMillis() - startTime) + " ms");
+          break;
+        case SKIPPED_ALREADY_RUNNING:
+          Log.i(TAG, "Already in the process of catching up. " + (System.currentTimeMillis() - startTime) + " ms");
+          break;
+      }
+    });
+  }
+
   @Override
   protected void attachBaseContext(Context base) {
     super.attachBaseContext(DynamicLanguageContextWrapper.updateContext(base, TextSecurePreferences.getLanguage(base)));

app/src/main/java/org/thoughtcrime/securesms/dependencies/ApplicationDependencies.java

@@ -5,17 +5,18 @@
 import androidx.annotation.NonNull;
 
 import org.thoughtcrime.securesms.BuildConfig;
-import org.thoughtcrime.securesms.IncomingMessageProcessor;
-import org.thoughtcrime.securesms.gcm.MessageRetriever;
+import org.thoughtcrime.securesms.messages.IncomingMessageProcessor;
+import org.thoughtcrime.securesms.messages.BackgroundMessageRetriever;
 import org.thoughtcrime.securesms.groups.GroupsV2AuthorizationMemoryValueCache;
 import org.thoughtcrime.securesms.groups.v2.processing.GroupsV2StateProcessor;
 import org.thoughtcrime.securesms.jobmanager.JobManager;
 import org.thoughtcrime.securesms.keyvalue.KeyValueStore;
 import org.thoughtcrime.securesms.keyvalue.SignalStore;
 import org.thoughtcrime.securesms.megaphone.MegaphoneRepository;
+import org.thoughtcrime.securesms.messages.InitialMessageRetriever;
 import org.thoughtcrime.securesms.push.SignalServiceNetworkAccess;
 import org.thoughtcrime.securesms.recipients.LiveRecipientCache;
-import org.thoughtcrime.securesms.service.IncomingMessageObserver;
+import org.thoughtcrime.securesms.messages.IncomingMessageObserver;
 import org.thoughtcrime.securesms.util.EarlyMessageCache;
 import org.thoughtcrime.securesms.util.FeatureFlags;
 import org.thoughtcrime.securesms.util.FrameRateTracker;
@@ -45,7 +46,7 @@ public class ApplicationDependencies {
   private static SignalServiceMessageSender   messageSender;
   private static SignalServiceMessageReceiver messageReceiver;
   private static IncomingMessageProcessor     incomingMessageProcessor;
-  private static MessageRetriever             messageRetriever;
+  private static BackgroundMessageRetriever   backgroundMessageRetriever;
   private static LiveRecipientCache           recipientCache;
   private static JobManager                   jobManager;
   private static FrameRateTracker             frameRateTracker;
@@ -55,6 +56,7 @@ public class ApplicationDependencies {
   private static GroupsV2StateProcessor       groupsV2StateProcessor;
   private static GroupsV2Operations           groupsV2Operations;
   private static EarlyMessageCache            earlyMessageCache;
+  private static InitialMessageRetriever      initialMessageRetriever;
 
   public static synchronized void init(@NonNull Application application, @NonNull Provider provider) {
     if (ApplicationDependencies.application != null || ApplicationDependencies.provider != null) {
@@ -164,14 +166,14 @@ public static synchronized void resetSignalServiceMessageReceiver() {
     return incomingMessageProcessor;
   }
 
-  public static synchronized @NonNull MessageRetriever getMessageRetriever() {
+  public static synchronized @NonNull BackgroundMessageRetriever getBackgroundMessageRetriever() {
     assertInitialization();
 
-    if (messageRetriever == null) {
-      messageRetriever = provider.provideMessageRetriever();
+    if (backgroundMessageRetriever == null) {
+      backgroundMessageRetriever = provider.provideBackgroundMessageRetriever();
     }
 
-    return messageRetriever;
+    return backgroundMessageRetriever;
   }
 
   public static synchronized @NonNull LiveRecipientCache getRecipientCache() {
@@ -234,6 +236,16 @@ public static synchronized void resetSignalServiceMessageReceiver() {
     return earlyMessageCache;
   }
 
+  public static synchronized @NonNull InitialMessageRetriever getInitialMessageRetriever() {
+    assertInitialization();
+
+    if (initialMessageRetriever == null) {
+      initialMessageRetriever = provider.provideInitialMessageRetriever();
+    }
+
+    return initialMessageRetriever;
+  }
+
   private static void assertInitialization() {
     if (application == null || provider == null) {
       throw new UninitializedException();
@@ -247,13 +259,14 @@ public interface Provider {
     @NonNull SignalServiceMessageReceiver provideSignalServiceMessageReceiver();
     @NonNull SignalServiceNetworkAccess provideSignalServiceNetworkAccess();
     @NonNull IncomingMessageProcessor provideIncomingMessageProcessor();
-    @NonNull MessageRetriever provideMessageRetriever();
+    @NonNull BackgroundMessageRetriever provideBackgroundMessageRetriever();
     @NonNull LiveRecipientCache provideRecipientCache();
     @NonNull JobManager provideJobManager();
     @NonNull FrameRateTracker provideFrameRateTracker();
     @NonNull KeyValueStore provideKeyValueStore();
     @NonNull MegaphoneRepository provideMegaphoneRepository();
     @NonNull EarlyMessageCache provideEarlyMessageCache();
+    @NonNull InitialMessageRetriever provideInitialMessageRetriever();
   }
 
   private static class UninitializedException extends IllegalStateException {

app/src/main/java/org/thoughtcrime/securesms/dependencies/ApplicationDependencyProvider.java

@@ -7,11 +7,11 @@
 
 import org.greenrobot.eventbus.EventBus;
 import org.thoughtcrime.securesms.BuildConfig;
-import org.thoughtcrime.securesms.IncomingMessageProcessor;
+import org.thoughtcrime.securesms.messages.IncomingMessageProcessor;
 import org.thoughtcrime.securesms.crypto.storage.SignalProtocolStoreImpl;
 import org.thoughtcrime.securesms.database.DatabaseFactory;
 import org.thoughtcrime.securesms.events.ReminderUpdateEvent;
-import org.thoughtcrime.securesms.gcm.MessageRetriever;
+import org.thoughtcrime.securesms.messages.BackgroundMessageRetriever;
 import org.thoughtcrime.securesms.jobmanager.JobManager;
 import org.thoughtcrime.securesms.jobmanager.JobMigrator;
 import org.thoughtcrime.securesms.jobmanager.impl.JsonDataSerializer;
@@ -20,10 +20,11 @@
 import org.thoughtcrime.securesms.keyvalue.KeyValueStore;
 import org.thoughtcrime.securesms.logging.Log;
 import org.thoughtcrime.securesms.megaphone.MegaphoneRepository;
+import org.thoughtcrime.securesms.messages.InitialMessageRetriever;
 import org.thoughtcrime.securesms.push.SecurityEventListener;
 import org.thoughtcrime.securesms.push.SignalServiceNetworkAccess;
 import org.thoughtcrime.securesms.recipients.LiveRecipientCache;
-import org.thoughtcrime.securesms.service.IncomingMessageObserver;
+import org.thoughtcrime.securesms.messages.IncomingMessageObserver;
 import org.thoughtcrime.securesms.util.AlarmSleepTimer;
 import org.thoughtcrime.securesms.util.EarlyMessageCache;
 import org.thoughtcrime.securesms.util.FeatureFlags;
@@ -111,8 +112,8 @@ public ApplicationDependencyProvider(@NonNull Application context, @NonNull Sign
   }
 
   @Override
-  public @NonNull MessageRetriever provideMessageRetriever() {
-    return new MessageRetriever();
+  public @NonNull BackgroundMessageRetriever provideBackgroundMessageRetriever() {
+    return new BackgroundMessageRetriever();
   }
 
   @Override
@@ -152,6 +153,11 @@ public ApplicationDependencyProvider(@NonNull Application context, @NonNull Sign
     return new EarlyMessageCache();
   }
 
+  @Override
+  public @NonNull InitialMessageRetriever provideInitialMessageRetriever() {
+    return new InitialMessageRetriever();
+  }
+
   private static class DynamicCredentialsProvider implements CredentialsProvider {
 
     private final Context context;

app/src/main/java/org/thoughtcrime/securesms/gcm/FcmFetchService.java

@@ -12,6 +12,8 @@
 import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
 import org.thoughtcrime.securesms.jobs.PushNotificationReceiveJob;
 import org.thoughtcrime.securesms.logging.Log;
+import org.thoughtcrime.securesms.messages.BackgroundMessageRetriever;
+import org.thoughtcrime.securesms.messages.RestStrategy;
 import org.thoughtcrime.securesms.util.concurrent.SerialMonoLifoExecutor;
 import org.thoughtcrime.securesms.util.concurrent.SignalExecutors;
 
@@ -68,8 +70,8 @@ public void onDestroy() {
   }
 
   private void fetch() {
-    MessageRetriever retriever = ApplicationDependencies.getMessageRetriever();
-    boolean          success   = retriever.retrieveMessages(this, new RestStrategy(), new RestStrategy());
+    BackgroundMessageRetriever retriever = ApplicationDependencies.getBackgroundMessageRetriever();
+    boolean                    success   = retriever.retrieveMessages(this, new RestStrategy(), new RestStrategy());
 
     if (success) {
       Log.i(TAG, "Successfully retrieved messages.");

app/src/main/java/org/thoughtcrime/securesms/gcm/FcmJobService.java

@@ -11,6 +11,8 @@
 
 import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
 import org.thoughtcrime.securesms.logging.Log;
+import org.thoughtcrime.securesms.messages.BackgroundMessageRetriever;
+import org.thoughtcrime.securesms.messages.RestStrategy;
 import org.thoughtcrime.securesms.util.ServiceUtil;
 import org.thoughtcrime.securesms.util.TextSecurePreferences;
 import org.thoughtcrime.securesms.util.concurrent.SignalExecutors;
@@ -39,15 +41,15 @@ public static void schedule(@NonNull Context context) {
   public boolean onStartJob(JobParameters params) {
     Log.d(TAG, "onStartJob()");
 
-    if (MessageRetriever.shouldIgnoreFetch(this)) {
+    if (BackgroundMessageRetriever.shouldIgnoreFetch(this)) {
       Log.i(TAG, "App is foregrounded. No need to run.");
       return false;
     }
 
     SignalExecutors.UNBOUNDED.execute(() -> {
-      Context          context   = getApplicationContext();
-      MessageRetriever retriever = ApplicationDependencies.getMessageRetriever();
-      boolean          success   = retriever.retrieveMessages(context, new RestStrategy(), new RestStrategy());
+      Context                    context   = getApplicationContext();
+      BackgroundMessageRetriever retriever = ApplicationDependencies.getBackgroundMessageRetriever();
+      boolean                    success   = retriever.retrieveMessages(context, new RestStrategy(), new RestStrategy());
 
       if (success) {
         Log.i(TAG, "Successfully retrieved messages.");

app/src/main/java/org/thoughtcrime/securesms/jobs/PushNotificationReceiveJob.java

@@ -4,8 +4,8 @@
 import androidx.annotation.NonNull;
 
 import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
-import org.thoughtcrime.securesms.gcm.MessageRetriever;
-import org.thoughtcrime.securesms.gcm.RestStrategy;
+import org.thoughtcrime.securesms.messages.BackgroundMessageRetriever;
+import org.thoughtcrime.securesms.messages.RestStrategy;
 import org.thoughtcrime.securesms.jobmanager.Data;
 import org.thoughtcrime.securesms.jobmanager.Job;
 import org.thoughtcrime.securesms.jobmanager.impl.NetworkConstraint;
@@ -46,8 +46,8 @@ private PushNotificationReceiveJob(@NonNull Job.Parameters parameters) {
 
   @Override
   public void onRun() throws IOException {
-    MessageRetriever retriever = ApplicationDependencies.getMessageRetriever();
-    boolean          result    = retriever.retrieveMessages(context, new RestStrategy());
+    BackgroundMessageRetriever retriever = ApplicationDependencies.getBackgroundMessageRetriever();
+    boolean                    result    = retriever.retrieveMessages(context, new RestStrategy());
 
     if (result) {
       Log.i(TAG, "Successfully pulled messages.");