Add experiment to coalesce android notifications

service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java

@@ -647,7 +647,7 @@ public class WhisperServerService extends Application<WhisperServerConfiguration
     PushNotificationScheduler pushNotificationScheduler = new PushNotificationScheduler(pushSchedulerCluster,
         apnSender, fcmSender, accountsManager, 0, 0);
     PushNotificationManager pushNotificationManager =
-        new PushNotificationManager(accountsManager, apnSender, fcmSender, pushNotificationScheduler);
+        new PushNotificationManager(accountsManager, apnSender, fcmSender, pushNotificationScheduler, experimentEnrollmentManager);
     WebSocketConnectionEventManager webSocketConnectionEventManager =
         new WebSocketConnectionEventManager(accountsManager, pushNotificationManager, messagesCluster, clientEventExecutor, asyncOperationQueueingExecutor);
     RateLimiters rateLimiters = RateLimiters.createAndValidate(config.getLimitsConfiguration(),

service/src/main/java/org/whispersystems/textsecuregcm/push/PushNotificationManager.java

@@ -17,6 +17,7 @@ import java.util.function.BiConsumer;
 import org.apache.commons.lang3.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.whispersystems.textsecuregcm.experiment.ExperimentEnrollmentManager;
 import org.whispersystems.textsecuregcm.storage.Account;
 import org.whispersystems.textsecuregcm.storage.AccountsManager;
 import org.whispersystems.textsecuregcm.storage.Device;
@@ -28,6 +29,9 @@ public class PushNotificationManager {
   private final APNSender apnSender;
   private final FcmSender fcmSender;
   private final PushNotificationScheduler pushNotificationScheduler;
+  private final ExperimentEnrollmentManager experimentEnrollmentManager;
+
+  private static final String SCHEDULE_LOW_URGENCY_FCM_PUSH_EXPERIMENT = "scheduleLowUregencyFcmPush";
 
   private static final String SENT_NOTIFICATION_COUNTER_NAME = name(PushNotificationManager.class, "sentPushNotification");
   private static final String FAILED_NOTIFICATION_COUNTER_NAME = name(PushNotificationManager.class, "failedPushNotification");
@@ -38,12 +42,14 @@ public class PushNotificationManager {
   public PushNotificationManager(final AccountsManager accountsManager,
       final APNSender apnSender,
       final FcmSender fcmSender,
-      final PushNotificationScheduler pushNotificationScheduler) {
+      final PushNotificationScheduler pushNotificationScheduler,
+      final ExperimentEnrollmentManager experimentEnrollmentManager) {
 
     this.accountsManager = accountsManager;
     this.apnSender = apnSender;
     this.fcmSender = fcmSender;
     this.pushNotificationScheduler = pushNotificationScheduler;
+    this.experimentEnrollmentManager = experimentEnrollmentManager;
   }
 
   public CompletableFuture<Optional<SendPushNotificationResult>> sendNewMessageNotification(final Account destination, final byte destinationDeviceId, final boolean urgent) throws NotPushRegisteredException {
@@ -101,9 +107,9 @@ public class PushNotificationManager {
 
   @VisibleForTesting
   CompletableFuture<Optional<SendPushNotificationResult>> sendNotification(final PushNotification pushNotification) {
-    if (pushNotification.tokenType() == PushNotification.TokenType.APN && !pushNotification.urgent()) {
+    if (shouldScheduleNotification(pushNotification)) {
-      // APNs imposes a per-device limit on background push notifications; schedule a notification for some time in the
+      // Schedule a notification for some time in the future (possibly even now!) rather than sending a notification
-      // future (possibly even now!) rather than sending a notification directly
+      // directly
       return pushNotificationScheduler
           .scheduleBackgroundNotification(pushNotification.tokenType(), pushNotification.destination(), pushNotification.destinationDevice())
           .whenComplete(logErrors())
@@ -150,6 +156,16 @@ public class PushNotificationManager {
         .thenApply(Optional::of);
   }
 
+  private boolean shouldScheduleNotification(final PushNotification pushNotification) {
+    return !pushNotification.urgent() && switch (pushNotification.tokenType()) {
+      // APNs imposes a per-device limit on background push notifications
+      case APN -> true;
+      case FCM -> experimentEnrollmentManager.isEnrolled(
+          pushNotification.destination().getUuid(),
+          SCHEDULE_LOW_URGENCY_FCM_PUSH_EXPERIMENT);
+    };
+  }
+
   private static <T> BiConsumer<T, Throwable> logErrors() {
     return (ignored, throwable) -> {
       if (throwable != null) {

service/src/main/java/org/whispersystems/textsecuregcm/workers/CommandDependencies.java

@@ -33,6 +33,7 @@ import org.whispersystems.textsecuregcm.backup.Cdn3RemoteStorageManager;
 import org.whispersystems.textsecuregcm.configuration.dynamic.DynamicConfiguration;
 import org.whispersystems.textsecuregcm.controllers.SecureStorageController;
 import org.whispersystems.textsecuregcm.controllers.SecureValueRecovery2Controller;
+import org.whispersystems.textsecuregcm.experiment.ExperimentEnrollmentManager;
 import org.whispersystems.textsecuregcm.experiment.PushNotificationExperimentSamples;
 import org.whispersystems.textsecuregcm.limits.RateLimiters;
 import org.whispersystems.textsecuregcm.metrics.MicrometerAwsSdkMetricPublisher;
@@ -113,6 +114,8 @@ record CommandDependencies(
         new DynamicConfigurationManager<>(
             configuration.getDynamicConfig().build(awsCredentialsProvider, dynamicConfigurationExecutor), DynamicConfiguration.class);
     dynamicConfigurationManager.start();
+    final ExperimentEnrollmentManager experimentEnrollmentManager =
+        new ExperimentEnrollmentManager(dynamicConfigurationManager);
 
     final ClientResources.Builder redisClientResourcesBuilder = ClientResources.builder();
 
@@ -271,8 +274,8 @@ record CommandDependencies(
     FcmSender fcmSender = new FcmSender(fcmSenderExecutor, configuration.getFcmConfiguration().credentials().value());
     PushNotificationScheduler pushNotificationScheduler = new PushNotificationScheduler(pushSchedulerCluster,
         apnSender, fcmSender, accountsManager, 0, 0);
-    PushNotificationManager pushNotificationManager =
+    PushNotificationManager pushNotificationManager = new PushNotificationManager(accountsManager,
-        new PushNotificationManager(accountsManager, apnSender, fcmSender, pushNotificationScheduler);
+        apnSender, fcmSender, pushNotificationScheduler, experimentEnrollmentManager);
     PushNotificationExperimentSamples pushNotificationExperimentSamples =
         new PushNotificationExperimentSamples(dynamoDbAsyncClient,
             configuration.getDynamoDbTables().getPushNotificationExperimentSamples().getTableName(),

service/src/test/java/org/whispersystems/textsecuregcm/push/PushNotificationManagerTest.java

@@ -23,6 +23,8 @@ import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
+import org.junitpioneer.jupiter.cartesian.CartesianTest;
+import org.whispersystems.textsecuregcm.experiment.ExperimentEnrollmentManager;
 import org.whispersystems.textsecuregcm.storage.Account;
 import org.whispersystems.textsecuregcm.storage.AccountsManager;
 import org.whispersystems.textsecuregcm.storage.Device;
@@ -34,6 +36,7 @@ class PushNotificationManagerTest {
   private APNSender apnSender;
   private FcmSender fcmSender;
   private PushNotificationScheduler pushNotificationScheduler;
+  private ExperimentEnrollmentManager experimentEnrollmentManager;
 
   private PushNotificationManager pushNotificationManager;
 
@@ -43,11 +46,12 @@ class PushNotificationManagerTest {
     apnSender = mock(APNSender.class);
     fcmSender = mock(FcmSender.class);
     pushNotificationScheduler = mock(PushNotificationScheduler.class);
+    experimentEnrollmentManager = mock(ExperimentEnrollmentManager.class);
 
     AccountsHelper.setupMockUpdate(accountsManager);
 
-    pushNotificationManager =
+    pushNotificationManager = new PushNotificationManager(accountsManager, apnSender, fcmSender,
-        new PushNotificationManager(accountsManager, apnSender, fcmSender, pushNotificationScheduler);
+        pushNotificationScheduler, experimentEnrollmentManager);
   }
 
   @ParameterizedTest
@@ -155,36 +159,48 @@ class PushNotificationManagerTest {
     verifyNoInteractions(pushNotificationScheduler);
   }
 
-  @ParameterizedTest
+  @CartesianTest
-  @ValueSource(booleans = {true, false})
+  void testSendOrScheduleNotification(
-  void testSendNotificationApn(final boolean urgent) {
+      @CartesianTest.Enum(PushNotification.TokenType.class) PushNotification.TokenType tokenType,
+      @CartesianTest.Values(booleans = {false, true}) final boolean urgent,
+      @CartesianTest.Values(booleans = {false, true}) final boolean inExperiment) {
+
+    final boolean expectSchedule = !urgent && (tokenType == PushNotification.TokenType.APN || inExperiment);
+
     final Account account = mock(Account.class);
     final Device device = mock(Device.class);
+    final UUID aci = UUID.randomUUID();
 
     when(device.getId()).thenReturn(Device.PRIMARY_ID);
     when(account.getDevice(Device.PRIMARY_ID)).thenReturn(Optional.of(device));
+    when(account.getUuid()).thenReturn(aci);
+
+    when(experimentEnrollmentManager.isEnrolled(aci, PushNotificationManager.SCHEDULE_LOW_URGENCY_FCM_PUSH_EXPERIMENT))
+        .thenReturn(inExperiment);
 
     final PushNotification pushNotification = new PushNotification(
-        "token", PushNotification.TokenType.APN, PushNotification.NotificationType.NOTIFICATION, null, account, device, urgent);
+        "token", tokenType, PushNotification.NotificationType.NOTIFICATION, null, account, device, urgent);
 
-    when(apnSender.sendNotification(pushNotification))
+    final PushNotificationSender sender = switch (tokenType) {
+      case FCM -> fcmSender;
+      case APN -> apnSender;
+    };
+    when(sender.sendNotification(pushNotification))
         .thenReturn(CompletableFuture.completedFuture(new SendPushNotificationResult(true, Optional.empty(), false, Optional.empty())));
 
-    if (!urgent) {
+    if (expectSchedule) {
-      when(pushNotificationScheduler.scheduleBackgroundNotification(PushNotification.TokenType.APN, account, device))
+      when(pushNotificationScheduler.scheduleBackgroundNotification(tokenType, account, device))
           .thenReturn(CompletableFuture.completedFuture(null));
     }
 
     pushNotificationManager.sendNotification(pushNotification);
 
-    verifyNoInteractions(fcmSender);
+    if (!expectSchedule) {
-
+      verify(sender).sendNotification(pushNotification);
-    if (urgent) {
-      verify(apnSender).sendNotification(pushNotification);
       verifyNoInteractions(pushNotificationScheduler);
     } else {
-      verifyNoInteractions(apnSender);
+      verifyNoInteractions(sender);
-      verify(pushNotificationScheduler).scheduleBackgroundNotification(PushNotification.TokenType.APN, account, device);
+      verify(pushNotificationScheduler).scheduleBackgroundNotification(tokenType, account, device);
     }
   }