Retire the explicit "handle new message available" system in favor of implicit presence-on-insert values

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

@@ -654,8 +654,7 @@ public class WhisperServerService extends Application<WhisperServerConfiguration
 
     final AccountAuthenticator accountAuthenticator = new AccountAuthenticator(accountsManager);
 
-    final MessageSender messageSender =
+    final MessageSender messageSender = new MessageSender(messagesManager, pushNotificationManager);
-        new MessageSender(pubSubClientEventManager, messagesManager, pushNotificationManager);
     final ReceiptSender receiptSender = new ReceiptSender(accountsManager, messageSender, receiptSenderExecutor);
     final TurnTokenGenerator turnTokenGenerator = new TurnTokenGenerator(dynamicConfigurationManager,
         config.getTurnConfiguration().secret().value());

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

@@ -8,15 +8,10 @@ import static com.codahale.metrics.MetricRegistry.name;
 import static org.whispersystems.textsecuregcm.entities.MessageProtos.Envelope;
 
 import com.google.common.annotations.VisibleForTesting;
-import io.micrometer.core.instrument.Counter;
 import io.micrometer.core.instrument.Metrics;
-import org.whispersystems.textsecuregcm.identity.IdentityType;
-import org.whispersystems.textsecuregcm.metrics.MetricsUtil;
 import org.whispersystems.textsecuregcm.storage.Account;
 import org.whispersystems.textsecuregcm.storage.Device;
 import org.whispersystems.textsecuregcm.storage.MessagesManager;
-import org.whispersystems.textsecuregcm.util.Util;
-import java.util.concurrent.CompletableFuture;
 
 /**
  * A MessageSender sends Signal messages to destination devices. Messages may be "normal" user-to-user messages,
@@ -27,13 +22,10 @@ import java.util.concurrent.CompletableFuture;
  * for "online" delivery only and will not be delivered (and clients will not be notified) if the destination device
  * isn't actively connected to a Signal server.
  *
- * @see ClientPresenceManager
- * @see org.whispersystems.textsecuregcm.storage.MessageAvailabilityListener
  * @see ReceiptSender
  */
 public class MessageSender {
 
-  private final PubSubClientEventManager pubSubClientEventManager;
   private final MessagesManager messagesManager;
   private final PushNotificationManager pushNotificationManager;
 
@@ -45,52 +37,31 @@ public class MessageSender {
   private static final String STORY_TAG_NAME = "story";
   private static final String SEALED_SENDER_TAG_NAME = "sealedSender";
 
-  private static final Counter CLIENT_PRESENCE_ERROR =
+  public MessageSender(final MessagesManager messagesManager, final PushNotificationManager pushNotificationManager) {
-      Metrics.counter(MetricsUtil.name(MessageSender.class, "clientPresenceError"));
-
-  public MessageSender(final PubSubClientEventManager pubSubClientEventManager,
-      final MessagesManager messagesManager,
-      final PushNotificationManager pushNotificationManager) {
-
-    this.pubSubClientEventManager = pubSubClientEventManager;
     this.messagesManager = messagesManager;
     this.pushNotificationManager = pushNotificationManager;
   }
 
-  public CompletableFuture<Void> sendMessage(final Account account, final Device device, final Envelope message, final boolean online) {
+  public void sendMessage(final Account account, final Device device, final Envelope message, final boolean online) {
-    messagesManager.insert(account.getUuid(),
+    final boolean destinationPresent = messagesManager.insert(account.getUuid(),
         device.getId(),
         online ? message.toBuilder().setEphemeral(true).build() : message);
 
-    return pubSubClientEventManager.handleNewMessageAvailable(account.getIdentifier(IdentityType.ACI), device.getId())
+    if (!destinationPresent && !online) {
-        .exceptionally(throwable -> {
-          // It's unlikely that the message insert (synchronous) would succeed and sending a "new message available"
-          // event would fail since both things happen in the same cluster, but just in case, we should "fail open" and
-          // act as if the client wasn't present if this happens. This is a conservative measure that biases toward
-          // sending more push notifications, though again, it shouldn't happen often.
-          CLIENT_PRESENCE_ERROR.increment();
-          return false;
-        })
-        .thenApply(clientPresent -> {
-          if (!clientPresent && !online) {
       try {
         pushNotificationManager.sendNewMessageNotification(account, device.getId(), message.getUrgent());
       } catch (final NotPushRegisteredException ignored) {
       }
     }
 
-          return clientPresent;
+    Metrics.counter(SEND_COUNTER_NAME,
-        })
-        .whenComplete((clientPresent, throwable) -> Metrics.counter(SEND_COUNTER_NAME,
             CHANNEL_TAG_NAME, getDeliveryChannelName(device),
             EPHEMERAL_TAG_NAME, String.valueOf(online),
-                CLIENT_ONLINE_TAG_NAME, String.valueOf(clientPresent),
+            CLIENT_ONLINE_TAG_NAME, String.valueOf(destinationPresent),
             URGENT_TAG_NAME, String.valueOf(message.getUrgent()),
             STORY_TAG_NAME, String.valueOf(message.getStory()),
             SEALED_SENDER_TAG_NAME, String.valueOf(!message.hasSourceServiceId()))
-            .increment())
+        .increment();
-        .thenRun(Util.NOOP)
-        .toCompletableFuture();
   }
 
   @VisibleForTesting

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

@@ -68,11 +68,6 @@ public class PubSubClientEventManager extends RedisClusterPubSubAdapter<byte[],
 
   private final Map<AccountAndDeviceIdentifier, ClientEventListener> listenersByAccountAndDeviceIdentifier;
 
-  private static final byte[] NEW_MESSAGE_EVENT_BYTES = ClientEvent.newBuilder()
-      .setNewMessageAvailable(NewMessageAvailableEvent.getDefaultInstance())
-      .build()
-      .toByteArray();
-
   private static final byte[] DISCONNECT_REQUESTED_EVENT_BYTES = ClientEvent.newBuilder()
       .setDisconnectRequested(DisconnectRequested.getDefaultInstance())
       .build()
@@ -229,26 +224,6 @@ public class PubSubClientEventManager extends RedisClusterPubSubAdapter<byte[],
     });
   }
 
-  /**
-   * Publishes an event notifying a specific device that a new message is available for retrieval. This method indicates
-   * whether the target device is "present" (i.e. has an active listener). Callers may choose to take follow-up action
-   * (like sending a push notification) if the target device is not present.
-   *
-   * @param accountIdentifier the account identifier of the receiving device
-   * @param deviceId the ID of the receiving device within the target account
-   *
-   * @return a future that yields {@code true} if the target device had an active listener or {@code false} otherwise
-   */
-  public CompletionStage<Boolean> handleNewMessageAvailable(final UUID accountIdentifier, final byte deviceId) {
-    if (pubSubConnection == null) {
-      throw new IllegalStateException("Presence manager not started");
-    }
-
-    return pubSubConnection.withPubSubConnection(connection ->
-            connection.async().spublish(getClientEventChannel(accountIdentifier, deviceId), NEW_MESSAGE_EVENT_BYTES))
-        .thenApply(listeners -> listeners > 0);
-  }
-
   /**
    * Publishes an event notifying a specific device that messages have been persisted from short-term to long-term
    * storage.

service/src/main/java/org/whispersystems/textsecuregcm/storage/MessagesCache.java

@@ -211,13 +211,13 @@ public class MessagesCache {
     this.removeRecipientViewFromMrmDataScript = removeRecipientViewFromMrmDataScript;
   }
 
-  public void insert(final UUID messageGuid,
+  public boolean insert(final UUID messageGuid,
       final UUID destinationAccountIdentifier,
       final byte destinationDeviceId,
       final MessageProtos.Envelope message) {
 
     final MessageProtos.Envelope messageWithGuid = message.toBuilder().setServerGuid(messageGuid.toString()).build();
-    insertTimer.record(() -> insertScript.execute(destinationAccountIdentifier, destinationDeviceId, messageWithGuid));
+    return insertTimer.record(() -> insertScript.execute(destinationAccountIdentifier, destinationDeviceId, messageWithGuid));
   }
 
   public byte[] insertSharedMultiRecipientMessagePayload(

service/src/main/java/org/whispersystems/textsecuregcm/storage/MessagesManager.java

@@ -59,14 +59,16 @@ public class MessagesManager {
     this.messageDeletionExecutor = messageDeletionExecutor;
   }
 
-  public void insert(UUID destinationUuid, byte destinationDevice, Envelope message) {
+  public boolean insert(UUID destinationUuid, byte destinationDevice, Envelope message) {
     final UUID messageGuid = UUID.randomUUID();
 
-    messagesCache.insert(messageGuid, destinationUuid, destinationDevice, message);
+    final boolean destinationPresent = messagesCache.insert(messageGuid, destinationUuid, destinationDevice, message);
 
     if (message.hasSourceServiceId() && !destinationUuid.toString().equals(message.getSourceServiceId())) {
       reportMessageManager.store(message.getSourceServiceId(), messageGuid);
     }
+
+    return destinationPresent;
   }
 
   public CompletableFuture<Boolean> mayHavePersistedMessages(final UUID destinationUuid, final Device destinationDevice) {

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

@@ -10,6 +10,7 @@ import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyBoolean;
 import static org.mockito.ArgumentMatchers.anyByte;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
@@ -20,7 +21,6 @@ import com.google.protobuf.ByteString;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.UUID;
-import java.util.concurrent.CompletableFuture;
 import org.apache.commons.lang3.RandomStringUtils;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.params.ParameterizedTest;
@@ -35,21 +35,16 @@ import org.whispersystems.textsecuregcm.storage.MessagesManager;
 
 class MessageSenderTest {
 
-  private PubSubClientEventManager pubSubClientEventManager;
   private MessagesManager messagesManager;
   private PushNotificationManager pushNotificationManager;
   private MessageSender messageSender;
 
   @BeforeEach
   void setUp() {
-    pubSubClientEventManager = mock(PubSubClientEventManager.class);
     messagesManager = mock(MessagesManager.class);
     pushNotificationManager = mock(PushNotificationManager.class);
 
-    when(pubSubClientEventManager.handleNewMessageAvailable(any(), anyByte()))
+    messageSender = new MessageSender(messagesManager, pushNotificationManager);
-        .thenReturn(CompletableFuture.completedFuture(true));
-
-    messageSender = new MessageSender(pubSubClientEventManager, messagesManager, pushNotificationManager);
   }
 
   @CartesianTest
@@ -77,10 +72,9 @@ class MessageSenderTest {
           .when(pushNotificationManager).sendNewMessageNotification(any(), anyByte(), anyBoolean());
     }
 
-    when(pubSubClientEventManager.handleNewMessageAvailable(accountIdentifier, deviceId))
+    when(messagesManager.insert(eq(accountIdentifier), eq(deviceId), any())).thenReturn(clientPresent);
-        .thenReturn(CompletableFuture.completedFuture(clientPresent));
 
-    assertDoesNotThrow(() -> messageSender.sendMessage(account, device, message, onlineMessage).join());
+    assertDoesNotThrow(() -> messageSender.sendMessage(account, device, message, onlineMessage));
 
     final MessageProtos.Envelope expectedMessage = onlineMessage
         ? message.toBuilder().setEphemeral(true).build()

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

@@ -140,30 +140,6 @@ class PubSubClientEventManagerTest {
     assertTrue(firstListenerConnectedElsewhere.get());
   }
 
-  @ParameterizedTest
-  @ValueSource(booleans = {true, false})
-  void handleNewMessageAvailable(final boolean messageAvailableRemotely) throws InterruptedException {
-    final UUID accountIdentifier = UUID.randomUUID();
-    final byte deviceId = Device.PRIMARY_ID;
-
-    final CountDownLatch messageReceivedLatch = new CountDownLatch(1);
-
-    localPresenceManager.handleClientConnected(accountIdentifier, deviceId, new ClientEventAdapter() {
-      @Override
-      public void handleNewMessageAvailable() {
-        messageReceivedLatch.countDown();
-      }
-    }).toCompletableFuture().join();
-
-    final PubSubClientEventManager messagePresenceManager =
-        messageAvailableRemotely ? remotePresenceManager : localPresenceManager;
-
-    assertTrue(messagePresenceManager.handleNewMessageAvailable(accountIdentifier, deviceId).toCompletableFuture().join());
-
-    assertTrue(messageReceivedLatch.await(2, TimeUnit.SECONDS),
-        "Message not received within time limit");
-  }
-
   @ParameterizedTest
   @ValueSource(booleans = {true, false})
   void handleMessagesPersisted(final boolean messagesPersistedRemotely) throws InterruptedException {
@@ -188,21 +164,6 @@ class PubSubClientEventManagerTest {
         "Message persistence event not received within time limit");
   }
 
-  @Test
-  void handleClientDisconnected() {
-    final UUID accountIdentifier = UUID.randomUUID();
-    final byte deviceId = Device.PRIMARY_ID;
-
-    localPresenceManager.handleClientConnected(accountIdentifier, deviceId, new ClientEventAdapter())
-        .toCompletableFuture().join();
-
-    assertTrue(localPresenceManager.handleNewMessageAvailable(accountIdentifier, deviceId).toCompletableFuture().join());
-
-    localPresenceManager.handleClientDisconnected(accountIdentifier, deviceId).toCompletableFuture().join();
-
-    assertFalse(localPresenceManager.handleNewMessageAvailable(accountIdentifier, deviceId).toCompletableFuture().join());
-  }
-
   @Test
   void isLocallyPresent() {
     final UUID accountIdentifier = UUID.randomUUID();