Fix first notification not showing (#77)

The first notification data received will only be ignored if the message
is from more than 3 seconds in the past

elasticlib/Elastic.java

@@ -1,70 +1,72 @@
-package frc.robot;
+package frc.robot.util;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
-
 import edu.wpi.first.networktables.NetworkTableInstance;
 import edu.wpi.first.networktables.PubSubOption;
 import edu.wpi.first.networktables.StringPublisher;
 import edu.wpi.first.networktables.StringTopic;
 
 public final class Elastic {
-    private static final StringTopic topic = NetworkTableInstance.getDefault()
-            .getStringTopic("/Elastic/robotnotifications");
-    private static final StringPublisher publisher = topic.publish(PubSubOption.sendAll(true));
-    private static final ObjectMapper objectMapper = new ObjectMapper();
+  private static final StringTopic topic =
+      NetworkTableInstance.getDefault().getStringTopic("/Elastic/RobotNotifications");
+  private static final StringPublisher publisher =
+      topic.publish(PubSubOption.sendAll(true), PubSubOption.keepDuplicates(true));
+  private static final ObjectMapper objectMapper = new ObjectMapper();
 
-    public static void sendAlert(ElasticNotification alert) {
-        try {
-            publisher.set(objectMapper.writeValueAsString(alert));
-        } catch (JsonProcessingException e) {
-            e.printStackTrace();
-        }
+  public static void sendAlert(ElasticNotification alert) {
+    try {
+      publisher.set(objectMapper.writeValueAsString(alert));
+    } catch (JsonProcessingException e) {
+      e.printStackTrace();
     }
+  }
+
+  public static class ElasticNotification {
+    @JsonProperty("level")
+    private NotificationLevel level;
 
-    public static class ElasticNotification {
-        @JsonProperty("level")
-        private NotificationLevel level;
-        @JsonProperty("title")
-        private String title;
-        @JsonProperty("description")
-        private String description;
+    @JsonProperty("title")
+    private String title;
 
-        public ElasticNotification(NotificationLevel level, String title, String description) {
-            this.level = level;
-            this.title = title;
-            this.description = description;
-        }
+    @JsonProperty("description")
+    private String description;
 
-        public void setLevel(NotificationLevel level) {
-            this.level = level;
-        }
+    public ElasticNotification(NotificationLevel level, String title, String description) {
+      this.level = level;
+      this.title = title;
+      this.description = description;
+    }
+
+    public void setLevel(NotificationLevel level) {
+      this.level = level;
+    }
 
-        public NotificationLevel getLevel() {
-            return level;
-        }
+    public NotificationLevel getLevel() {
+      return level;
+    }
 
-        public void setTitle(String title) {
-            this.title = title;
-        }
+    public void setTitle(String title) {
+      this.title = title;
+    }
 
-        public String getTitle() {
-            return title;
-        }
+    public String getTitle() {
+      return title;
+    }
 
-        public void setDescription(String description) {
-            this.description = description;
-        }
+    public void setDescription(String description) {
+      this.description = description;
+    }
 
-        public String getDescription() {
-            return description;
-        }
+    public String getDescription() {
+      return description;
+    }
 
-        public enum NotificationLevel {
-            INFO,
-            WARNING,
-            ERROR
-        }
+    public enum NotificationLevel {
+      INFO,
+      WARNING,
+      ERROR
     }
-}
+  }
+}

lib/services/nt4_client.dart

@@ -122,11 +122,11 @@ class NT4Subscription {
   }
 
   void updateValue(Object? value, int timestamp) {
-    currentValue = value;
-    this.timestamp = timestamp;
     for (var listener in _listeners) {
-      listener(currentValue, timestamp);
+      listener(value, timestamp);
     }
+    currentValue = value;
+    this.timestamp = timestamp;
   }
 
   Map<String, dynamic> _toSubscribeJson() {
@@ -415,7 +415,7 @@ class NT4Client {
   }
 
   void addSample(NT4Topic topic, dynamic data, [int? timestamp]) {
-    timestamp ??= _getServerTimeUS();
+    timestamp ??= getServerTimeUS();
 
     _wsSendBinary(
         serialize([topic.pubUID, timestamp, topic.getTypeId(), data]));
@@ -443,7 +443,7 @@ class NT4Client {
     return DateTime.now().microsecondsSinceEpoch;
   }
 
-  int _getServerTimeUS() {
+  int getServerTimeUS() {
     return _getClientTimeUS() + _serverTimeOffsetUS;
   }
 

lib/services/nt_connection.dart

@@ -23,6 +23,8 @@ class NTConnection {
   bool get isDSConnected => _dsConnected;
   DSInteropClient get dsClient => _dsClient;
 
+  int get serverTime => _ntClient.getServerTimeUS();
+
   @visibleForTesting
   List<NT4Subscription> get subscriptions => subscriptionUseCount.keys.toList();
 

lib/services/robot_notifications_listener.dart

@@ -18,7 +18,7 @@ class RobotNotificationsListener {
 
   void listen() {
     var notifications =
-        ntConnection.subscribeAll('/Elastic/robotnotifications', 0.2);
+        ntConnection.subscribeAll('/Elastic/RobotNotifications', 0.2);
     notifications.listen((alertData, alertTimestamp) {
       if (alertData == null) {
         return;
@@ -33,7 +33,20 @@ class RobotNotificationsListener {
     // prevent showing a notification when we connect to NT
     if (_alertFirstRun) {
       _alertFirstRun = false;
-      return;
+
+      // If the alert existed 3 or more seconds before the client connected, ignore it
+      Duration serverTime = Duration(microseconds: ntConnection.serverTime);
+      Duration alertTime = Duration(microseconds: timestamp);
+
+      // In theory if you had high enough latency and there was no existing data,
+      // this would not work as intended. However, if you find yourself with 3
+      // seconds of latency you have a much more serious issue to deal with as you
+      // cannot control your robot with that much network latency, not to mention
+      // that this code wouldn't even be executing since the RTT timestamp delay
+      // would be so high that it would automatically disconnect from NT
+      if ((serverTime - alertTime).inSeconds > 3) {
+        return;
+      }
     }
 
     Map<String, dynamic> data;
@@ -43,7 +56,9 @@ class RobotNotificationsListener {
       return;
     }
 
-    if (!data.containsKey('level')) {}
+    if (!data.containsKey('level')) {
+      return;
+    }
 
     Icon icon;
 

test/pages/dashboard_page_test.dart

@@ -1182,15 +1182,17 @@ void main() {
         'level': 'INFO'
       };
 
-      MockNTConnection connection = createMockOnlineNT4(virtualTopics: [
-        NT4Topic(
-          name: '/Elastic/RobotNotifications',
-          type: NT4TypeStr.kString,
-          properties: {},
-        )
-      ], virtualValues: {
-        '/Elastic/RobotNotifications': jsonEncode(data)
-      });
+      MockNTConnection connection = createMockOnlineNT4(
+        virtualTopics: [
+          NT4Topic(
+            name: '/Elastic/RobotNotifications',
+            type: NT4TypeStr.kString,
+            properties: {},
+          )
+        ],
+        virtualValues: {'/Elastic/RobotNotifications': jsonEncode(data)},
+        serverTime: 5000000,
+      );
       MockNT4Subscription mockSub = MockNT4Subscription();
 
       List<Function(Object?, int)> listeners = [];
@@ -1232,7 +1234,7 @@ void main() {
 
       await widgetTester.pumpAndSettle();
       connection
-          .subscribeAll('/Elastic/robotnotifications', 0.2)
+          .subscribeAll('/Elastic/RobotNotifications', 0.2)
           .updateValue(jsonEncode(data), 1);
 
       await widgetTester.pump();
@@ -1244,7 +1246,7 @@ void main() {
       expect(notificationWidget, findsNothing);
 
       connection
-          .subscribeAll('/Elastic/robotnotifications', 0.2)
+          .subscribeAll('/Elastic/RobotNotifications', 0.2)
           .updateValue(jsonEncode(data), 1);
     },
   );

test/services/robot_notifications_listener_test.dart

@@ -28,7 +28,7 @@ void main() {
     notifications.listen();
 
     // Verify that subscribeAll was called with the specific parameters
-    verify(mockConnection.subscribeAll('/Elastic/robotnotifications', 0.2))
+    verify(mockConnection.subscribeAll('/Elastic/RobotNotifications', 0.2))
         .called(1);
     verify(mockConnection.addDisconnectedListener(any)).called(1);
 
@@ -39,8 +39,8 @@ void main() {
     verifyNever(mockOnNotification.call(any, any, any));
   });
 
-  test("Robot Notifications (Initial Connection | Existing Data) ", () {
-    MockNTConnection mockConnection = createMockOnlineNT4();
+  test("Robot Notifications (Initial Connection | Old Existing Data) ", () {
+    MockNTConnection mockConnection = createMockOnlineNT4(serverTime: 5000000);
     MockNT4Subscription mockSub = MockNT4Subscription();
 
     Map<String, dynamic> data = {
@@ -84,13 +84,10 @@ void main() {
     notifications.listen();
 
     // Verify that subscribeAll was called with the specific parameters
-    verify(mockConnection.subscribeAll('/Elastic/robotnotifications', 0.2))
+    verify(mockConnection.subscribeAll('/Elastic/RobotNotifications', 0.2))
         .called(1);
     verify(mockConnection.addDisconnectedListener(any)).called(1);
 
-    // Verify that no other interactions have been made with the mockConnection
-    verifyNoMoreInteractions(mockConnection);
-
     // Verify that the onNotification callback was never called
     verifyNever(mockOnNotification(any, any, any));
 
@@ -110,5 +107,67 @@ void main() {
     mockSub.updateValue(jsonEncode(data), 3);
     reset(mockOnNotification);
     verifyNever(mockOnNotification(any, any, any));
+
+    // Try with missing data
+    data.remove('level');
+    data['title'] = null;
+    data['description'] = null;
+
+    mockSub.updateValue(jsonEncode(data), 4);
+    reset(mockOnNotification);
+    verifyNever(mockOnNotification(any, any, any));
+  });
+
+  test("Robot Notifications (Initial Connection | Newer Existing Data) ", () {
+    MockNTConnection mockConnection = createMockOnlineNT4(serverTime: 5000000);
+    MockNT4Subscription mockSub = MockNT4Subscription();
+
+    Map<String, dynamic> data = {
+      'title': 'Title1',
+      'description': 'Description1',
+      'level': 'Info'
+    };
+
+    List<Function(Object?, int)> listeners = [];
+    when(mockSub.listen(any)).thenAnswer(
+      (realInvocation) {
+        listeners.add(realInvocation.positionalArguments[0]);
+        mockSub.updateValue(jsonEncode(data), 5000000);
+      },
+    );
+
+    when(mockSub.updateValue(any, any)).thenAnswer(
+      (invoc) {
+        for (var value in listeners) {
+          value.call(
+              invoc.positionalArguments[0], invoc.positionalArguments[1]);
+        }
+      },
+    );
+
+    when(mockConnection.subscribeAll(any, any)).thenAnswer(
+      (realInvocation) {
+        mockSub.updateValue(jsonEncode(data), 0);
+        return mockSub;
+      },
+    );
+
+    // Create a mock for the onNotification callback
+    MockNotificationCallback mockOnNotification = MockNotificationCallback();
+
+    RobotNotificationsListener notifications = RobotNotificationsListener(
+      ntConnection: mockConnection,
+      onNotification: mockOnNotification.call,
+    );
+
+    notifications.listen();
+
+    // Verify that subscribeAll was called with the specific parameters
+    verify(mockConnection.subscribeAll('/Elastic/RobotNotifications', 0.2))
+        .called(1);
+    verify(mockConnection.addDisconnectedListener(any)).called(1);
+
+    // Verify that the onNotification callback was called
+    verify(mockOnNotification(any, any, any));
   });
 }

test/test_util.dart

@@ -28,6 +28,8 @@ MockNTConnection createMockOfflineNT4() {
 
   when(mockNT4Connection.isNT4Connected).thenReturn(false);
 
+  when(mockNT4Connection.serverTime).thenReturn(0);
+
   when(mockNT4Connection.connectionStatus())
       .thenAnswer((_) => Stream.value(false));
 
@@ -52,6 +54,7 @@ MockNTConnection createMockOfflineNT4() {
 MockNTConnection createMockOnlineNT4({
   List<NT4Topic>? virtualTopics,
   Map<String, dynamic>? virtualValues,
+  int serverTime = 0,
 }) {
   HttpOverrides.global = null;
 
@@ -89,6 +92,8 @@ MockNTConnection createMockOnlineNT4({
 
   when(mockNT4Connection.isNT4Connected).thenReturn(true);
 
+  when(mockNT4Connection.serverTime).thenReturn(serverTime);
+
   when(mockNT4Connection.connectionStatus())
       .thenAnswer((_) => Stream.value(true));