fix(realtime): Lower heartbeat interval to 25s (#1119)

Author: grdsdev

packages/realtime_client/lib/src/constants.dart

@@ -3,6 +3,7 @@ import 'package:realtime_client/src/version.dart';
 class Constants {
   static const String vsn = '1.0.0';
   static const Duration defaultTimeout = Duration(milliseconds: 10000);
+  static const int defaultHeartbeatIntervalMs = 25000;
   static const int wsCloseNormal = 1000;
   static const Map<String, String> defaultHeaders = {
     'X-Client-Info': 'realtime-dart/$version',

packages/realtime_client/lib/src/realtime_client.dart

@@ -65,7 +65,7 @@ class RealtimeClient {
   final WebSocketTransport transport;
   final Client? httpClient;
   final _log = Logger('supabase.realtime');
-  int heartbeatIntervalMs = 30000;
+  int heartbeatIntervalMs = Constants.defaultHeartbeatIntervalMs;
   Timer? heartbeatTimer;
 
   /// reference ID of the most recently sent heartbeat.
@@ -122,7 +122,7 @@ class RealtimeClient {
     String endPoint, {
     WebSocketTransport? transport,
     this.timeout = Constants.defaultTimeout,
-    this.heartbeatIntervalMs = 30000,
+    this.heartbeatIntervalMs = Constants.defaultHeartbeatIntervalMs,
     this.logger,
     RealtimeEncode? encode,
     RealtimeDecode? decode,

packages/realtime_client/test/socket_test.dart

@@ -79,7 +79,7 @@ void main() {
       });
       expect(socket.timeout, const Duration(milliseconds: 10000));
       expect(socket.longpollerTimeout, 20000);
-      expect(socket.heartbeatIntervalMs, 30000);
+      expect(socket.heartbeatIntervalMs, Constants.defaultHeartbeatIntervalMs);
       expect(
         socket.logger is void Function(
           String? kind,