Firebase Realtime Database - The most convenient way to debug on Flutter

Intercept Firebase RTDB operations and see them in the Network Debugger UI.

Quick start

1. Install

flutter pub add firebase_database_debugger

2. Init (debug only)

import 'package:firebase_database/firebase_database.dart';
import 'package:firebase_database_debugger/firebase_database_debugger.dart';
import 'package:flutter/foundation.dart';

final debugger = FirebaseDatabaseDebugger(
  config: FirebaseDatabaseDebuggerConfig(
    enabled: kDebugMode,
  ),
);

void main() {
  WidgetsFlutterBinding.ensureInitialized();
  // ... Firebase.initializeApp() etc.

  runApp(MyApp());
}

3. Wrap your refs

final ref = debugger.ref(FirebaseDatabase.instance.ref('users/alice'));

await ref.set({'name': 'Alice', 'age': 30});  // logged as SET
await ref.get();                                // logged as GET
await ref.update({'age': 31});                  // logged as UPDATE
await ref.remove();                             // logged as REMOVE

That's it — open the Network Debugger app (web UI or desktop app) and you'll see every operation with payload, timing and status. For setup instructions, see the Quick Start Guide.

TIP

If the Network Debugger backend is not running, events are silently dropped — the app won't crash or slow down.

---

Listeners

ref.onValue.listen((event) {
  print(event.snapshot.value);
});
// UI shows: listen_start, then onValue for each update

Nested paths

child() returns a DebugDatabaseReference, so logging is preserved:

final messages = debugger.ref(db.ref('chats/room1/messages'));
await messages.child('msg1').set({'text': 'hello'});
await messages.child('msg2').set({'text': 'world'});

Queries

Wrap with debugger.query() for orderByChild, limitToLast, etc.:

final query = debugger.query(
  db.ref('messages').orderByChild('timestamp').limitToLast(50),
);

await query.get();                        // query_get
query.onValue.listen((event) { });        // onValue
query.onChildAdded.listen((event) { });   // onChildAdded
query.onChildChanged.listen((event) { }); // onChildChanged
query.onChildRemoved.listen((event) { }); // onChildRemoved

Session grouping

By default each unique path is a separate session. Use sessionPathDepth to group related operations:

FirebaseDatabaseDebuggerConfig(
  sessionPathDepth: 2,
)

sessionPathDepth	Behavior	Example
-1 (default)	One session per full path	/users/alice and /users/bob — two sessions
0	Single session for entire database	Everything in one session
1	Group by first segment	/users/alice and /users/bob → session /users
2	Group by two segments	/users/alice/profile and /users/alice/settings → /users/alice

UI filters

The filter button on an RTDB session opens Firebase-specific filters:

• Operation — dynamic list built from actual operations in the session (set, get, update, remove, onValue, query_get, onChildAdded, etc.)
• Status — OK / Error
• Path contains — substring match on the event path (e.g. /alice)

Cleanup

await debugger.dispose();

Flushes buffered events and closes all sessions.

Configuration reference

Parameter	Default	Description
debuggerBaseUrl	http://10.0.2.2:9092 on Android emulator, otherwise http://localhost:9092	Network Debugger backend URL
enabled	true	Set false to disable logging entirely
sessionPathDepth	-1	Session grouping (see above)
flushInterval	200ms	How often buffered events are sent
maxBatchFrames	100	Max events per batch
previewBodyThresholdBytes	16 KB	Threshold before large payloads are base64-spilled

You can override defaults with --dart-define:

• FIREBASE_DATABASE_DEBUGGER_BASE_URL (or FIREBASE_DEBUGGER_BASE_URL)
• FIREBASE_DATABASE_DEBUGGER_ENABLED (or FIREBASE_DEBUGGER_ENABLED)