BAB 47. CHAT ARCHITECTURE

Tujuan

Chat digunakan untuk koordinasi sebelum, saat, dan setelah sesi belajar antara siswa dan tutor, serta memungkinkan guru bergabung untuk memberikan bimbingan tambahan.

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Stack Teknologi

Komponen	Teknologi
Backend WebSocket	Laravel Reverb
Frontend Stream	Flutter + web_socket_channel
Message Storage	MySQL
Broadcast Driver	Reverb

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Arsitektur Chat

flowchart LR
    FA["📱 Flutter\n(Siswa)"] -->|"WebSocket"| RV["⚡ Laravel Reverb"]
    FB["📱 Flutter\n(Tutor)"] -->|"WebSocket"| RV
    FC["📱 Flutter\n(Guru)"]] -->|"WebSocket"| RV
    RV <-->|"Private Channel\nbooking.{id}"| LV["🟥 Laravel\nBroadcast"]
    LV --> DB[("💾 MySQL")]

    FA -->|"REST POST /messages"| API["🌐 Laravel API"]
    API --> DB
    DB -->|"MessageSent Event"| LV

    style RV fill:#dc2626,color:#fff
    style LV fill:#b45309,color:#fff

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Tipe Chat Room

Tipe	Deskripsi	Lifetime
Booking Chat	Chat antara siswa dan tutor selama proses booking	Hingga sesi selesai
Meeting Chat	Chat selama sesi berlangsung, bisa diikuti guru	Selama on_going
Group Chat	Jika ada lebih dari 1 tutor (kelompok belajar)	Hingga sesi selesai

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Model Data Chat

chat_rooms
├── id
├── booking_id       FK → bookings
├── type             enum: booking, meeting, group
└── created_at

chat_messages
├── id
├── room_id          FK → chat_rooms
├── sender_id        FK → users
├── type             enum: text, image, file, reply
├── content          text
├── attachment_path  varchar (nullable)
├── reply_to_id      FK → chat_messages (nullable)
├── is_read          boolean
└── sent_at          timestamp

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Fitur Chat

Fitur	Implementasi
Realtime	Laravel Reverb + WebSocket
Typing Indicator	Broadcast typing event
Read Receipt	Update is_read via API
Reply Message	reply_to_id kolom relasi
Image Upload	Laravel Storage + presigned URL
PDF Attachment	Laravel Storage, max 5MB
Timestamp	Disimpan di sent_at

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Implementasi Flutter

// features/chat/data/datasource/chat_realtime_datasource.dart

class ChatRealtimeDatasource {
  late final IOWebSocketChannel _channel;

  void connect(int roomId, String token) {
    _channel = IOWebSocketChannel.connect(
      Uri.parse('wss://api.temubelajar.id/app/key'),
    );

    // Subscribe to private channel
    _channel.sink.add(jsonEncode({
      'event': 'pusher:subscribe',
      'data': {'channel': 'private-room.$roomId', 'auth': token},
    }));
  }

  Stream<ChatMessage> get messages => _channel.stream
      .map((data) => ChatMessage.fromJson(jsonDecode(data)));

  void sendTyping(int roomId) {
    _channel.sink.add(jsonEncode({
      'event': 'client-typing',
      'channel': 'private-room.$roomId',
    }));
  }

  void dispose() => _channel.sink.close();
}

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Retensi Data

Tipe	Kebijakan
Booking Chat	Diarsipkan 30 hari setelah sesi selesai
Meeting Chat	Dipertahankan sebagai dokumentasi sesi
Attachment	Dihapus setelah 90 hari