FrenoCorp/analysis/fre600_websocket_foundation.md

FRE-600: WebSocket Foundation + Yjs CRDT Sync

Phase 1 Implementation Status

✅ Completed Components

1. Core Infrastructure

• tsconfig.json - TypeScript configuration with SolidJS support
• vite.config.ts - Vite build configuration with WebSocket proxy
• package.json - Dependencies and scripts

2. Yjs Document Structure (src/lib/collaboration/yjs-document.ts)

• createScreenplayDoc() - Creates Yjs document with screenplay structure
• getOrCreateSharedTypes() - Access to shared types (Text, Map)
• Metadata, characters, and scenes management

3. WebSocket Connection Manager (src/lib/collaboration/websocket-connection.ts)

• WebSocketConnection class implementing WebSocketConnectionManager interface
• Automatic reconnection with exponential backoff
• Connection status tracking (connecting, connected, disconnected, reconnecting)
• JWT authentication support

4. CRDT Document Manager (src/lib/collaboration/crdt-document.ts)

• CRDTDocument class implementing CRDTDocumentManager interface
• Document lifecycle management
• Undo/Redo stack integration
• WebSocket provider coordination

5. WebSocket Server (server/websocket/)

• server.ts - Core WebSocket server with Yjs sync protocol
  • Document state management
  • Client connection tracking
  • Message handling (sync, update)
  • JWT authentication middleware
• index.ts - Server entry point with configuration

6. SolidJS Bindings (src/lib/collaboration/solid-bindings.ts)

• useYText() - Reactive binding for Yjs Text
• useYMap() - Reactive binding for Yjs Map
• useYArray() - Reactive binding for Yjs Array
• useCollaborativeText() - Collaborative editor binding
• useCollaborativeDoc() - Full document binding

7. Collaborative Editor Component (src/components/editor/collaborative-editor.tsx)

• CollaborativeEditor component
• Real-time text synchronization
• Cursor position preservation
• Event handling for collaborative edits

8. Tests (src/lib/collaboration/crdt-document.test.ts)

• Document creation tests
• Text synchronization tests
• Concurrent operations tests
• Undo/Redo tests
• Metadata management tests
• Character and scene storage tests

📋 Usage Example

// Client-side initialization
import { CRDTDocument } from './src/lib/collaboration/crdt-document';

const docManager = new CRDTDocument();
await docManager.initialize(
  'project-123',
  'ws://localhost:8080',
  'jwt-auth-token'
);

// Access the document
const doc = await docManager.initialize(...);
const text = doc.getText('main');
text.insert(0, 'Hello, collaborative world!');

// SolidJS integration
import { useCollaborativeDoc } from './src/lib/collaboration/solid-bindings';

function Editor() {
  const { text, metadata } = useCollaborativeDoc(doc);
  
  return (
    <CollaborativeEditor
      doc={doc}
      projectId="project-123"
      userId="user-456"
    />
  );
}

🚀 Running the Server

# Install dependencies
npm install

# Start development server
npm run dev

# Start WebSocket server
npm run server:dev

# Run tests
npm test

📁 File Structure

src/
├── lib/
│   └── collaboration/
│       ├── yjs-document.ts          # Yjs document structure
│       ├── websocket-connection.ts  # WebSocket client
│       ├── crdt-document.ts         # CRDT manager
│       ├── solid-bindings.ts        # SolidJS reactive bindings
│       └── crdt-document.test.ts    # Unit tests
└── components/
    └── editor/
        └── collaborative-editor.tsx # Collaborative editor component

server/
└── websocket/
    ├── server.ts   # WebSocket server implementation
    └── index.ts    # Server entry point

🔧 Configuration

Environment Variables

# WebSocket Server
WS_PORT=8080
JWT_SECRET=your-secret-key
ENABLE_AUTH=true

# Client
VITE_WS_URL=ws://localhost:8080

✅ Deliverables Met

• Two app instances can sync text changes via WebSocket
• Basic undo/redo functionality
• Connection status indicator
• Unit tests for CRDT operations

📊 Next Steps (Phase 2)

1. Implement PresenceManager with cursor tracking
2. Set up Redis for presence state
3. Create CollaboratorList component
4. Implement remote cursor rendering
5. Add user idle detection

📝 Dependencies Status

• FRE-586 (Core editor): Needed for editor component attachment
• FRE-588 (DB schema): Needed for project metadata
• FRE-596 (Auth): Needed for JWT token generation

⚠️ Known Blockers

1. WebSocket server infrastructure deployment - Server code ready, needs deployment
2. JWT authentication setup - Requires FRE-596 auth tokens

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Status: Phase 1 foundation complete, ready for Code Review Next Phase: Presence & Visibility (Weeks 3-4)