WEBSOCKET_IMPLEMENTATION.md•3.46 kB
# WebSocket Real-Time Chat Implementation
## Overview
Implemented real-time streaming of chat responses and tool execution via WebSocket. This eliminates the "(Processing tool calls...)" placeholder issue and provides live feedback.
## Backend Changes
### 1. New WebSocket Handler (`app/backend/app/api/websocket.py`)
- Accepts WebSocket connections at `/ws/chat`
- Handles incoming chat messages and streams responses back
- Event types: `thinking`, `text`, `tool_call_start`, `tool_call_end`, `error`, `complete`
### 2. Chat Service Streaming (`app/backend/app/services/chat_service.py`)
- Added `process_message_stream()` async generator method
- Yields real-time events as the model processes requests:
- **thinking**: Processing started
- **text**: Model generated text chunk
- **tool_call_start**: Tool execution starting
- **tool_call_end**: Tool execution completed with result
- **complete**: Full response finished
- **error**: Error occurred
### 3. Main App Update (`app/backend/app/main.py`)
- Added WebSocket route: `@app.websocket("/ws/chat")`
- Integrates with lifespan management for service injection
## Frontend Changes
### 1. WebSocket Hook (`src/hooks/useChatWebSocket.js`)
- Custom React hook for WebSocket lifecycle management
- Methods: `connect()`, `send(data)`, `disconnect()`
- Auto-reconnection handling
- Proper protocol selection (ws/wss)
### 2. Chat Page (`src/pages/ChatPage.jsx`)
- Replaced HTTP fetch with WebSocket streaming
- Handles real-time events from server
- Streams text content as it arrives
- Updates tool call history immediately upon completion
- No more "(Processing tool calls...)" placeholders
### 3. Zustand Store (`src/store/chatStore.js`)
- Enhanced `addMessage()` to support streaming
- Concatenates streamed text chunks to last assistant message
- Flag `stream: true` marks messages as part of stream
## Message Flow
### User → Server
```javascript
{
"message": "list all pods",
"conversation_id": "uuid"
}
```
### Server → Frontend (Real-time Events)
```javascript
// 1. Thinking
{ "type": "thinking", "data": { "message": "Processing..." } }
// 2. Text streaming
{
"type": "text",
"data": {
"text": "Here are the pods...",
"conversation_id": "uuid"
}
}
// 3. Tool execution start
{
"type": "tool_call_start",
"data": {
"tool_name": "list_pods",
"arguments": { "all_namespaces": true },
"conversation_id": "uuid"
}
}
// 4. Tool execution end
{
"type": "tool_call_end",
"data": {
"tool_name": "list_pods",
"arguments": { "all_namespaces": true },
"result": "pod1, pod2, ...",
"status": "completed",
"conversation_id": "uuid"
}
}
// 5. Complete
{
"type": "complete",
"data": {
"message": "Full response text",
"tool_calls": [{ ... }],
"conversation_id": "uuid"
}
}
```
## Benefits
✅ Real-time feedback - see responses as they're generated
✅ No placeholder text - actual content displayed immediately
✅ Tool execution status visible - know when tools are running
✅ Better UX - smoother, more interactive experience
✅ Scalable - supports multiple concurrent connections
## Usage
The frontend now automatically:
1. Connects to WebSocket on page load
2. Sends messages via WebSocket instead of HTTP
3. Streams responses in real-time
4. Updates UI immediately (no waiting)
5. Disconnects on page unload
No changes needed to existing API - HTTP endpoint still available as fallback.