Retrieving chat history that is stored in DynamoDB and injecting the chat history to the System prompt in Nova Sonic S2s voice bot

Hi! I think you can have a look at these Amazon Nova Sonic Samples in the repository: https://github.com/aws-samples/amazon-nova-samples/tree/main/speech-to-speech

There are examples of how to set up websockets in java and nodejs.

Good afternoon, In addition to the links provided by Anna please see if any of the following help you. Based on the information given perhaps one of these will assist.

1. Handle Chat History Separately:

// Frontend
const ws = new WebSocket('your-websocket-url');
let chatHistory = [];

ws.onopen = () => {
  // Request chat history separately
  ws.send(JSON.stringify({ type: 'GET_CHAT_HISTORY' }));
};

ws.onmessage = (event) => {
  const data = JSON.parse(event.data);
  if (data.type === 'CHAT_HISTORY') {
    chatHistory = data.history;
    // Process chat history after receiving it
    initializeChat(chatHistory);
  }
};

2. Batch Processing:

// Backend
async function sendChatHistory(connection) {
  const history = await getDynamoDBHistory();
  const batchSize = 50;
  
  // Send history in smaller chunks
  for (let i = 0; i < history.length; i += batchSize) {
    const batch = history.slice(i, i + batchSize);
    await connection.send(JSON.stringify({
      type: 'CHAT_HISTORY_CHUNK',
      chunk: batch,
      isLast: i + batchSize >= history.length
    }));
  }
}

3. Use State Management:

// Using Redux or similar state management
const chatSlice = createSlice({
  name: 'chat',
  initialState: {
    history: [],
    isLoaded: false
  },
  reducers: {
    setChatHistory: (state, action) => {
      state.history = action.payload;
      state.isLoaded = true;
    }
  }
});

// Only initialize system prompt after history is loaded
useEffect(() => {
  if (chatState.isLoaded) {
    initializeSystemPrompt(chatState.history);
  }
}, [chatState.isLoaded]);

4. Promise-based Approach:

// Create a promise to handle chat history loading
let chatHistoryPromise = null;

function initializeChat() {
  chatHistoryPromise = new Promise((resolve) => {
    ws.send(JSON.stringify({ type: 'GET_CHAT_HISTORY' }));
    
    ws.onmessage = (event) => {
      const data = JSON.parse(event.data);
      if (data.type === 'CHAT_HISTORY') {
        resolve(data.history);
      }
    };
  });
  
  return chatHistoryPromise;
}

// Usage
async function setupSystem() {
  const history = await initializeChat();
  // Now safely initialize system prompt with history
  setupSystemPrompt(history);
}

5. Queue-based Solution:

class ChatQueue {
  constructor() {
    this.queue = [];
    this.isProcessing = false;
    this.historyLoaded = false;
  }

  async processQueue() {
    if (this.isProcessing || !this.historyLoaded) return;
    
    this.isProcessing = true;
    while (this.queue.length > 0) {
      const message = this.queue.shift();
      await processMessage(message);
    }
    this.isProcessing = false;
  }

  addToQueue(message) {
    this.queue.push(message);
    this.processQueue();
  }

  setHistory(history) {
    this.historyLoaded = true;
    this.processQueue();
  }
}

Best Practices:

1. Always validate the chat history data structure before processing
2. Implement error handling for WebSocket connections
3. Add loading states to handle the delay in history retrieval
4. Consider implementing a retry mechanism for failed WebSocket connections
5. Use TypeScript interfaces to ensure data consistency

Example Implementation:

interface ChatHistory {
  messages: Message[];
  timestamp: number;
}

class ChatManager {
  private history: ChatHistory | null = null;
  private ws: WebSocket;
  private readyPromise: Promise<void>;

  constructor() {
    this.ws = new WebSocket('your-websocket-url');
    this.readyPromise = this.initialize();
  }

  private async initialize() {
    await new Promise<void>((resolve) => {
      this.ws.onopen = () => resolve();
    });
    
    this.history = await this.fetchHistory();
    return this.initializeSystemPrompt(this.history);
  }

  public async sendMessage(message: string) {
    await this.readyPromise; // Ensure initialization is complete
    // Process message with history context
  }
}

This might help resolve the injection issues and maintain a stable connection.