Migrating from Streaming v2 to Streaming v3 (Python)

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import pyaudio
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import websocket
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import json
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import threading
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import time
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from urllib.parse import urlencode
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from datetime import datetime
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# --- Configuration ---
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YOUR_API_KEY = "YOUR-API-KEY"  # Replace with your actual API key
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CONNECTION_PARAMS = {
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    "sample_rate": 16000,
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    "format_turns": True,  # Request formatted final transcripts
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}
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API_ENDPOINT_BASE_URL = "wss://streaming.assemblyai.com/v3/ws"
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API_ENDPOINT = f"{API_ENDPOINT_BASE_URL}?{urlencode(CONNECTION_PARAMS)}"
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# Audio Configuration
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FRAMES_PER_BUFFER = 800  # 50ms of audio (0.05s * 16000Hz)
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SAMPLE_RATE = CONNECTION_PARAMS["sample_rate"]
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CHANNELS = 1
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FORMAT = pyaudio.paInt16
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# Global variables for audio stream and websocket
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audio = None
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stream = None
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ws_app = None
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audio_thread = None
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stop_event = threading.Event()  # To signal the audio thread to stop
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# --- WebSocket Event Handlers ---
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def on_open(ws):
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    """Called when the WebSocket connection is established."""
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    print("WebSocket connection opened.")
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    print(f"Connected to: {API_ENDPOINT}")
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    # Start sending audio data in a separate thread
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    def stream_audio():
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        global stream
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        print("Starting audio streaming...")
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        while not stop_event.is_set():
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            try:
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                audio_data = stream.read(FRAMES_PER_BUFFER, exception_on_overflow=False)
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                # Send audio data as binary message
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                ws.send(audio_data, websocket.ABNF.OPCODE_BINARY)
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            except Exception as e:
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                print(f"Error streaming audio: {e}")
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                # If stream read fails, likely means it's closed, stop the loop
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                break
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        print("Audio streaming stopped.")
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    global audio_thread
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    audio_thread = threading.Thread(target=stream_audio)
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    audio_thread.daemon = (
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        True  # Allow main thread to exit even if this thread is running
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    )
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    audio_thread.start()
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def on_message(ws, message):
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    try:
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        data = json.loads(message)
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        msg_type = data.get('type')
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        if msg_type == "Begin":
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            session_id = data.get('id')
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            expires_at = data.get('expires_at')
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            print(f"\nSession began: ID={session_id}, ExpiresAt={datetime.fromtimestamp(expires_at)}")
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        elif msg_type == "Turn":
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            transcript = data.get('transcript', '')
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            if data.get('end_of_turn'):
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                print('\r' + ' ' * 80 + '\r', end='')
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                print(transcript)
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            else:
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                print(f"\r{transcript}", end='')
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        elif msg_type == "Termination":
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            audio_duration = data.get('audio_duration_seconds', 0)
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            session_duration = data.get('session_duration_seconds', 0)
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            print(f"\nSession Terminated: Audio Duration={audio_duration}s, Session Duration={session_duration}s")
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    except json.JSONDecodeError as e:
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        print(f"Error decoding message: {e}")
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    except Exception as e:
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        print(f"Error handling message: {e}")
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def on_error(ws, error):
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    """Called when a WebSocket error occurs."""
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    print(f"\nWebSocket Error: {error}")
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    # Attempt to signal stop on error
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    stop_event.set()
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def on_close(ws, close_status_code, close_msg):
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    """Called when the WebSocket connection is closed."""
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    print(f"\nWebSocket Disconnected: Status={close_status_code}, Msg={close_msg}")
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    # Ensure audio resources are released
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    global stream, audio
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    stop_event.set()  # Signal audio thread just in case it's still running
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    if stream:
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        if stream.is_active():
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            stream.stop_stream()
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        stream.close()
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        stream = None
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    if audio:
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        audio.terminate()
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        audio = None
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    # Try to join the audio thread to ensure clean exit
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    if audio_thread and audio_thread.is_alive():
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        audio_thread.join(timeout=1.0)
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# --- Main Execution ---
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def run():
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    global audio, stream, ws_app
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    # Initialize PyAudio
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    audio = pyaudio.PyAudio()
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    # Open microphone stream
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    try:
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        stream = audio.open(
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            input=True,
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            frames_per_buffer=FRAMES_PER_BUFFER,
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            channels=CHANNELS,
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            format=FORMAT,
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            rate=SAMPLE_RATE,
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        )
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        print("Microphone stream opened successfully.")
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        print("Speak into your microphone. Press Ctrl+C to stop.")
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    except Exception as e:
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        print(f"Error opening microphone stream: {e}")
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        if audio:
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            audio.terminate()
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        return  # Exit if microphone cannot be opened
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    # Create WebSocketApp
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    ws_app = websocket.WebSocketApp(
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        API_ENDPOINT,
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        header={"Authorization": YOUR_API_KEY},
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        on_open=on_open,
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        on_message=on_message,
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        on_error=on_error,
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        on_close=on_close,
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    )
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    # Run WebSocketApp in a separate thread to allow main thread to catch KeyboardInterrupt
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    ws_thread = threading.Thread(target=ws_app.run_forever)
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    ws_thread.daemon = True
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    ws_thread.start()
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    try:
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        # Keep main thread alive until interrupted
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        while ws_thread.is_alive():
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            time.sleep(0.1)
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    except KeyboardInterrupt:
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        print("\nCtrl+C received. Stopping...")
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        stop_event.set()  # Signal audio thread to stop
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        # Send termination message to the server
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        if ws_app and ws_app.sock and ws_app.sock.connected:
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            try:
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                terminate_message = {"type": "Terminate"}
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                print(f"Sending termination message: {json.dumps(terminate_message)}")
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                ws_app.send(json.dumps(terminate_message))
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                # Give a moment for messages to process before forceful close
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                time.sleep(5)
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            except Exception as e:
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                print(f"Error sending termination message: {e}")
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        # Close the WebSocket connection (will trigger on_close)
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        if ws_app:
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            ws_app.close()
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        # Wait for WebSocket thread to finish
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        ws_thread.join(timeout=2.0)
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    except Exception as e:
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        print(f"\nAn unexpected error occurred: {e}")
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        stop_event.set()
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        if ws_app:
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            ws_app.close()
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        ws_thread.join(timeout=2.0)
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    finally:
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        # Final cleanup (already handled in on_close, but good as a fallback)
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        if stream and stream.is_active():
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            stream.stop_stream()
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        if stream:
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            stream.close()
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        if audio:
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            audio.terminate()
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        print("Cleanup complete. Exiting.")
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if __name__ == "__main__":
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    run()

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ws = websocket.WebSocketApp(
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    f'wss://api.assemblyai.com/v2/realtime/ws?sample_rate={SAMPLE_RATE}',
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    header={'Authorization': YOUR_API_KEY},
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    on_message=on_message,
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    on_open=on_open,
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    on_error=on_error,
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    on_close=on_close
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)

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CONNECTION_PARAMS = {
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    "sample_rate": 16000,
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    "format_turns": True,  # Request formatted final transcripts
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}
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API_ENDPOINT_BASE_URL = "wss://streaming.assemblyai.com/v3/ws"
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API_ENDPOINT = f"{API_ENDPOINT_BASE_URL}?{urlencode(CONNECTION_PARAMS)}"
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ws_app = websocket.WebSocketApp(
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    API_ENDPOINT,
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    header={"Authorization": YOUR_API_KEY},
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    # ...
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)

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FRAMES_PER_BUFFER = 3200  # 200ms of audio
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SAMPLE_RATE = 16000
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CHANNELS = 1
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FORMAT = pyaudio.paInt16

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FRAMES_PER_BUFFER = 800  # 50ms of audio (0.05s * 16000Hz)
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SAMPLE_RATE = CONNECTION_PARAMS["sample_rate"]
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CHANNELS = 1
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FORMAT = pyaudio.paInt16

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def on_open(ws):
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    def stream_audio():
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        while True:
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            try:
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                audio_data = stream.read(FRAMES_PER_BUFFER, exception_on_overflow=False)
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                ws.send(audio_data, websocket.ABNF.OPCODE_BINARY)
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            except Exception as e:
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                print(f'\nError streaming audio: {e}')
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                break
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    audio_thread = Thread(target=stream_audio, daemon=True)
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    audio_thread.start()

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# Global variables for better resource management
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stop_event = threading.Event()
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audio_thread = None
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def on_open(ws):
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    def stream_audio():
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        while not stop_event.is_set():
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            try:
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                audio_data = stream.read(FRAMES_PER_BUFFER, exception_on_overflow=False)
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                ws.send(audio_data, websocket.ABNF.OPCODE_BINARY)
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            except Exception as e:
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                print(f"Error streaming audio: {e}")
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                break
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    global audio_thread
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    audio_thread = threading.Thread(target=stream_audio)
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    audio_thread.daemon = True
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    audio_thread.start()

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def on_message(ws, message):
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    try:
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        msg = json.loads(message)
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        msg_type = msg.get('message_type')
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        if msg_type == 'SessionBegins':
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            session_id = msg.get('session_id')
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            print("Session ID:", session_id)
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            return
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        text = msg.get('text', '')
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        if not text:
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            return
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        if msg_type == 'PartialTranscript':
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            print(text, end='\r')
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        elif msg_type == 'FinalTranscript':
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            print(text, end='\r\n')
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        elif msg_type == 'error':
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            print(f'\nError: {msg.get("error", "Unknown error")}')
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    except Exception as e:
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        print(f'\nError handling message: {e}')

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def on_message(ws, message):
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    try:
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        data = json.loads(message)
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        msg_type = data.get('type')
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        if msg_type == "Begin":
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            session_id = data.get('id')
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            expires_at = data.get('expires_at')
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            print(f"\nSession began: ID={session_id}, ExpiresAt={datetime.fromtimestamp(expires_at)}")
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        elif msg_type == "Turn":
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            transcript = data.get('transcript', '')
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            if data.get('end_of_turn'):
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                print('\r' + ' ' * 80 + '\r', end='')
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                print(transcript)
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            else:
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                print(f"\r{transcript}", end='')
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        elif msg_type == "Termination":
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            audio_duration = data.get('audio_duration_seconds', 0)
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            session_duration = data.get('session_duration_seconds', 0)
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            print(f"\nSession Terminated: Audio Duration={audio_duration}s, Session Duration={session_duration}s")
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    except json.JSONDecodeError as e:
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        print(f"Error decoding message: {e}")
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    except Exception as e:
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        print(f"Error handling message: {e}")

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def on_close(ws, status, msg):
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    stream.stop_stream()
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    stream.close()
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    audio.terminate()
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    print('\nDisconnected')
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# Global audio resources (potential for memory leaks)
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audio = pyaudio.PyAudio()
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stream = audio.open(...)

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def on_close(ws, close_status_code, close_msg):
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    print(f"\nWebSocket Disconnected: Status={close_status_code}, Msg={close_msg}")
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    global stream, audio
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    stop_event.set()  # Signal audio thread to stop
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    if stream:
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        if stream.is_active():
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            stream.stop_stream()
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        stream.close()
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        stream = None
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    if audio:
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        audio.terminate()
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        audio = None
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    # Ensure audio thread cleanup
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    if audio_thread and audio_thread.is_alive():
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        audio_thread.join(timeout=1.0)
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def on_error(ws, error):
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    print(f"\nWebSocket Error: {error}")
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    stop_event.set()  # Signal threads to stop on error

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try:
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    ws.run_forever()
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except Exception as e:
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    print(f'\nError: {e}')

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def run():
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    # ... initialization code ...
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    ws_thread = threading.Thread(target=ws_app.run_forever)
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    ws_thread.daemon = True
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    ws_thread.start()
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    try:
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        while ws_thread.is_alive():
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            time.sleep(0.1)
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    except KeyboardInterrupt:
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        print("\nCtrl+C received. Stopping...")
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        stop_event.set()
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        # Send termination message
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        if ws_app and ws_app.sock and ws_app.sock.connected:
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            try:
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                terminate_message = {"type": "Terminate"}
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                ws_app.send(json.dumps(terminate_message))
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                time.sleep(5)  # Allow message processing
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            except Exception as e:
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                print(f"Error sending termination message: {e}")
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        ws_app.close()
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        ws_thread.join(timeout=2.0)
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    finally:
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        # Final cleanup
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        # ... resource cleanup code ...
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        pass