utils/turn.py

import logging
import os
import streamlit as st
from twilio.base.exceptions import TwilioRestException
from twilio.rest import Client
import requests

logger = logging.getLogger(__name__)

def check_connectivity():
    try:
        response = requests.get("https://api.twilio.com")
        if response.status_code == 200:
            logger.info("Twilio API is reachable.")
        else:
            logger.warning(f"Twilio API returned status code {response.status_code}")
    except requests.RequestException as e:
        logger.error(f"Failed to reach Twilio API: {e}")

    try:
        response = requests.get("https://stun.l.google.com:19302")
        if response.status_code == 200:
            logger.info("Google STUN server is reachable.")
        else:
            logger.warning(f"Google STUN server returned status code {response.status_code}")
    except requests.RequestException as e:
        logger.error(f"Failed to reach Google STUN server: {e}")

def get_ice_servers():
    """Use Twilio's TURN server because Streamlit Community Cloud has changed
    its infrastructure and WebRTC connection cannot be established without TURN server now.
    """
    check_connectivity()

    try:
        account_sid = os.environ["TWILIO_ACCOUNT_SID"]
        auth_token = os.environ["TWILIO_AUTH_TOKEN"]
        logger.info(f"Twilio SID: {account_sid}, Auth Token: {auth_token[:4]}...")  # Log partial token for security
    except KeyError:
        logger.warning(
            "Twilio credentials are not set. Fallback to a free STUN server from Google."
        )
        return [{"urls": ["stun:stun.l.google.com:19302"]}]

    client = Client(account_sid, auth_token)

    try:
        token = client.tokens.create()
    except TwilioRestException as e:
        logger.error(f"Twilio API error: {e}")
        st.warning(
            f"Error occurred while accessing Twilio API. Fallback to a free STUN server from Google. ({e})"
        )
        return [{"urls": ["stun:stun.l.google.com:19302"]}]

    return token.ice_servers