From e0bbcdfced2c4e4cd1f5cdf3cd3e60531282c5e7 Mon Sep 17 00:00:00 2001
From: "Yuichiro Tachibana (Tsuchiya)" <t.yic.yt@gmail.com>
Date: Tue, 25 Apr 2023 16:42:41 +0200
Subject: [PATCH] Use Twilio STUN/TURN servers

---
 app_deepspeech.py | 30 ++++++++++++++++++++++++++++++
 requirements.txt  |  5 +++--
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/app_deepspeech.py b/app_deepspeech.py
index 605f9f3..2543f94 100644
--- a/app_deepspeech.py
+++ b/app_deepspeech.py
@@ -4,6 +4,7 @@
 import threading
 import time
 import urllib.request
+import os
 from collections import deque
 from pathlib import Path
 from typing import List
@@ -12,6 +13,7 @@
 import numpy as np
 import pydub
 import streamlit as st
+from twilio.rest import Client
 
 from streamlit_webrtc import WebRtcMode, webrtc_streamer
 
@@ -66,6 +68,34 @@ def download_file(url, download_to: Path, expected_size=None):
             progress_bar.empty()
 
 
+# This code is based on https://github.com/whitphx/streamlit-webrtc/blob/c1fe3c783c9e8042ce0c95d789e833233fd82e74/sample_utils/turn.py
+@st.cache_data  # type: ignore
+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.  # noqa: E501
+    We considered Open Relay Project (https://www.metered.ca/tools/openrelay/) too,
+    but it is not stable and hardly works as some people reported like https://github.com/aiortc/aiortc/issues/832#issuecomment-1482420656  # noqa: E501
+    See https://github.com/whitphx/streamlit-webrtc/issues/1213
+    """
+
+    # Ref: https://www.twilio.com/docs/stun-turn/api
+    try:
+        account_sid = os.environ["TWILIO_ACCOUNT_SID"]
+        auth_token = os.environ["TWILIO_AUTH_TOKEN"]
+    except KeyError:
+        logger.warning(
+            "Twilio credentials are not set. Fallback to a free STUN server from Google."  # noqa: E501
+        )
+        return [{"urls": ["stun:stun.l.google.com:19302"]}]
+
+    client = Client(account_sid, auth_token)
+
+    token = client.tokens.create()
+
+    return token.ice_servers
+
+
+
 def main():
     st.header("Real Time Speech-to-Text")
     st.markdown(
diff --git a/requirements.txt b/requirements.txt
index 994eaad..dbbcb4f 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,5 +2,6 @@ av==9.2.0
 deepspeech==0.9.3
 numpy==1.23.0
 pydub==0.25.1
-streamlit==1.10.0
-streamlit_webrtc==0.43.0
+streamlit==1.20.0
+streamlit_webrtc==0.45.0
+twilio~=8.1.0