Upload 3 files

sample_utils/download.py

@@ -0,0 +1,50 @@
+import urllib.request
+from pathlib import Path
+
+import streamlit as st
+
+
+# This code is based on https://github.com/streamlit/demo-self-driving/blob/230245391f2dda0cb464008195a470751c01770b/streamlit_app.py#L48  # noqa: E501
+def download_file(url, download_to: Path, expected_size=None):
+    # Don't download the file twice.
+    # (If possible, verify the download using the file length.)
+    if download_to.exists():
+        if expected_size:
+            if download_to.stat().st_size == expected_size:
+                return
+        else:
+            st.info(f"{url} is already downloaded.")
+            if not st.button("Download again?"):
+                return
+
+    download_to.parent.mkdir(parents=True, exist_ok=True)
+
+    # These are handles to two visual elements to animate.
+    weights_warning, progress_bar = None, None
+    try:
+        weights_warning = st.warning("Downloading %s..." % url)
+        progress_bar = st.progress(0)
+        with open(download_to, "wb") as output_file:
+            with urllib.request.urlopen(url) as response:
+                length = int(response.info()["Content-Length"])
+                counter = 0.0
+                MEGABYTES = 2.0 ** 20.0
+                while True:
+                    data = response.read(8192)
+                    if not data:
+                        break
+                    counter += len(data)
+                    output_file.write(data)
+
+                    # We perform animation by overwriting the elements.
+                    weights_warning.warning(
+                        "Downloading %s... (%6.2f/%6.2f MB)"
+                        % (url, counter / MEGABYTES, length / MEGABYTES)
+                    )
+                    progress_bar.progress(min(counter / length, 1.0))
+    # Finally, we remove these visual elements by calling .empty().
+    finally:
+        if weights_warning is not None:
+            weights_warning.empty()
+        if progress_bar is not None:
+            progress_bar.empty()

sample_utils/turn.py

@@ -0,0 +1,39 @@
+import logging
+import os
+
+import streamlit as st
+from twilio.base.exceptions import TwilioRestException
+from twilio.rest import Client
+
+logger = logging.getLogger(__name__)
+
+
+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)
+
+    try:
+        token = client.tokens.create()
+    except TwilioRestException as e:
+        st.warning(
+            f"Error occurred while accessing Twilio API. Fallback to a free STUN server from Google. ({e})"  # noqa: E501
+        )
+        return [{"urls": ["stun:stun.l.google.com:19302"]}]
+
+    return token.ice_servers