Server API SendData not delivered to Python data_received listeners in 1.0.16 (worked in 1.0.13) #519
Description
Summary
Related Slack thread: https://livekit-users.slack.com/archives/C07FVFM5NA1/p1760636896172949
After upgrading livekit Python SDK from 1.0.13 → 1.0.16, data sent via RoomService SendData API (Server API) is not delivered to Python SDK listeners (room.on("data_received")).
Data sent by a participant via local_participant.publish_data(...) still triggers the event.
Looks like a regression since this works in Python SDK version 1.0.13.
Environment
- Python SDK: 1.0.16 (works as expected on 1.0.13)
- Python: 3.12
- Server call: RoomService SendData (Python code example below, but issue should be independent of caller)
Expected behavior
RoomService.sendData(...) delivers data to connected participants and fires room.on("data_received") in the Python SDK, same as local_participant.publish_data(...).
Actual behavior
room.on("data_received") does not fire for messages sent via RoomService.sendData(...) (tested with kind=RELIABLE with destination = None and specific Identities).
local_participant.publish_data(...) continues to fire the event as expected.
Minimal repro
Client (python-sdk):
basic_room.py example
Server API call:
import os
import requests
import base64
from livekit import api
from dotenv import load_dotenv
load_dotenv()
# ensure LIVEKIT_URL, LIVEKIT_API_KEY, and LIVEKIT_API_SECRET are set
if __name__ == "__main__":
message = "Hello world"
room_name = 'my-room'
# Generate access token with room admin permissions
token = api.AccessToken() \
.with_identity("data-sender") \
.with_grants(api.VideoGrants(
room=room_name,
room_join=True,
room_admin=True, # Required for RoomService API calls
can_publish=True, # Required to send data
can_subscribe=True # Good practice for bridge services
)) \
.to_jwt()
# Convert WebSocket URL to HTTP API URL
api_url = os.environ.get('LIVEKIT_URL').replace('wss://', 'https://').replace('ws://', 'http://')
if not api_url.endswith('/'):
api_url += '/'
# Send data message via REST API
url = f"{api_url}twirp/livekit.RoomService/SendData"
headers = {
'Authorization': f'Bearer {token}',
'Content-Type': 'application/json'
}
payload = {
'room': room_name,
'data': base64.b64encode(message.encode("utf-8")).decode("ascii"),
'kind': 'reliable', # Use reliable delivery
'destination_identities': None,
}
response = requests.post(url, json=payload, headers=headers, timeout=10)
if response.status_code == 200:
print(f"Successfully sent message to room")
else:
print(f"Failed to send message. Status: {response.status_code}, Response: {response.text}")
raise Exception(f"LiveKit API error: {response.status_code} - {response.text}")