Install dependencies:
uv sync
This demonstrates an increase in the backpressure of a websocket connection by sending messages faster than they can be processed.
Eventually the connection is closed with either one of these generic errors:
-
A
1006
error code on the server side (connection was closed abnormally) and the same on the client side. -
A
1011
error code (internal error). The client fails immediately after the connection is closed.
Even though the underlying TCP guarantees the delivery of the messages, that does not mean the client has a chance to process all messages received in this demo. When the connection is timed out, the client drops remaining messages in the buffer, even though they are marked as delivered.
# Start the server
uv run server.py
# Start the client
uv run client.py
Server
#...
2023-12-04 10:03:37.557 | INFO | __main__:echo:26 - Sent message #1304
2023-12-04 10:03:37.581 | INFO | __main__:echo:26 - Sent message #1305
2023-12-04 10:03:37.604 | INFO | __main__:echo:26 - Sent message #1306
2023-12-04 10:04:05.961 | ERROR | __main__:echo:32 - Connection with client closed:
2023-12-04 10:04:05.961 | ERROR | __main__:echo:33 - no close frame received or sent
Client
#...
2023-12-04 10:04:15.039 | INFO | __main__:slow_processing:16 - Received message with 9,858 chars
2023-12-04 10:04:16.041 | INFO | __main__:slow_processing:16 - Received message with 10,303 chars
2023-12-04 10:04:17.042 | INFO | __main__:slow_processing:16 - Received message with 10,370 chars
2023-12-04 10:04:18.043 | ERROR | __main__:slow_processing:21 - Connection with server closed:
2023-12-04 10:04:18.044 | ERROR | __main__:slow_processing:22 - sent 1011 (internal error) keepalive ping timeout; no close frame received