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################################################################################
# Load test
# e.g. test for lock contention: https://github.com/sysid/sse-starlette/issues/77
#
# to run it:
# PYTHONPATH=. uvicorn examples.issue77:app
# curl http://localhost:8000/stream | pv --line-mode --average-rate > /dev/null
################################################################################
import json
import uvicorn
from fastapi import FastAPI, Request
from sse_starlette.sse import EventSourceResponse
position = (
json.dumps(
{
"position_timestamp": "2023-09-19T11:25:35.286Z",
"x": 0,
"y": 0,
"z": 0,
"a": 0,
"b": 0,
"c": 0,
# some more fields
}
)
+ "\n"
)
positions = [position] * 500
sse_clients = 0
app = FastAPI()
@app.get("/stream")
async def message_stream(request: Request):
async def event_generator():
global sse_clients
sse_clients += 1
print(f"{sse_clients} sse clients connected", flush=True)
while True:
# If client closes connection, stop sending events
if await request.is_disconnected():
break
for p in positions:
# fixes socket.send() raised exception, but makes it very slow!!
if await request.is_disconnected():
break
yield p
return EventSourceResponse(event_generator())
if __name__ == "__main__":
uvicorn.run(app, host="0.0.0.0", port=8000, log_level="error", log_config=None) # type: ignore
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