WinError 10022 - multiple workers

[marodev]

Describe the bug
The Sanic server is in most of the attempts not able to start with multiple workers. Seems like the socket is not ready to bind and windows, therefore, throws an exception. This may be different on unix systems.

Code snippet
Sanic Hello World

from sanic import Sanic
from sanic.response import json

app = Sanic()


@app.route("/")
async def test(request):
    return json({"hello": "world"})


if __name__ == "__main__":
    app.run(host="127.0.0.1", port=8000, workers=2)

Expected behavior
Sanic starts and is ready to serve with multiple workers.

Environment

• OS: Windows 10
• Sanic: 19.3.1
• Python 3.6

Additional context
[2019-04-03 10:16:32 +0200] [13992] [INFO] Goin' Fast @ http://127.0.0.1:8005

[2019-04-03 10:16:35 +0200] [11836] [ERROR] Unable to start server

Traceback (most recent call last):
File "lib\site-packages\sanic\server.py", line 745, in serve
http_server = loop.run_until_complete(server_coroutine)
File "Python36_64\Lib\asyncio\base_events.py", line 468, in run_until_complete
return future.result()
File "Python36_64\Lib\asyncio\base_events.py", line 1065, in create_server
sock.listen(backlog)

OSError: [WinError 10022] An invalid argument was supplied

[2019-04-03 10:16:35 +0200] [4444] [WARNING] Sanic tried to use loop.add_signal_handler but it is not implemented on this platform.

[2019-04-03 10:16:35 +0200] [4444] [INFO] Starting worker [4444]

[sjsadowski]

This is a dupe of #1517 - as per the note there, window support is best effort and not guaranteed. While I'm leaving that open for review, I'm closing this one as redundant.

[marodev]

@sjsadowski Fair enough if you don’t want to support Windows. However, this should at least be mentioned somewhere in the docs!

[sjsadowski]

@marodev Agreed, it should be.