AttributeError 'transport' with WebSocketResponse.can_prepare

[achimnol]

Long story short

Using WebSocketResponse.can_prepare() method in aiohttp 2.0.0 raises AttributeError, regardless of whether to use uvloop or the vanilla asyncio loop.
If I skip a pre-cautious call to can_prepare(), everything works fine.

Expected behaviour

It should continue without AttributeError.

Actual behaviour

With uvloop 0.8:

  File "/Users/joongi/Projects/Lablup/sorna-manager/sorna/gateway/kernel.py", line 502, in stream_pty
    if not ws.can_prepare(request):
  File "/Users/joongi/Projects/Lablup/sorna-manager/venv/lib/python3.6/site-packages/aiohttp/web_ws.py", line 1
40, in can_prepare
    self._protocols)
  File "/Users/joongi/Projects/Lablup/sorna-manager/venv/lib/python3.6/site-packages/aiohttp/http_websocket.py"
, line 570, in do_handshake
    WebSocketWriter(stream, limit=write_buffer_size),
  File "/Users/joongi/Projects/Lablup/sorna-manager/venv/lib/python3.6/site-packages/aiohttp/http_websocket.py"
, line 416, in __init__
    self.writer = stream.transport
AttributeError: 'uvloop.loop.TCPTransport' object has no attribute 'transport'

With vanilla asyncio:

  File "/Users/joongi/Projects/Lablup/sorna-manager/sorna/gateway/kernel.py", line 502, in stream_pty
    if not ws.can_prepare(request):
  File "/Users/joongi/Projects/Lablup/sorna-manager/venv/lib/python3.6/site-packages/aiohttp/web_ws.py", line 1
40, in can_prepare
    self._protocols)
  File "/Users/joongi/Projects/Lablup/sorna-manager/venv/lib/python3.6/site-packages/aiohttp/http_websocket.py"
, line 570, in do_handshake
    WebSocketWriter(stream, limit=write_buffer_size),
  File "/Users/joongi/Projects/Lablup/sorna-manager/venv/lib/python3.6/site-packages/aiohttp/http_websocket.py"
, line 416, in __init__
    self.writer = stream.transport
AttributeError: '_SelectorSocketTransport' object has no attribute 'transport'

Steps to reproduce

Just make a simple WebSocket server and explicitly call can_prepare() like below:

async def my_ws_handler(request):
    ws = web.WebSocketResponse()
    if not ws.can_prepare(request):  # commenting out this if-clause makes it working
        raise web.HTTPUpgradeRequired
    await ws.prepare(request)
    ...

Your environment

Python 3.6.0, aiohttp 2.0.0, uvloop 0.8.0 on macOS Sierra 10.2.1.

[fafhrd91]

thanks for reporting.

will release 2.0.1 today

[lock]

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