StaticRoute.sendfile incorrectly uses add_writer/remove_writer

[1st1]

See python/asyncio#372 for more details.

It seems that on modern OSes, aiohttp's implementation of sendfile always hits a fast path, i.e. first call to os.sendfile succeeds. On Mac OS 10.10, though, it sometimes does not, so the code calls add_writer on the underlying transport's socket.

This is a wrong thing to do, as the status of the writer callback (and the active callback itself) is the private state of the transport. It also seems that StaticRoute.sendfile may not work at all when add_writer is used.

I suggest to duplicate the socket that get_extra_info returns before adding/removing readers/writers.

[1st1]

Alright, so in the next asyncio release, using add_reader/add_writer on a socket that transport.get_extra_info('socket') returns will be an error. I'll also fix uvloop to do that too. This issue has to be fixed asap.

[asvetlov]

Fixed by #964

[asvetlov]

Alright, so in the next asyncio release, using add_reader/add_writer on a socket that transport.get_extra_info('socket') returns will be an error.

@1st1 could you point on source code change for the fix? I miss it.

[asvetlov]

Aaah, it's not implemented still.

[lock]

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