Empty notification support when using "AcquireNotify"

[denravonska]

We are using notifications to send Protobuf data to the clients. When populated fields are the same as the defaults then Protobuf will omit them to make the wire transfer smaller. If all fields are default then the payload is empty.

Looking here it seems like bleak treats that as EOF

        def on_data():
            try:
                data = os.read(fd, 1024)
                if not data:
                    raise RuntimeError("Unexpected EOF on notification file handle")

I'm not sure what the best cause of action is here. It truly is an EOF, but it's not an error.

[denravonska]

use_start_notify=True seems to be working with this setup.

[dlech]

FYI, we just release Bleak 3.0.2 where use_start_notify=True is the default because of other unexpected issues caused by use_start_notify=False.

This is one that we haven't seen before, but is another reason that confirms we made the right choice to change the default.

Probably nothing else to do here unless we want to mention this caveat in the docs.

[denravonska]

Agree, closing this one. Documentation is probably enough, plus this will show up when people search in the future.

[dlech]

Actually, it might be OK to not raise an error here. We would just need to test what happens during a disconnect.