Converted from the bluepy library to bleak library for bluetooth access

[B1ob]

airthings.py converted to bleak by mjmccans

[lymanepp]

Use an asyncio synchronization primitive instead of polling.

[B1ob]

I fully agree with the polling. I introduced an asyncio.Event. As I understand the Event it is exactly what we need here. Can you have another look?

[mjmccans]

While unlikely, the challenge with event.wait() is that there is no timeout value and it could block indefinitely if something happens, like a bluetooth disconnect, at the wrong time. I suggest using wait_for instead with a 1 second timeout, which I have tested and works for me:

# Wait for up to one second to see if a callblack comes in.
try:
    await asyncio.wait_for(self._event.wait(), 1)
except asyncio.TimeoutError:
    _LOGGER.warn("Timeout getting command data.")
if self._command_data is not None:
    sensor_data = command_decoders[str(characteristic.uuid)].decode_data(self._command_data)
    self._command_data = None
# Stop notification handler

You can see the full code here.

[lymanepp]

Retry if not connected?

[B1ob]

good finding. @mjmccans maybe you can also pull this into your repo

[mjmccans]

Good catch @lymanepp. I didn't catch this error because the code still worked because if it failed to connect it tossed an exception and skipped over the break. In fact, I think the same error exists in the current code and worked for the same reason, but I agree this change makes the code more correct. Great to have more eyes on the code.

[lymanepp]

Any chance this TODO can be resolved?

[mjmccans]

@lymanepp That was a note to myself, but it can probably be removed now that it has worked for others. As far as I can tell I am using the same method as before, it is just that bleak returns the values quite differently than bluepy.

[MartyTremblay]

Using a 1st gen Airthings Wave which doesn't support the Hardware Revision Attribute, I'm getting the following message. I think the "Error" wording might be a bit strong and may lead users to think that the component failed.

Also, should we change it from a _LOGGER.exception to a _LOGGER.warning ?

Otherwise, component works great in 2022.6.7 and 2022.7.4 !

This error originated from a custom integration.

Logger: custom_components.airthings_wave.airthings
Source: custom_components/airthings_wave/airthings.py:266
Integration: airthings_wave (documentation, issues)
First occurred: 21:21:41 (1 occurrences)
Last logged: 21:21:41

Error getting info
Traceback (most recent call last):
  File "/config/custom_components/airthings_wave/airthings.py", line 266, in get_info
    data = await self._dev.read_gatt_char(characteristic.uuid)
  File "/usr/local/lib/python3.9/site-packages/bleak/backends/bluezdbus/client.py", line 662, in read_gatt_char
    raise BleakError(
bleak.exc.BleakError: Characteristic with UUID 00002a27-0000-1000-8000-00805f9b34fb could not be found!

[mjmccans]

@MartyTremblay I agree with your comment about line 266, and I think the following line with "self._dev = None" should be deleted as well because we should not be giving up if one of the characteristics fails to read. There may actually be an unnecessary try block as well. Perhaps the code could be cleaned up as follows:

        for mac in self.airthing_devices:
            await self.connect(mac)
            if self._dev is not None and self._dev.is_connected:  
                if self._dev is not None and self._dev.is_connected:
                    device = AirthingsDeviceInfo(serial_nr=mac)
                    for characteristic in device_info_characteristics:
                        try:
                            data = await self._dev.read_gatt_char(characteristic.uuid)
                            setattr(device, characteristic.name, data.decode(characteristic.format))
                        except:
                            _LOGGER.warning("Error getting {}".format(characteristic.name))
                self.devices[mac] = device    
                await self.disconnect()
            else:
                _LOGGER.error("Not getting device info because failed to connect to device.")