resolve_gatt not implemented for bluezero.GATT.Descriptor

[JanuszSamborski]

There is call for self.resolve_gatt() inside bluezero.GATT.Descriptor's constructor, however it's not implemented.

[JanuszSamborski]

Actually, on the same note, resolve_gatt() is not called inside bluezero.GATT.Characteristic's constructor. Behavior should be probably unified.

[JanuszSamborski]

I also found that (at least for my device) the first call to resolve_gatt() can fail, and second one succeeds, so it might be viable to call get_methods at least twice with some backoff, but this would need further testing.

[ukBaz]

Hmm? That does look like it is all a bit of a mess.

I suspect that the resolve_gatt in the Service and Descriptor init's are never called because they are protected by that if statement. The services is never going to be resolved when you create the Service or Descriptor class instance.

https://github.com/ukBaz/python-bluezero/blob/6f46b6cb7102831c1427f12e65b727fc6b54774a/bluezero/GATT.py#L306-L307

I suspect the way it is done in the Central is the correct way: https://github.com/ukBaz/python-bluezero/blob/e6b4e96342de6c66571a6660d711c018f8c6b470/bluezero/central.py#L92-L94

There being no resolve_gatt for the descriptor is an oversight. Although there are only about 16 descriptors assigned by the Bluetooth SIG with fairly niche behavior so I would curious to know which one you are using.