Hi Kenny, On Sun, Jan 24, 2021 at 12:45 AM Kenny Bian <kennybian@xxxxxxxxx> wrote: > > Hello, > > We implemented a GATT server on Linux in Python. The code is based on > the code sample(https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/test/example-gatt-server). > The BlueZ version is 5.48. But we found a problem. The cached data in > /var/lib/bluetooth caused the mobile app to crash if some > characteristics are changed. After some research, we found "Under BLE > standard 'Generic Attribute'(0x1801), there is a Characteristic > 'Service Changed' (0x2A05) with 'indicate' property", see > https://github.com/espressif/esp-idf/issues/1777. > > The questions we have: > How to enable the "Service Changed Indication"(0x2A05) in the > bluetooth? Is there any code example in Python? If you are registering the services with Bluetoothd then it should generate the service change automatically: https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/src/gatt-database.c#n1185 When a new service is registered it is indicated here: https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/src/gatt-database.c#n1452 -- Luiz Augusto von Dentz
