BLE Client Text Sensor
The ble_client component is a text sensor platform that can
query BLE devices for specific values of service characteristics.
For more information on BLE services and characteristics, see BLE Client.
esp32_ble_tracker:
ble_client:
  - mac_address: XX:XX:XX:XX:XX:XX
    id: itag_black
text_sensor:
  - platform: ble_client
    ble_client_id: itag_black
    name: "Sensor Location"
    service_uuid: '180d'
    characteristic_uuid: '2a38'Configuration variables
ble_client_id (Required, ID): ID of the associated BLE client.
service_uuid (Required, UUID): UUID of the service on the device.
characteristic_uuid (Required, UUID): UUID of the service’s characteristic to query.
descriptor_uuid (Optional, UUID): UUID of the characteristic’s descriptor to query.
notify (Optional, boolean): Instruct the server to send notifications for this characteristic. Defaults to
false.update_interval (Optional, Time): The interval to poll the device. Defaults to
60s.All other options from Text Sensor.
Automations:
- on_notify (Optional, Automation): An automation to
perform when a notify message is received from the device. See 
on_notify. 
BLE Sensor Automation
on_notify
This automation is triggered when the device/server sends a notify message for
a characteristic. The config variable notify must be true or this will have
no effect.
A variable x of type std::string is passed to the automation for use in lambdas.