Provides a shorthand for writing to a characteristic using a service and characteristic UUID. https://github.com/JuulLabs-OSS/able

GattExtensions.kt

package com.example.myapplication

import android.bluetooth.BluetoothGattCharacteristic
import android.bluetooth.BluetoothGattService
import com.juul.able.experimental.Gatt
import com.juul.able.experimental.WriteType
import com.juul.able.experimental.throwable.writeCharacteristicOrThrow
import java.util.UUID

class GattServiceNotFound(uuid: UUID) : Exception("GATT service $uuid not found.")
class GattCharacteristicNotFound(uuid: UUID) : Exception("GATT characteristic $uuid not found.")

fun Gatt.getServiceOrThrow(uuid: UUID) =
    getService(uuid) ?: throw GattServiceNotFound(uuid)

fun BluetoothGattService.getCharacteristicOrThrow(uuid: UUID) =
    getCharacteristic(uuid) ?: throw GattCharacteristicNotFound(uuid)

suspend fun Gatt.writeCharacteristicOrThrow(
    serviceUuid: UUID,
    characteristicUuid: UUID,
    value: ByteArray,
    writeType: WriteType = BluetoothGattCharacteristic.WRITE_TYPE_DEFAULT
) {
    val characteristic = getServiceOrThrow(serviceUuid)
        .getCharacteristicOrThrow(characteristicUuid)
    writeCharacteristicOrThrow(characteristic, value, writeType)
}