GattServerSessionScope.kt
/*
* Copyright 2023 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.bluetooth
import kotlinx.coroutines.CancellationException
import kotlinx.coroutines.flow.Flow
import kotlinx.coroutines.flow.StateFlow
/**
* A scope for operations as a GATT server role.
*
* A scope is created for each remote device.
*
* Collect [requests] to respond with requests from the client.
*
* @see GattServerConnectRequest#accept()
*/
interface GattServerSessionScope {
/**
* A client device connected to the server.
*/
val device: BluetoothDevice
/**
* A _hot_ [Flow] of incoming requests from the client.
*
* A request is either [GattServerRequest.ReadCharacteristic] or
* [GattServerRequest.WriteCharacteristics]
*/
val requests: Flow<GattServerRequest>
/**
* A [StateFlow] of the set of characteristics that the client has requested to be
* notified of.
*
* The set will be updated whenever the client subscribes to or unsubscribes
* a characteristic.
*
* @see [GattServerSessionScope.notify]
*/
val subscribedCharacteristics: StateFlow<Set<GattCharacteristic>>
/**
* Notifies a client of a characteristic value change.
*
* @param characteristic the updated characteristic
* @param value the new value of the characteristic
*
* @throws CancellationException if it failed to notify
* @throws IllegalArgumentException if the length of the [value] is greater than
* the maximum attribute length (512)
*/
suspend fun notify(characteristic: GattCharacteristic, value: ByteArray)
}