juullabs / able Goto Github PK

It seems the checkConnection() function in Retry never completes,
the line Able.verbose { "checkConnection → End" } never runs.

If I use Able without the Retry layer, everything works as expected.

It would be nice to be able to scan BLE devices in a Flow rather than having to work with ScanCallback.

Until SharedFlow is released, development is occurring on internal branch (built against internal Coroutines publications).

When merging internal back into develop, ensure the following has been performed:

• Revert internal GitHub Packages publication (restore Sonatype/Maven distribution configuration)
• Remove STOPSHIPs
• Remove usage of internal packages repository: i.e. "revert" changes in #86

There is currently no special handling when Android Gatt operations (e.g. writeCharacteristic) returns false, as such, the Messenger enters a "deadlock" state because the callback.waitForGattReady() waits indefinitely.

Instead, should be releasing the GattCallback.gattLock upon a false return from an Android Gatt operation.

The false return for Gatt operations was observed after hardware errors observed on:

Samsung Galaxy A5

• Model number: SM-A520F
• Android version: 8.0.0

05-21 18:07:07.664  2451  4426 E [email protected]_controller: Error reading data from uart
05-21 18:07:07.664  2451  4426 D [email protected]_controller: ReportSocFailure
05-21 18:07:07.664  2451  4426 D [email protected]_controller: ReportSocFailure send soc failure
05-21 18:07:07.665  4344  4427 E bt_hci  : [BTCORE] Ctlr H/w error event - code:0xf
05-21 18:07:07.665  4344  4427 E bt_btif : btif_dm_error_reporter_cback : 3
05-21 18:07:07.665  4344  4377 W bt_btif : btif_dm_generic_evt: event=33037
05-21 18:07:07.665  4344  4427 W bt_btif : bta_gattc_conn_cback() - cif=3 connected=0 conn_id=3 reason=0x0003
05-21 18:07:07.665  4344  4427 W bt_btif : bta_gattc_conn_cback() - cif=4 connected=0 conn_id=4 reason=0x0003
05-21 18:07:07.665  4344  4427 W bt_btif : bta_gattc_conn_cback() - cif=5 connected=0 conn_id=5 reason=0x0003
05-21 18:07:07.665  4344  4427 W bt_btif : bta_gattc_conn_cback() - cif=6 connected=0 conn_id=6 reason=0x0003
05-21 18:07:07.665  4344  4427 E bt_btm  : btm_acl_removed:1:
05-21 18:07:07.665  4344  4427 E bt_hci  : Ctlr H/w error event - code:Tigger SSR
05-21 18:07:07.665  4344 23797 E bt_hci_factory: make_reset :: Send HCI_RESET Command
05-21 18:07:07.666  4344  4377 W bt_btif : btif_dm_generic_evt: event=33038
05-21 18:07:07.666  4344  4377 E bt_btif : BTIF_DM_CB_ERROR_REPORTER : 3

Kable will be multiplatform and supersede Able, providing a more powerful yet simpler API.

JakeWharton/timber#353 may be a good reference, or https://github.com/Kotlin/binary-compatibility-validator.

Instead, we should favor nullable return types or sealed classes.

http://www.douevencode.com/articles/2018-09/kotlin-error-handling/ summarizes it well.

Exceptions currently (develop branch) being thrown:

core

• RemoteException
• ConnectionLostException
• OutOfOrderGattCallbackException
• GattErrorStatusException

keep-alive

• NotReadyException

throw

• GattStatusException
• RemoteException
• ConnectionLostException

Is it possible to tweak connection settings like the interval value?
I saw that normally that is done using
boolean requestConnectionPriority (int connectionPriority)
which I cannot get to work with able.
Even better would be to set the connection time intervals to specific values.
The nRF app does log
Connection parameters updated (interval: 7.5ms, latency: 0, timeout: 5000ms)
when performing such connection parameter changes.

If this is possible, can you provide any code snipped on how to do that?

With #72, the KeepAliveGatt's internal Gatt property was changed to be configured prior to invoking the onConnectAction.

This resolves potential crashes when attempting to invoke KeepAliveGatt I/O methods from within the connection handler functions, but opens up potential bugs.

If a library consumer performs some critical I/O from within the onConnected connection handler (and needs those actions to be perform before any other I/O) then allowing I/O operations on KeepAliveGatt during the onConnected function could cause hard to track down bugs. It would be preferred that the external I/O threw NotReady (as that is the expected state until onConnected handler has completed.

tl;dr Consider reverting 024fc38.

perhaps a sample code to subscribe to notifications would be handy and helpful for newbies...

i'm struggling to subscribe to onCharacteristicChanged. I have already enabled notifications on my device using the below code, however can't seem to figure out how to subscribe to notification using code.

gatt.setCharacteristicNotification(characteristicTx, true)
for (des in characteristicTx.descriptors) {
if (null != des) {
gatt.writeDescriptor(des, BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE)
}
}

https://kotlinlang.org/docs/reference/whatsnew14.html#explicit-api-mode-for-library-authors

I think this could be captured by a try-catch surrounding the subscription.consumeEach call, but there is likely a cleaner solution also.

I did not authorize any of the apps or any other programs in my phone