Custom device with Mode capability: Message signature mismatched. It's likely your AppSecret is incorrect.

[joseportillodev]

Hi developers,

I'm facing an issue using a custom device with a "Mode" capability and Python SinricPro SDK 3.1.1.

Whenever I try to update the given mode from SinricPro Dashboard or the iOS App, this message appears on the dashboard:

Message signature mismatched. It's likely your AppSecret is incorrect.

The issue does not happen when updating the on/off state or the temperature setpoint, only happens for Mode or Range capabilities.

The device has these capabilities:

The Mode capability has these settings:

The callback function:

async def on_mode_state(value: Any) -> bool:
	global last_combustion_power
	log = logging.getLogger()

	log.info('device_id: {} set mode: {}'.format(THERMOSTAT_ID, value))
	if value in ("P1", "P2", "P3", "P4", "P5", "P6", "AUTO"):
		last_combustion_power = value
		return True
	return False

Hacking the callback function to also expose the instance id (as in ESP8266/ESP32 SDK):

async def on_mode_state(value: Any) -> bool:
	global last_combustion_power
	log = logging.getLogger()

	# Inspect instance id from callstack
	instance = None
	try:
		stack = inspect.stack()
		frame = next(s for s in stack if s.function == 'handle_request').frame
		instance = frame.f_locals.get('request').instance
	except:
		pass  # couldn't find handle_request

	if instance:
		log.info('device_id: {} set mode: {} = {}'.format(THERMOSTAT_ID, instance, value))
	else:
		log.info('device_id: {} set mode: {}'.format(THERMOSTAT_ID, value))
	if value in ("P1", "P2", "P3", "P4", "P5", "P6", "AUTO"):
		last_combustion_power = value
		return True
	return False

Python app logs:

dic 22 22:33:38 raspi-lasian pysinricpro[3997]: 2025-12-22 22:33:38,298 - websockets.client - DEBUG - > platform: Python
dic 22 22:33:38 raspi-lasian pysinricpro[3997]: 2025-12-22 22:33:38,301 - websockets.client - DEBUG - > SDKVersion: 3.1.1
dic 22 22:33:38 raspi-lasian pysinricpro[3997]: 2025-12-22 22:33:38,304 - websockets.client - DEBUG - > User-Agent: Python/3.11 websockets/15.0.1
...
dic 22 22:34:18 raspi-lasian pysinricpro[3997]: 2025-12-22 22:34:18,862 - websockets.client - DEBUG - > PING 4a ac 0b 86 [binary, 4 bytes]
dic 22 22:34:18 raspi-lasian pysinricpro[3997]: 2025-12-22 22:34:18,870 - websockets.client - DEBUG - % sent keepalive ping
dic 22 22:34:18 raspi-lasian pysinricpro[3997]: 2025-12-22 22:34:18,965 - websockets.client - DEBUG - < PONG 4a ac 0b 86 [binary, 4 bytes]
dic 22 22:34:18 raspi-lasian pysinricpro[3997]: 2025-12-22 22:34:18,970 - websockets.client - DEBUG - % received keepalive pong
dic 22 22:34:37 raspi-lasian pysinricpro[3997]: 2025-12-22 22:34:37,078 - websockets.client - DEBUG - < TEXT '{"header":{"payloadVersion":2,"signatureVersion...g8XxJrIz5APjZ24nXlM="}}' [373 bytes]
dic 22 22:34:37 raspi-lasian pysinricpro[3997]: 2025-12-22 22:34:37,121 - root - INFO - device_id: 6949********a61c set mode: CombustionPower = AUTO
dic 22 22:34:37 raspi-lasian pysinricpro[3997]: 2025-12-22 22:34:37,128 - websockets.client - DEBUG - > TEXT '{"header": {"payloadVersion": 2, "signatureVers...Q5i8IglrNjEq9kCK/xw="}}' [416 bytes]
dic 22 22:34:38 raspi-lasian pysinricpro[3997]: 2025-12-22 22:34:38,867 - websockets.client - DEBUG - > PING 15 e7 15 f0 [binary, 4 bytes]
dic 22 22:34:38 raspi-lasian pysinricpro[3997]: 2025-12-22 22:34:38,874 - websockets.client - DEBUG - % sent keepalive ping
dic 22 22:34:38 raspi-lasian pysinricpro[3997]: 2025-12-22 22:34:38,962 - websockets.client - DEBUG - < PONG 15 e7 15 f0 [binary, 4 bytes]

SinricPro portal log:

---

Also (probably unrelated), when updating the given mode from the Python application side, an unexpected state of "garage door was closed" is displayed on the dashboard:

Code:

if combustionPower != last_combustion_power:
	log.info('device_id: {} set combustion power: {}'.format(THERMOSTAT_ID, combustionPower))  # "AUTO"
	success = await device.send_mode_event(combustionPower)
	if success:
		log.debug("[Event] OK send_event")
		last_combustion_power = combustionPower
	else:
		log.warning("[Event] Failed to send_event")

Log:

2025-12-22 22:59:01,787 - root - INFO - device_id: 6949********a61c set combustion power: AUTO
2025-12-22 22:59:01,787 - root - DEBUG - [Event] OK send_event

Display:

[kakopappa]

Hi @joseportillodev

Thanks a lot for reporting these issues. I noticed few things are missing in the latest sdk and raised a PR to resolve them: https://github.com/sinricpro/python-sdk/pull/77/files

1. InstanceId - added for setMode and setRangeValue commands.
2. Signature calculation issue has been fixed.
3. Missing examples added.
4. Custom Device Type example updated to showcase mode, range callbacks with instance id

If you are using SDK version 3.1.x please note that this new SDK 5.0.0 includes a new breaking feature to remove restoreDeviceStates in 4.0.x. We are planning to introduce this flag in the server side to control it instead of hardcoding it in the client.

UI issue needs a separate fix, It will be released with other new features (settings) around 30th Dec.

[joseportillodev]

Oh, I thought 3.x was the latest one. I now see there are also 4-dev and 5-dev, with these related changes for SDK 5:

• feat: setMode, setRangeValue - instance id support added.
• fix: Signature mismatch issue fixed.

For the moment, I'm using the latest stable version at the "pip" PyPi.org repo, which is 3.1.1. I think I can live with the "Signature mismatch" until I migrate to version 5 in the future.

In my code, I've temporarily subclassed SinricProCustomDevice with custom versions of the send_mode_event, send_range_value_event and send_event functions in order to allow an additional parameter for the instance id:

class SinricProCustomDevice2(SinricProCustomDevice):
	async def send_mode_event(self, instance: str, mode: str, cause: str = "PHYSICAL_INTERACTION") -> bool:
		"""Send door mode event (Open/Close)."""
		if not self._mode_limiter.can_send_event():
			return False
		if not hasattr(self, "send_event"):
			return False
		device: SinricProDevice = self  # type: ignore
		success = await device.send_event(action=ACTION_SET_MODE, instance=instance, value={"mode": mode}, cause=cause)
		if success:
			device._mode_limiter.event_sent()
		return success

	async def send_range_value_event(self, instance: str, range_value: int, cause: str = "PHYSICAL_INTERACTION") -> bool:
		"""Send range value event."""
		if not self._range_limiter.can_send_event():
			return False
		if not hasattr(self, "send_event"):
			return False
		device: SinricProDevice = self  # type: ignore
		success = await device.send_event(action=ACTION_SET_RANGE_VALUE, instance=instance, value={"rangeValue": range_value}, cause=cause)
		if success:
			device._range_limiter.event_sent()
		return success

	async def send_event(
			self,
			action: str,
			value: dict[str, Any],
			instance: str = "",
			cause: str = "PHYSICAL_INTERACTION",
		) -> bool:

		if not self._sinric_pro:
			SinricProLogger.error("Device not added to SinricPro instance")
			return False

		message = {
			"header": {
				"payloadVersion": 2,
				"signatureVersion": 1,
			},
			"payload": {
				"action": action,
				"cause": {"type": cause},
				"createdAt": self._sinric_pro.get_timestamp(),
				"deviceId": self._device_id,
				"type": "event",
				"instanceId": instance,
				"value": value,
			},
		}

		try:
			await self._sinric_pro.send_message(message)
			return True
		except Exception as e:
			SinricProLogger.error(f"Failed to send event: {e}")
			return False

This way my Python application sends those events now including the instance id (as does the ESP8266/ESP32 SDK) and then the values are reflected properly on the Dashboard and on the mobile App.

(the "garage door was closed" state is no longer displayed)

There's still the issue with the signature mismatch message, when trying to update a Mode or a Range from the Dashboard or mobile App.

In those cases anyway, Python receives the event properly and I can get its instance id + mode/value, so I can handle the stove as I need.

So, in the Mode/Range event handlers, I call send_mode_event/send_range_value_event as a temporary fix to update the UI with the new set mode/value (since the "return True" in the on_mode_state/on_range_value callbacks is discarded by the server due to the signature issue)

async def on_mode_state(value: Any) -> bool:
	...
	if value in ("P1", "P2", "P3", "P4", "P5", "P6", "AUTO"):
		# TODO: Handle stove power
		last_combustion_power = value

		# Hack: update back to Web/App UI
		await device.send_mode_event(instance, value)

		# Event processed ok, UI would normally display new value
		return True
	return False

Would it be possible to fix the signature mismatch issue for the 3.x branch? Maybe backport the fix from 5-dev?

[kakopappa]

Hi @joseportillodev

Just released version 5.0 to PyPI!

I’ve already tested and verified your reported issues in this release both the signature mismatch error and the instance ID problem have been resolved.

Thanks so much for your help and feedback!