add two part message parsing

aioacaia/acaiascale.py

@@ -15,11 +15,13 @@
 
 from .const import (
     DEFAULT_CHAR_ID,
+    HEADER1,
+    HEADER2,
     HEARTBEAT_INTERVAL,
     NOTIFY_CHAR_ID,
     OLD_STYLE_CHAR_ID,
 )
-from .exceptions import AcaiaDeviceNotFound, AcaiaError
+from .exceptions import AcaiaDeviceNotFound, AcaiaError, AcaiaMessageTooShort
 from .const import UnitMass
 from .decode import Message, Settings, decode
 from .helpers import encode, encode_id, encode_notification_request, derive_model_name
@@ -88,6 +90,8 @@ def __init__(
         self._queue: asyncio.Queue = asyncio.Queue()
         self._add_to_queue_lock = asyncio.Lock()
 
+        self._last_short_msg: bytearray | None = None
+
         self._msg_types["auth"] = encode_id(is_pyxis_style=is_new_style_scale)
 
         if not is_new_style_scale:
@@ -222,7 +226,7 @@ async def connect(
             address_or_ble_device=self.address_or_ble_device,
             disconnected_callback=self.device_disconnected_handler,
         )
-        self._client.get_services()
+
         try:
             await self._client.connect()
         except BleakError as ex:
@@ -389,7 +393,21 @@ async def on_bluetooth_data_received(
         data: bytearray,
     ) -> None:
         """Receive data from scale."""
-        msg = decode(data)[0]
+
+        # For some scales the header is sent and then in next message the content
+        if (
+            self._last_short_msg is not None
+            and self._last_short_msg[0] == HEADER1
+            and self._last_short_msg[1] == HEADER2
+        ):
+            data = self._last_short_msg + data
+            self._last_short_msg = None
+
+        try:
+            msg = decode(data)[0]
+        except AcaiaMessageTooShort as ex:
+            self._last_short_msg = ex.bytes_recvd
+            return
 
         if isinstance(msg, Settings):
             self._device_state = AcaiaDeviceState(

aioacaia/decode.py

@@ -5,6 +5,7 @@
 from bleak import BleakGATTCharacteristic
 
 from .const import HEADER1, HEADER2
+from .exceptions import AcaiaMessageTooShort
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -161,7 +162,7 @@ def decode(byte_msg: bytearray):
 
     if msg_start < 0 or len(byte_msg) - msg_start < 6:
         _LOGGER.debug("Message too short %s", byte_msg)
-        return (None, byte_msg)
+        raise AcaiaMessageTooShort(byte_msg)
 
     msg_end = msg_start + byte_msg[msg_start + 3] + 5
 

aioacaia/exceptions.py

@@ -17,3 +17,13 @@ class AcaiaError(BleakError):
 
 class AcaiaUnknownDevice(Exception):
     """Exception for unknown devices."""
+
+
+class AcaiaMessageTooShort(Exception):
+    """Exception for messages that are too short."""
+
+    def __init__(
+        self, bytes_recvd: bytearray, message: str = "Message too short"
+    ) -> None:
+        super().__init__(message)
+        self.bytes_recvd = bytes_recvd

run.py

@@ -2,9 +2,27 @@
 
 from aioacaia import AcaiaScale
 from aioacaia.decode import notification_handler
+from aioacaia.decode import decode, Message
 
 
 async def main():
+    scale = AcaiaScale("aa:bb:cc:dd:ee:ff")
+    await scale.on_bluetooth_data_received(None, bytearray(b"\xef\xdd\x0c"))
+    res = await scale.on_bluetooth_data_received(
+        None, bytearray(b"\x0c\x05\xdf\x06\x00\x00\x01\x00\x07\x00\x00\x02\xf3\r")
+    )
+    decode(
+        bytearray(b"\xef\xdd\x0c\x0c\x05\xdf\x06\x00\x00\x01\x00\x07\x00\x00\x02\xf3\r")
+    )
+    # Message(5, bytearray(b"\xdf\x06\x00\x00\x01\x00\x07\x00\x00\x02\xf3\r"))
+    # Message(5, b"\xa1\x10\x00\x00\x01\x01\x07\x00\x00\x02\xb5\x18")
+    # Message(5, bytearray(b"]\x07\x00\x00\x01\x00\x07\x00\x00\x02q\x0e"))
+    # 0 = 12
+    # 1 = 5
+    Message(5, b"\x00\x00\x00\x00\x01\x00\x07\x00\x00\x02\x14\x07")
+    decode(bytearray(b"\x0c\x05\x00\x00\x00\x00\x01\x00\x07\x00\x00\x02\x14\x07"))
+    exit(0)
+
     with open("mac.txt", "r") as f:
         mac = f.read().strip()
 

setup.py

@@ -5,7 +5,7 @@
 
 setuptools.setup(
     name="aioacaia",
-    version="0.1.4",
+    version="0.1.5b1",
     description="An async implementation of PyAcaia",
     long_description=readme,
     long_description_content_type="text/markdown",