Fix crash on serialization error (#328)

Author: marcelveldt

matter_server/common/helpers/json.py

@@ -4,7 +4,9 @@
 from dataclasses import is_dataclass
 from typing import Any
 
+from chip.clusters.Attribute import ValueDecodeFailure
 from chip.clusters.Types import Nullable
+from chip.tlv import float32, uint
 import orjson
 
 from .util import dataclass_to_dict
@@ -20,10 +22,14 @@ def json_encoder_default(obj: Any) -> Any:
     """
     if getattr(obj, "do_not_serialize", None):
         return None
+    if isinstance(obj, ValueDecodeFailure):
+        return None
     if isinstance(obj, (set, tuple)):
         return list(obj)
-    if isinstance(obj, float):
+    if isinstance(obj, float32):
         return float(obj)
+    if isinstance(obj, uint):
+        return int(obj)
     if hasattr(obj, "as_dict"):
         return obj.as_dict()
     if is_dataclass(obj):

matter_server/common/helpers/util.py

@@ -1,7 +1,7 @@
 """Utils for Matter server (and client)."""
 from __future__ import annotations
 
-from base64 import b64decode, b64encode
+from base64 import b64decode
 import binascii
 from dataclasses import MISSING, asdict, fields, is_dataclass
 from datetime import datetime
@@ -22,7 +22,7 @@
 )
 
 from chip.clusters.ClusterObjects import ClusterAttributeDescriptor
-from chip.clusters.Types import Nullable, NullValue
+from chip.clusters.Types import Nullable
 from chip.tlv import float32, uint
 
 if TYPE_CHECKING:
@@ -59,44 +59,17 @@ def parse_attribute_path(attribute_path: str) -> tuple[int, int, int]:
     return (int(endpoint_id_str), int(cluster_id_str), int(attribute_id_str))
 
 
-def dataclass_to_dict(obj_in: DataclassInstance, skip_none: bool = False) -> dict:
-    """Convert dataclass instance to dict, optionally skip None values."""
-    if skip_none:
-        dict_obj = asdict(
-            obj_in, dict_factory=lambda x: {k: v for (k, v) in x if v is not None}
-        )
-    else:
-        dict_obj = asdict(obj_in)
-
-    def _convert_value(value: Any) -> Any:
-        """Do some common conversions."""
-        if isinstance(value, list):
-            return [_convert_value(x) for x in value]
-        if isinstance(value, Nullable) or value == NullValue:
-            return None
-        if isinstance(value, dict):
-            return _clean_dict(value)
-        if isinstance(value, Enum):
-            return value.value
-        if isinstance(value, bytes):
-            return b64encode(value).decode("utf-8")
-        if isinstance(value, float32):
-            return float(value)
-        if type(value) == type:
-            return f"{value.__module__}.{value.__qualname__}"
-        if isinstance(value, Exception):
-            return None
-        return value
+def dataclass_to_dict(obj_in: DataclassInstance) -> dict:
+    """Convert dataclass instance to dict."""
 
-    def _clean_dict(_dict_obj: dict) -> dict:
-        _final = {}
-        for key, value in _dict_obj.items():
-            if isinstance(key, int):
-                key = str(key)
-            _final[key] = _convert_value(value)
-        return _final
-
-    return _clean_dict(dict_obj)
+    return asdict(
+        obj_in,
+        dict_factory=lambda x: {
+            # ensure the dict key is a string
+            str(k): v
+            for (k, v) in x
+        },
+    )
 
 
 def parse_utc_timestamp(datetime_string: str) -> datetime:

matter_server/server/device_controller.py

@@ -12,6 +12,7 @@
 
 from chip.ChipDeviceCtrl import CommissionableNode
 from chip.clusters import Attribute, Objects as Clusters
+from chip.clusters.Attribute import ValueDecodeFailure
 from chip.clusters.ClusterObjects import ALL_CLUSTERS, Cluster
 from chip.exceptions import ChipStackError
 
@@ -23,6 +24,7 @@
     NodeNotResolving,
 )
 from ..common.helpers.api import api_command
+from ..common.helpers.json import json_dumps
 from ..common.helpers.util import (
     create_attribute_path,
     create_attribute_path_from_attribute,
@@ -429,6 +431,10 @@ def attribute_updated_callback(
         ) -> None:
             assert self.server.loop is not None
             new_value = transaction.GetAttribute(path)
+            # failsafe: ignore ValueDecodeErrors
+            # these are set by the SDK if parsing the value failed miserably
+            if isinstance(new_value, ValueDecodeFailure):
+                return
             node_logger.debug("Attribute updated: %s - new value: %s", path, new_value)
             attr_path = str(path.Path)
             node.attributes[attr_path] = new_value
@@ -456,7 +462,6 @@ def event_callback(
             assert self.server.loop is not None
             node_logger.debug("Received node event: %s", data)
             self.event_history.append(data)
-            # TODO: This callback does not seem to fire ever or my test devices do not have events
             self.server.loop.call_soon_threadsafe(
                 self.server.signal_event, EventType.NODE_EVENT, data
             )
@@ -627,6 +632,25 @@ def _parse_attributes_from_read_result(
                     attribute_path = create_attribute_path(
                         endpoint, cluster_cls.id, attr_cls.attribute_id
                     )
+                    # failsafe: ignore ValueDecodeErrors
+                    # these are set by the SDK if parsing the value failed miserably
+                    if isinstance(attr_value, ValueDecodeFailure):
+                        continue
+                    # failsafe: make sure the attribute is serializable
+                    # there is a chance we receive malformed data from the sdk
+                    # due to all magic parsing to/from TLV.
+                    # skip an attribute in that case to prevent serialization issues
+                    # of the whole node.
+                    try:
+                        json_dumps(attr_value)
+                    except TypeError as err:
+                        LOGGER.warning(
+                            "Unserializable data found - "
+                            "skip attribute %s - error details: %s",
+                            attribute_path,
+                            err,
+                        )
+                        continue
                     result[attribute_path] = attr_value
         return result