revert and fix Variant array

asyncua/server/address_space.py

@@ -458,7 +458,7 @@ class NodeManagementService:
     def _add_node_attr(self, item, nodedata, name, vtype=None, add_timestamps=False, is_array=False):
         if item.SpecifiedAttributes & getattr(ua.NodeAttributesMask, name):
             dv = ua.DataValue(
-                ua.Variant(getattr(item, name), vtype, Dimensions=[0] if is_array else None),
+                ua.Variant(getattr(item, name), vtype, is_array=is_array),
                 SourceTimestamp=datetime.utcnow() if add_timestamps else None,
             )
             nodedata.attributes[getattr(ua.AttributeIds, name)] = AttributeValue(dv)

asyncua/ua/ua_binary.py

@@ -434,19 +434,20 @@ def variant_to_binary(var):
 
 def variant_from_binary(data):
     dimensions = None
+    array = False
     encoding = ord(data.read(1))
     int_type = encoding & 0b00111111
     vtype = ua.datatype_to_varianttype(int_type)
     if test_bit(encoding, 7):
         value = unpack_uatype_array(vtype, data)
-        dimensions = [0]
+        array = True
     else:
         value = unpack_uatype(vtype, data)
     if test_bit(encoding, 6):
         dimensions = unpack_uatype_array(ua.VariantType.Int32, data)
         if value is not None:
             value = _reshape(value, dimensions)
-    return ua.Variant(value, vtype, dimensions)
+    return ua.Variant(value, vtype, dimensions, is_array=array)
 
 
 def _reshape(flat, dims):

asyncua/ua/uatypes.py

@@ -3,7 +3,7 @@ implement ua datatypes
 """
 
 import sys
-from typing import Optional, Any, Union, Generic
+from typing import Optional, Any, Union, Generic, List
 import collections
 import logging
 from enum import Enum, IntEnum
@@ -780,22 +780,29 @@ class Variant:
     :ivar VariantType:
     :vartype VariantType: VariantType
     :ivar Dimension:
-    :vartype Dimensions: The length of each dimensions. Usually guessed from value. [0] mean 1D array without length limit
+    :vartype Dimensions: The length of each dimensions. Make the variant a Matrix
+    :ivar is_array:
+    :vartype is_array: If the variant is an array. Always True if Dimension is specificied
     """
 
+    # FIXME: typing is wrong here
     Value: Any = None
     VariantType: VariantType = None
-    Dimensions: Optional[Int32] = None
+    Dimensions: Optional[List[Int32]] = None
+    is_array: Optional[bool] = None
 
     def __post_init__(self):
+
+        if self.is_array is None:
+            if isinstance(self.Value, (list, tuple)) or self.Dimensions :
+                object.__setattr__(self, "is_array", True)
+            else:
+                object.__setattr__(self, "is_array", False)
+
         if isinstance(self.Value, Variant):
             object.__setattr__(self, "VariantType", self.Value.VariantType)
             object.__setattr__(self, "Value", self.Value.Value)
 
-        if self.Dimensions is None and isinstance(self.Value, (list, tuple)):
-            dims = get_shape(self.Value)
-            object.__setattr__(self, "Dimensions", dims)
-
         if not isinstance(self.VariantType, (VariantType, VariantTypeCustom)):
             if self.VariantType is None:
                 object.__setattr__(self, "VariantType", self._guess_type(self.Value))
@@ -820,9 +827,10 @@ class Variant:
                     f"Non array Variant of type {self.VariantType} cannot have value None"
                 )
 
-    @property
-    def is_array(self):
-        return self.Dimensions is not None
+        if self.Dimensions is None and isinstance(self.Value, (list, tuple)):
+            dims = get_shape(self.Value)
+            if len(dims) > 1:
+                object.__setattr__(self, "Dimensions", dims)
 
     def __eq__(self, other):
         if (

tests/test_unit.py

@@ -30,35 +30,44 @@ EXAMPLE_BSD_PATH = os.path.abspath(os.path.join(os.path.dirname(__file__), "exam
 
 
 def test_variant_array_none():
-    v = ua.Variant(None, VariantType=ua.VariantType.Int32, Dimensions=[0])
+    v = ua.Variant(None, VariantType=ua.VariantType.Int32, is_array=True)
     data = variant_to_binary(v)
     v2 = variant_from_binary(ua.utils.Buffer(data))
     assert v == v2
     assert v2.is_array
-    assert v2.Dimensions == [0]
+    assert v2.Dimensions is None
 
-    v = ua.Variant(None, VariantType=ua.VariantType.Null, Dimensions=[0])
+    v = ua.Variant(None, VariantType=ua.VariantType.Null, is_array=True)
     data = variant_to_binary(v)
     v2 = variant_from_binary(ua.utils.Buffer(data))
     assert v == v2
     assert v2.is_array
-    assert v2.Dimensions == [0]
+    assert v2.Dimensions is None
 
-    v = ua.Variant(None, VariantType=ua.VariantType.Null, Dimensions=None)
+    v = ua.Variant(None, VariantType=ua.VariantType.Null, Dimensions=[0, 0])
     data = variant_to_binary(v)
     v2 = variant_from_binary(ua.utils.Buffer(data))
     assert v == v2
-    assert not v2.is_array
-    assert v2.Dimensions == None
+    assert v2.is_array
+    assert v2.Dimensions == [0, 0]
 
 
 
 def test_variant_empty_list():
-    v = ua.Variant([], VariantType=ua.VariantType.Int32, Dimensions=[0])
+    v = ua.Variant([], VariantType=ua.VariantType.Int32, is_array=True)
+    data = variant_to_binary(v)
+    v2 = variant_from_binary(ua.utils.Buffer(data))
+    assert v == v2
+    assert v2.is_array
+    assert v2.Dimensions is None
+
+    v = ua.Variant([], VariantType=ua.VariantType.Int32, is_array=True, Dimensions=[0])
     data = variant_to_binary(v)
     v2 = variant_from_binary(ua.utils.Buffer(data))
     assert v == v2
     assert v2.is_array
+    assert v2.Dimensions == [0]
+
 
 
 def test_custom_structs(tmpdir):
@@ -602,6 +611,7 @@ def test_variant_array():
     v2 = variant_from_binary(ua.utils.Buffer(variant_to_binary(v)))
     assert v.Value == v2.Value
     assert v.VariantType == v2.VariantType
+    assert v2.Dimensions is None
 
     now = datetime.utcnow()
     v = ua.Variant([now])
@@ -610,12 +620,16 @@ def test_variant_array():
     v2 = variant_from_binary(ua.utils.Buffer(variant_to_binary(v)))
     assert v.Value == v2.Value
     assert v.VariantType == v2.VariantType
+    assert v2.Dimensions is None
 
 
 def test_variant_array_dim():
     v = ua.Variant([1, 2, 3, 4, 5, 6], Dimensions=[2, 3])
     assert v.Value[1] == 2
+    assert v.Dimensions == [2, 3]
+
     v2 = variant_from_binary(ua.utils.Buffer(variant_to_binary(v)))
+
     assert _reshape(v.Value, (2, 3)) == v2.Value
     assert v.VariantType == v2.VariantType
     assert v.Dimensions == v2.Dimensions