add timestamp for datavalues in server. since it is not default anymore

opcua/address_space.py

 from threading import RLock
 import logging
 import pickle
+from datetime import datetime
 
 from opcua import ua
 
@@ -243,6 +244,8 @@ class NodeManagementService(object):
     def _add_node_attr(self, item, nodedata, name, vtype=None):
         if item.SpecifiedAttributes & getattr(ua.NodeAttributesMask, name):
             dv = ua.DataValue(ua.Variant(getattr(item, name), vtype))
+            dv.ServerTimestamp = datetime.now()
+            dv.SourceTimestamp = datetime.now()
             nodedata.attributes[getattr(ua.AttributeIds, name)] = AttributeValue(dv)
 
     def _add_nodeattributes(self, item, nodedata):
@@ -347,12 +350,13 @@ class AddressSpace(object):
     def get_attribute_value(self, nodeid, attr):
         with self._lock:
             #self.logger.debug("get attr val: %s %s", nodeid, attr)
-            dv = ua.DataValue()
             if not nodeid in self._nodes:
+                dv = ua.DataValue()
                 dv.StatusCode = ua.StatusCode(ua.StatusCodes.BadNodeIdUnknown)
                 return dv
             node = self._nodes[nodeid]
             if attr not in node.attributes:
+                dv = ua.DataValue()
                 dv.StatusCode = ua.StatusCode(ua.StatusCodes.BadAttributeIdInvalid)
                 return dv
             attval = node.attributes[attr]
@@ -368,6 +372,11 @@ class AddressSpace(object):
             node = self._nodes[nodeid]
             if not attr in node.attributes:
                 return ua.StatusCode(ua.StatusCodes.BadAttributeIdInvalid)
+            if not value.SourceTimestamp:
+                value.SourceTimestamp = datetime.now()
+            if not value.ServerTimestamp:
+                value.ServerTimestamp = datetime.now()
+
             attval = node.attributes[attr]
             attval.value = value
             if attval.value_callback:

opcua/uatypes.py

@@ -220,7 +220,7 @@ class Guid(object):
         return isinstance(other, Guid) and self.uuid == other.uuid
 
 
-class StatusCode(object):
+class StatusCode(FrozenClass):
 
     """
     :ivar value:
@@ -262,7 +262,7 @@ class NodeIdType(object):
     ByteString = 5
 
 
-class NodeId(object):
+class NodeId(FrozenClass):
 
     """
     NodeId Object
@@ -470,7 +470,7 @@ class StringNodeId(NodeId):
 ExpandedNodeId = NodeId
 
 
-class QualifiedName(object):
+class QualifiedName(FrozenClass):
 
     '''
     A string qualified with a namespace index.
@@ -683,7 +683,7 @@ class VariantType(Enum):
     DiagnosticInfo = 25
 
 
-class Variant(object):
+class Variant(FrozenClass):
 
     """
     Create an OPC-UA Variant object.
@@ -770,7 +770,7 @@ class Variant(object):
         return obj
 
 
-class DataValue(object):
+class DataValue(FrozenClass):
 
     '''
     A value with an associated timestamp, and quality.