From ad9730529def74157b69a02d371d97bf6681aedf Mon Sep 17 00:00:00 2001
From: bitkeeper <bitkeeper@users.noreply.github.com>
Date: Tue, 16 May 2017 14:10:57 +0200
Subject: [PATCH] [xmlimporter] support use of extension dictionaries

---
 opcua/common/xmlimporter.py | 19 ++++++++++++++++---
 opcua/ua/uatypes.py         | 10 +++++++++-
 2 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/opcua/common/xmlimporter.py b/opcua/common/xmlimporter.py
index d9572e929..49cd8b0fd 100644
--- a/opcua/common/xmlimporter.py
+++ b/opcua/common/xmlimporter.py
@@ -53,7 +53,7 @@ def import_xml(self, xmlpath):
 
         self.namespaces = self._map_namespaces(self.parser.get_used_namespaces())
         self.aliases = self._map_aliases(self.parser.get_aliases())
-        
+
         dnodes = self.parser.get_node_datas()
         dnodes = self.make_objects(dnodes)
         nodes_parsed = self._sort_nodes_by_parentid(dnodes)
@@ -98,7 +98,7 @@ def _add_references(self, refs):
             return self.server.iserver.isession.add_references(refs)
         else:
             return self.server.uaclient.add_references(refs)
-    
+
     def make_objects(self, node_datas):
         new_nodes = []
         for ndata in node_datas:
@@ -206,8 +206,21 @@ def add_variable(self, obj):
         res[0].StatusCode.check()
         return res[0].AddedNodeId
 
+    def _get_ext_class(self, name):
+        if hasattr(ua, name):
+            return  getattr(ua, name)
+        elif name in self.aliases.keys():
+            nodeid = self.aliases[name]
+            class_type = ua.uatypes.get_extensionobject_class_type(nodeid)
+            if class_type:
+                return class_type
+            else:
+                raise Exception("Error no extension class registered ", name, nodeid)
+        else:
+            raise Exception("Error no alias found for extension class", name)
+
     def _make_ext_obj(self, obj):
-        ext = getattr(ua, obj.objname)()
+        ext = self._get_ext_class(obj.objname)()
         for name, val in obj.body:
             if isinstance(val, str):
                 raise Exception("Error val should a dict", name, val)
diff --git a/opcua/ua/uatypes.py b/opcua/ua/uatypes.py
index 645fac1ac..fe003f655 100644
--- a/opcua/ua/uatypes.py
+++ b/opcua/ua/uatypes.py
@@ -283,7 +283,7 @@ def __init__(self, identifier=None, namespaceidx=0, nodeidtype=None):
                 raise UaError("NodeId: Could not guess type of NodeId, set NodeIdType")
 
     def _key(self):
-        if self.NodeIdType in (NodeIdType.TwoByte, NodeIdType.FourByte, NodeIdType.Numeric): 
+        if self.NodeIdType in (NodeIdType.TwoByte, NodeIdType.FourByte, NodeIdType.Numeric):
             # twobyte, fourbyte and numeric may represent the same node
             return (NodeIdType.Numeric, self.NamespaceIndex, self.Identifier)
         return (self.NodeIdType, self.NamespaceIndex, self.Identifier)
@@ -1129,6 +1129,14 @@ def register_extension_object(name, nodeid, class_type):
     extension_object_classes[nodeid] = class_type
     extension_object_ids[name] = nodeid
 
+def get_extensionobject_class_type(typeid):
+    """
+    Returns the registered class type for typid of an extension object
+    """
+    if typeid in extension_object_classes:
+        return extension_object_classes[typeid]
+    else:
+        return None
 
 def extensionobject_from_binary(data):
     """