Completed
Pull Request — master (#161)
by Denis
03:27
created

NodeManagementService.add_references()   A

Complexity

Conditions 2

Size

Total Lines 5

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 5
CRAP Score 2
Metric Value
cc 2
dl 0
loc 5
rs 9.4285
ccs 5
cts 5
cp 1
crap 2
1 1
from threading import RLock
2 1
import logging
3 1
from datetime import datetime
4 1
try:
5 1
    import cPickle as pickle
6 1
except:
7 1
    import pickle
8
9 1
from opcua import ua
10 1
from opcua.server.users import User
11
12
13 1
class AttributeValue(object):
14
15 1
    def __init__(self, value):
16 1
        self.value = value
17 1
        self.value_callback = None
18 1
        self.datachange_callbacks = {}
19
20 1
    def __str__(self):
21
        return "AttributeValue({})".format(self.value)
22 1
    __repr__ = __str__
23
24
25 1
class NodeData(object):
26
27 1
    def __init__(self, nodeid):
28 1
        self.nodeid = nodeid
29 1
        self.attributes = {}
30 1
        self.references = []
31 1
        self.call = None
32
33 1
    def __str__(self):
34
        return "NodeData(id:{}, attrs:{}, refs:{})".format(self.nodeid, self.attributes, self.references)
35 1
    __repr__ = __str__
36
37
38 1
class AttributeService(object):
39
40 1
    def __init__(self, aspace):
41 1
        self.logger = logging.getLogger(__name__)
42 1
        self._aspace = aspace
43
44 1
    def read(self, params):
45 1
        self.logger.debug("read %s", params)
46 1
        res = []
47 1
        for readvalue in params.NodesToRead:
48 1
            res.append(self._aspace.get_attribute_value(readvalue.NodeId, readvalue.AttributeId))
49 1
        return res
50
51 1
    def write(self, params, user=User.Admin):
52 1
        self.logger.debug("write %s as user %s", params, user)
53 1
        res = []
54 1
        for writevalue in params.NodesToWrite:
55 1
            if user != User.Admin:
56 1
                if writevalue.AttributeId != ua.AttributeIds.Value:
57 1
                    res.append(ua.StatusCode(ua.StatusCodes.BadUserAccessDenied))
58 1
                    continue
59 1
                al = self._aspace.get_attribute_value(writevalue.NodeId, ua.AttributeIds.AccessLevel)
60 1
                ual = self._aspace.get_attribute_value(writevalue.NodeId, ua.AttributeIds.UserAccessLevel)
61 1
                if not ua.test_bit(al.Value.Value, ua.AccessLevel.CurrentWrite) or not ua.test_bit(ual.Value.Value, ua.AccessLevel.CurrentWrite):
62 1
                    res.append(ua.StatusCode(ua.StatusCodes.BadUserAccessDenied))
63 1
                    continue
64 1
            res.append(self._aspace.set_attribute_value(writevalue.NodeId, writevalue.AttributeId, writevalue.Value))
65 1
        return res
66
67
68 1
class ViewService(object):
69
70 1
    def __init__(self, aspace):
71 1
        self.logger = logging.getLogger(__name__)
72 1
        self._aspace = aspace
73
74 1
    def browse(self, params):
75 1
        self.logger.debug("browse %s", params)
76 1
        res = []
77 1
        for desc in params.NodesToBrowse:
78 1
            res.append(self._browse(desc))
79 1
        return res
80
81 1
    def _browse(self, desc):
82 1
        res = ua.BrowseResult()
83 1
        if desc.NodeId not in self._aspace:
84 1
            res.StatusCode = ua.StatusCode(ua.StatusCodes.BadNodeIdInvalid)
85 1
            return res
86 1
        node = self._aspace[desc.NodeId]
87 1
        for ref in node.references:
88 1
            if not self._is_suitable_ref(desc, ref):
89 1
                continue
90 1
            res.References.append(ref)
91 1
        return res
92
93 1
    def _is_suitable_ref(self, desc, ref):
94 1
        if not self._suitable_direction(desc.BrowseDirection, ref.IsForward):
95 1
            self.logger.debug("%s is not suitable due to direction", ref)
96 1
            return False
97 1
        if not self._suitable_reftype(desc.ReferenceTypeId, ref.ReferenceTypeId, desc.IncludeSubtypes):
98 1
            self.logger.debug("%s is not suitable due to type", ref)
99 1
            return False
100 1
        if desc.NodeClassMask and ((desc.NodeClassMask & ref.NodeClass) == 0):
101 1
            self.logger.debug("%s is not suitable due to class", ref)
102 1
            return False
103 1
        self.logger.debug("%s is a suitable ref for desc %s", ref, desc)
104 1
        return True
105
106 1
    def _suitable_reftype(self, ref1, ref2, subtypes):
107
        """
108
        """
109 1
        if ref1.Identifier == ref2.Identifier:
110 1
            return True
111
        #TODO: Please check the changes here
112 1
        elif not subtypes:
113 1
            return False
114 1
        oktypes = self._get_sub_ref(ref1)
115 1
        return ref2 in oktypes
116
117 1
    def _get_sub_ref(self, ref):
118 1
        res = []
119 1
        nodedata = self._aspace[ref]
120 1
        for ref in nodedata.references:
121 1
            if ref.ReferenceTypeId.Identifier == ua.ObjectIds.HasSubtype and ref.IsForward:
122 1
                res.append(ref.NodeId)
123 1
                res += self._get_sub_ref(ref.NodeId)
124 1
        return res
125
126 1
    def _suitable_direction(self, desc, isforward):
127 1
        if desc == ua.BrowseDirection.Both:
128 1
            return True
129 1
        if desc == ua.BrowseDirection.Forward and isforward:
130 1
            return True
131 1
        if desc == ua.BrowseDirection.Inverse and not isforward:
132 1
            return True
133 1
        return False
134
135 1
    def translate_browsepaths_to_nodeids(self, browsepaths):
136 1
        self.logger.debug("translate browsepath: %s", browsepaths)
137 1
        results = []
138 1
        for path in browsepaths:
139 1
            results.append(self._translate_browsepath_to_nodeid(path))
140 1
        return results
141
142 1
    def _translate_browsepath_to_nodeid(self, path):
143 1
        self.logger.debug("looking at path: %s", path)
144 1
        res = ua.BrowsePathResult()
145 1
        if path.StartingNode not in self._aspace:
146 1
            res.StatusCode = ua.StatusCode(ua.StatusCodes.BadNodeIdInvalid)
147 1
            return res
148 1
        current = path.StartingNode
149 1
        for el in path.RelativePath.Elements:
150 1
            nodeid = self._find_element_in_node(el, current)
151 1
            if not nodeid:
152 1
                res.StatusCode = ua.StatusCode(ua.StatusCodes.BadNoMatch)
153 1
                return res
154 1
            current = nodeid
155 1
        target = ua.BrowsePathTarget()
156 1
        target.TargetId = current
157 1
        target.RemainingPathIndex = 4294967295
158 1
        res.Targets = [target]
159 1
        return res
160
161 1
    def _find_element_in_node(self, el, nodeid):
162 1
        nodedata = self._aspace[nodeid]
163 1
        for ref in nodedata.references:
164
            # FIXME: here we should check other arguments!!
165 1
            if ref.BrowseName == el.TargetName:
166 1
                return ref.NodeId
167 1
        self.logger.info("element %s was not found in node %s", el, nodeid)
168 1
        return None
169
170
171 1
class NodeManagementService(object):
172
173 1
    def __init__(self, aspace):
174 1
        self.logger = logging.getLogger(__name__)
175 1
        self._aspace = aspace
176
177 1
    def add_nodes(self, addnodeitems, user=User.Admin):
178 1
        results = []
179 1
        for item in addnodeitems:
180 1
            results.append(self._add_node(item, user))
181 1
        return results
182
183 1
    def _add_node(self, item, user):
184 1
        result = ua.AddNodesResult()
185
186
        # If Identifier of requested NodeId is null we generate a new NodeId using
187
        # the namespace of the nodeid, this is an extention of the spec to allow
188
        # to requests the server to generate a new nodeid in a specified namespace
189 1
        if item.RequestedNewNodeId.has_null_identifier():
190 1
            self.logger.debug("RequestedNewNodeId has null identifier, generating Identifier")
191 1
            nodedata = NodeData(self._aspace.generate_nodeid(item.RequestedNewNodeId.NamespaceIndex))
192
        else:
193 1
            nodedata = NodeData(item.RequestedNewNodeId)
194
195 1
        if nodedata.nodeid in self._aspace:
196 1
            self.logger.warning("AddNodesItem: node already exists")
197 1
            result.StatusCode = ua.StatusCode(ua.StatusCodes.BadNodeIdExists)
198 1
            return result
199
200 1
        if item.ParentNodeId.is_null():
201
            # self.logger.warning("add_node: creating node %s without parent", nodedata.nodeid)
202
            # We should return Error here, but the standard namespace seems to define many nodes
203
            # without parents, so ignore...
204 1
            pass
205 1
        elif item.ParentNodeId not in self._aspace:
206 1
            self.logger.warning("add_node: while adding node %s, requested parent node %s does not exists", nodedata.nodeid, item.ParentNodeId)
207 1
            result.StatusCode = ua.StatusCode(ua.StatusCodes.BadParentNodeIdInvalid)
208 1
            return result
209
210 1
        if not user == User.Admin:
211 1
            result.StatusCode = ua.StatusCode(ua.StatusCodes.BadUserAccessDenied)
212 1
            return result
213
214
        # add common attrs
215 1
        nodedata.attributes[ua.AttributeIds.NodeId] = AttributeValue(ua.DataValue(ua.Variant(nodedata.nodeid, ua.VariantType.NodeId)))
216 1
        nodedata.attributes[ua.AttributeIds.BrowseName] = AttributeValue(ua.DataValue(ua.Variant(item.BrowseName, ua.VariantType.QualifiedName)))
217 1
        nodedata.attributes[ua.AttributeIds.NodeClass] = AttributeValue(ua.DataValue(ua.Variant(item.NodeClass, ua.VariantType.Int32)))
218
        # add requested attrs
219 1
        self._add_nodeattributes(item.NodeAttributes, nodedata)
220
221
        # now add our node to db
222 1
        self._aspace[nodedata.nodeid] = nodedata
223
224 1
        if not item.ParentNodeId.is_null():
225 1
            self._add_ref_from_parent(nodedata, item)
226 1
            self._add_ref_to_parent(nodedata, item, user)
227
228
        # add type definition
229 1
        if item.TypeDefinition != ua.NodeId():
230 1
            self._add_type_definition(nodedata, item, user)
231
232 1
        result.StatusCode = ua.StatusCode()
233 1
        result.AddedNodeId = nodedata.nodeid
234
235 1
        return result
236
237 1
    def _add_ref_from_parent(self, nodedata, item):
238 1
        desc = ua.ReferenceDescription()
239 1
        desc.ReferenceTypeId = item.ReferenceTypeId
240 1
        desc.NodeId = nodedata.nodeid
241 1
        desc.NodeClass = item.NodeClass
242 1
        desc.BrowseName = item.BrowseName
243 1
        desc.DisplayName = ua.LocalizedText(item.BrowseName.Name)
244 1
        desc.TypeDefinition = item.TypeDefinition
245 1
        desc.IsForward = True
246 1
        self._aspace[item.ParentNodeId].references.append(desc)
247
248 1
    def _add_ref_to_parent(self, nodedata, item, user):
249 1
        addref = ua.AddReferencesItem()
250 1
        addref.ReferenceTypeId = item.ReferenceTypeId
251 1
        addref.SourceNodeId = nodedata.nodeid
252 1
        addref.TargetNodeId = item.ParentNodeId
253 1
        addref.TargetNodeClass = self._aspace[item.ParentNodeId].attributes[ua.AttributeIds.NodeClass].value.Value.Value
254 1
        addref.IsForward = False
255 1
        self._add_reference(addref, user)
256
257 1
    def _add_type_definition(self, nodedata, item, user):
258 1
        addref = ua.AddReferencesItem()
259 1
        addref.SourceNodeId = nodedata.nodeid
260 1
        addref.IsForward = True
261 1
        addref.ReferenceTypeId = ua.NodeId(ua.ObjectIds.HasTypeDefinition)
262 1
        addref.TargetNodeId = item.TypeDefinition
263 1
        addref.TargetNodeClass = ua.NodeClass.DataType
264 1
        self._add_reference(addref, user)
265
266 1
    def delete_nodes(self, deletenodeitems, user=User.Admin):
267 1
        results = []
268 1
        for item in deletenodeitems:
269 1
            results.append(self._delete_node(item, user))
270 1
        return results
271
272 1
    def _delete_node(self, item, user):
273 1
        if user != User.Admin:
274
            return ua.StatusCode(ua.StatusCodes.BadUserAccessDenied)
275
276 1
        if item.NodeId not in self._aspace:
277
            self.logger.warning("DeleteNodesItem: node does not exists")
278
            return ua.StatusCode(ua.StatusCodes.BadNodeIdUnknown)
279
280 1
        if item.DeleteTargetReferences:
281 1
            for elem in self._aspace.keys():
282 1
                for rdesc in self._aspace[elem].references:
283 1
                    if rdesc.NodeId == item.NodeId:
284 1
                        self._aspace[elem].references.remove(rdesc)
285
286 1
        self._delete_node_callbacks(self._aspace[item.NodeId])
287
288 1
        del(self._aspace[item.NodeId])
289
290 1
        return ua.StatusCode()
291
292 1
    def _delete_node_callbacks(self, nodedata):
293 1
        if ua.AttributeIds.Value in nodedata.attributes:
294 1
            for handle, callback in nodedata.attributes[ua.AttributeIds.Value].datachange_callbacks.items():
295
                try:
296
                    callback(handle, None, ua.StatusCode(ua.StatusCodes.BadNodeIdUnknown))
297
                    self._aspace.delete_datachange_callback(handle)
298
                except Exception as ex:
299
                    self.logger.exception("Error calling delete node callback callback %s, %s, %s", nodedata, ua.AttributeIds.Value, ex)
300
301 1
    def add_references(self, refs, user=User.Admin):
302 1
        result = []
303 1
        for ref in refs:
304 1
            result.append(self._add_reference(ref, user))
305 1
        return result
306
307 1
    def _add_reference(self, addref, user):
308 1
        if addref.SourceNodeId not in self._aspace:
309
            return ua.StatusCode(ua.StatusCodes.BadSourceNodeIdInvalid)
310 1
        if addref.TargetNodeId not in self._aspace:
311 1
            return ua.StatusCode(ua.StatusCodes.BadTargetNodeIdInvalid)
312 1
        if user != User.Admin:
313
            return ua.StatusCode(ua.StatusCodes.BadUserAccessDenied)
314 1
        rdesc = ua.ReferenceDescription()
315 1
        rdesc.ReferenceTypeId = addref.ReferenceTypeId
316 1
        rdesc.IsForward = addref.IsForward
317 1
        rdesc.NodeId = addref.TargetNodeId
318 1
        rdesc.NodeClass = addref.TargetNodeClass
319 1
        bname = self._aspace.get_attribute_value(addref.TargetNodeId, ua.AttributeIds.BrowseName).Value.Value
320 1
        if bname:
321 1
            rdesc.BrowseName = bname
322 1
        dname = self._aspace.get_attribute_value(addref.TargetNodeId, ua.AttributeIds.DisplayName).Value.Value
323 1
        if dname:
324 1
            rdesc.DisplayName = dname
325 1
        self._aspace[addref.SourceNodeId].references.append(rdesc)
326 1
        return ua.StatusCode()
327
328 1
    def delete_references(self, refs, user=User.Admin):
329
        result = []
330
        for ref in refs:
331
            result.append(self._delete_reference(ref, user))
332
        return result
333
334 1
    def _delete_reference(self, item, user):
335
        if item.SourceNodeId not in self._aspace:
336
            return ua.StatusCode(ua.StatusCodes.BadSourceNodeIdInvalid)
337
        if item.TargetNodeId not in self._aspace:
338
            return ua.StatusCode(ua.StatusCodes.BadTargetNodeIdInvalid)
339
        if user != User.Admin:
340
            return ua.StatusCode(ua.StatusCodes.BadUserAccessDenied)
341
342
        for rdesc in self._aspace[item.SourceNodeId].references:
343
            if rdesc.NodeId is item.TargetNodeId:
344
                if rdesc.RefrenceTypeId != item.RefrenceTypeId:
345
                    return ua.StatusCode(ua.StatusCodes.BadReferenceTypeIdInvalid)
346
                if rdesc.IsForward == item.IsForward or item.DeleteBidirectional:
347
                    self._aspace[item.SourceNodeId].references.remove(rdesc)
348
349
        for rdesc in self._aspace[item.TargetNodeId].references:
350
            if rdesc.NodeId is item.SourceNodeId:
351
                if rdesc.RefrenceTypeId != item.RefrenceTypeId:
352
                    return ua.StatusCode(ua.StatusCodes.BadReferenceTypeIdInvalid)
353
                if rdesc.IsForward == item.IsForward or item.DeleteBidirectional:
354
                    self._aspace[item.SourceNodeId].references.remove(rdesc)
355
356
        return ua.StatusCode()
357
358 1
    def _add_node_attr(self, item, nodedata, name, vtype=None):
359 1
        if item.SpecifiedAttributes & getattr(ua.NodeAttributesMask, name):
360 1
            dv = ua.DataValue(ua.Variant(getattr(item, name), vtype))
361 1
            dv.ServerTimestamp = datetime.utcnow()
362 1
            dv.SourceTimestamp = datetime.utcnow()
363 1
            nodedata.attributes[getattr(ua.AttributeIds, name)] = AttributeValue(dv)
364
365 1
    def _add_nodeattributes(self, item, nodedata):
366 1
        self._add_node_attr(item, nodedata, "AccessLevel", ua.VariantType.Byte)
367 1
        self._add_node_attr(item, nodedata, "ArrayDimensions", ua.VariantType.Int32)
368 1
        self._add_node_attr(item, nodedata, "BrowseName", ua.VariantType.QualifiedName)
369 1
        self._add_node_attr(item, nodedata, "ContainsNoLoops", ua.VariantType.Boolean)
370 1
        self._add_node_attr(item, nodedata, "DataType", ua.VariantType.NodeId)
371 1
        self._add_node_attr(item, nodedata, "Description", ua.VariantType.LocalizedText)
372 1
        self._add_node_attr(item, nodedata, "DisplayName", ua.VariantType.LocalizedText)
373 1
        self._add_node_attr(item, nodedata, "EventNotifier", ua.VariantType.Byte)
374 1
        self._add_node_attr(item, nodedata, "Executable", ua.VariantType.Boolean)
375 1
        self._add_node_attr(item, nodedata, "Historizing", ua.VariantType.Boolean)
376 1
        self._add_node_attr(item, nodedata, "InverseName", ua.VariantType.LocalizedText)
377 1
        self._add_node_attr(item, nodedata, "IsAbstract", ua.VariantType.Boolean)
378 1
        self._add_node_attr(item, nodedata, "MinimumSamplingInterval", ua.VariantType.Double)
379 1
        self._add_node_attr(item, nodedata, "NodeClass", ua.VariantType.UInt32)
380 1
        self._add_node_attr(item, nodedata, "NodeId", ua.VariantType.NodeId)
381 1
        self._add_node_attr(item, nodedata, "Symmetric", ua.VariantType.Boolean)
382 1
        self._add_node_attr(item, nodedata, "UserAccessLevel", ua.VariantType.Byte)
383 1
        self._add_node_attr(item, nodedata, "UserExecutable", ua.VariantType.Byte)
384 1
        self._add_node_attr(item, nodedata, "UserWriteMask", ua.VariantType.Byte)
385 1
        self._add_node_attr(item, nodedata, "ValueRank", ua.VariantType.Int32)
386 1
        self._add_node_attr(item, nodedata, "WriteMask", ua.VariantType.Byte)
387 1
        self._add_node_attr(item, nodedata, "UserWriteMask", ua.VariantType.Byte)
388 1
        self._add_node_attr(item, nodedata, "Value")
389
390
391 1
class MethodService(object):
392
393 1
    def __init__(self, aspace):
394 1
        self.logger = logging.getLogger(__name__)
395 1
        self._aspace = aspace
396
397 1
    def call(self, methods):
398 1
        results = []
399 1
        for method in methods:
400 1
            results.append(self._call(method))
401 1
        return results
402
403 1
    def _call(self, method):
404 1
        res = ua.CallMethodResult()
405 1
        if method.ObjectId not in self._aspace or method.MethodId not in self._aspace:
406 1
            res.StatusCode = ua.StatusCode(ua.StatusCodes.BadNodeIdInvalid)
407
        else:
408 1
            node = self._aspace[method.MethodId]
409 1
            if node.call is None:
410
                res.StatusCode = ua.StatusCode(ua.StatusCodes.BadNothingToDo)
411
            else:
412 1
                try:
413 1
                    res.OutputArguments = node.call(method.ObjectId, *method.InputArguments)
414 1
                    for _ in method.InputArguments:
415 1
                        res.InputArgumentResults.append(ua.StatusCode())
416 1
                except Exception:
417 1
                    self.logger.exception("Error executing method call %s, an exception was raised: ", method)
418 1
                    res.StatusCode = ua.StatusCode(ua.StatusCodes.BadUnexpectedError)
419 1
        return res
420
421
422 1
class AddressSpace(object):
423
424
    """
425
    The address space object stores all the nodes og the OPC-UA server
426
    and helper methods.
427
    The methods are threadsafe
428
    """
429
430 1
    def __init__(self):
431 1
        self.logger = logging.getLogger(__name__)
432 1
        self._nodes = {}
433 1
        self._lock = RLock()  # FIXME: should use multiple reader, one writter pattern
434 1
        self._datachange_callback_counter = 200
435 1
        self._handle_to_attribute_map = {}
436 1
        self._default_idx = 2
437 1
        self._nodeid_counter = 2000
438
439 1
    def __getitem__(self, nodeid):
440 1
        with self._lock:
441 1
            return self._nodes.__getitem__(nodeid)
442
443 1
    def __setitem__(self, nodeid, value):
444 1
        with self._lock:
445 1
            return self._nodes.__setitem__(nodeid, value)
446
447 1
    def __contains__(self, nodeid):
448 1
        with self._lock:
449 1
            return self._nodes.__contains__(nodeid)
450
451 1
    def __delitem__(self, nodeid):
452 1
        with self._lock:
453 1
            self._nodes.__delitem__(nodeid)
454
455 1
    def generate_nodeid(self, idx=0):
456 1
        if not idx:
457 1
            idx = self._default_idx
458 1
        self._nodeid_counter += 1
459 1
        return ua.NodeId(self._nodeid_counter, idx)
460
461 1
    def keys(self):
462 1
        with self._lock:
463 1
            return self._nodes.keys()
464
465 1
    def dump(self, path):
466
        """
467
        dump address space as binary to file
468
        """
469
        with open(path, 'wb') as f:
470
            pickle.dump(self._nodes, f, pickle.HIGHEST_PROTOCOL)
471
472 1
    def load(self, path):
473
        """
474
        load address space from file, overwritting everything current address space
475
        """
476
        with open(path, 'rb') as f:
477
            self._nodes = pickle.load(f)
478
479 1
    def get_attribute_value(self, nodeid, attr):
480 1
        with self._lock:
481 1
            self.logger.debug("get attr val: %s %s", nodeid, attr)
482 1
            if nodeid not in self._nodes:
483 1
                dv = ua.DataValue()
484 1
                dv.StatusCode = ua.StatusCode(ua.StatusCodes.BadNodeIdUnknown)
485 1
                return dv
486 1
            node = self._nodes[nodeid]
487 1
            if attr not in node.attributes:
488 1
                dv = ua.DataValue()
489 1
                dv.StatusCode = ua.StatusCode(ua.StatusCodes.BadAttributeIdInvalid)
490 1
                return dv
491 1
            attval = node.attributes[attr]
492 1
            if attval.value_callback:
493
                return attval.value_callback()
494 1
            return attval.value
495
496 1
    def set_attribute_value(self, nodeid, attr, value):
497 1
        with self._lock:
498 1
            self.logger.debug("set attr val: %s %s %s", nodeid, attr, value)
499 1
            if nodeid not in self._nodes:
500 1
                return ua.StatusCode(ua.StatusCodes.BadNodeIdUnknown)
501 1
            node = self._nodes[nodeid]
502 1
            if attr not in node.attributes:
503 1
                return ua.StatusCode(ua.StatusCodes.BadAttributeIdInvalid)
504 1
            if not value.SourceTimestamp:
505 1
                value.SourceTimestamp = datetime.utcnow()
506 1
            if not value.ServerTimestamp:
507 1
                value.ServerTimestamp = datetime.utcnow()
508
509 1
            attval = node.attributes[attr]
510 1
            old = attval.value
511 1
            attval.value = value
512 1
            cbs = []
513 1
            if old.Value != value.Value:  # only send call callback when a value change has happend
514 1
                cbs = list(attval.datachange_callbacks.items())
515
516 1
        for k, v in cbs:
517 1
            try:
518 1
                v(k, value)
519
            except Exception as ex:
520
                self.logger.exception("Error calling datachange callback %s, %s, %s", k, v, ex)
521
522 1
        return ua.StatusCode()
523
524 1
    def add_datachange_callback(self, nodeid, attr, callback):
525 1
        with self._lock:
526 1
            self.logger.debug("set attr callback: %s %s %s", nodeid, attr, callback)
527 1
            if nodeid not in self._nodes:
528
                return ua.StatusCode(ua.StatusCodes.BadNodeIdUnknown), 0
529 1
            node = self._nodes[nodeid]
530 1
            if attr not in node.attributes:
531 1
                return ua.StatusCode(ua.StatusCodes.BadAttributeIdInvalid), 0
532 1
            attval = node.attributes[attr]
533 1
            self._datachange_callback_counter += 1
534 1
            handle = self._datachange_callback_counter
535 1
            attval.datachange_callbacks[handle] = callback
536 1
            self._handle_to_attribute_map[handle] = (nodeid, attr)
537 1
            return ua.StatusCode(), handle
538
539 1
    def delete_datachange_callback(self, handle):
540 1
        with self._lock:
541 1
            nodeid, attr = self._handle_to_attribute_map.pop(handle)
542 1
            self._nodes[nodeid].attributes[attr].datachange_callbacks.pop(handle)
543
544 1
    def add_method_callback(self, methodid, callback):
545 1
        with self._lock:
546 1
            node = self._nodes[methodid]
547
            node.call = callback
548