Completed
Push — master ( b08d7a...e5fff1 )
by Olivier
04:24 queued 01:04
created

ViewService._get_sub_ref()   B

Complexity

Conditions 5

Size

Total Lines 9

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 8
CRAP Score 5

Importance

Changes 1
Bugs 0 Features 0
Metric Value
cc 5
dl 0
loc 9
ccs 8
cts 8
cp 1
crap 5
rs 8.5454
c 1
b 0
f 0
1 1
from threading import RLock
2 1
import logging
3 1
from datetime import datetime
4 1
import collections
5 1
import shelve
6 1
try:
7 1
    import cPickle as pickle
8 1
except:
9 1
    import pickle
10
11 1
from opcua import ua
12 1
from opcua.server.users import User
13
14
15 1
class AttributeValue(object):
16
17 1
    def __init__(self, value):
18 1
        self.value = value
19 1
        self.value_callback = None
20 1
        self.datachange_callbacks = {}
21
22 1
    def __str__(self):
23
        return "AttributeValue({})".format(self.value)
24 1
    __repr__ = __str__
25
26
27 1
class NodeData(object):
28
29 1
    def __init__(self, nodeid):
30 1
        self.nodeid = nodeid
31 1
        self.attributes = {}
32 1
        self.references = []
33 1
        self.call = None
34
35 1
    def __str__(self):
36
        return "NodeData(id:{}, attrs:{}, refs:{})".format(self.nodeid, self.attributes, self.references)
37 1
    __repr__ = __str__
38
39
40 1
class AttributeService(object):
41
42 1
    def __init__(self, aspace):
43 1
        self.logger = logging.getLogger(__name__)
44 1
        self._aspace = aspace
45
46 1
    def read(self, params):
47 1
        self.logger.debug("read %s", params)
48 1
        res = []
49 1
        for readvalue in params.NodesToRead:
50 1
            res.append(self._aspace.get_attribute_value(readvalue.NodeId, readvalue.AttributeId))
51 1
        return res
52
53 1
    def write(self, params, user=User.Admin):
54 1
        self.logger.debug("write %s as user %s", params, user)
55 1
        res = []
56 1
        for writevalue in params.NodesToWrite:
57 1
            if user != User.Admin:
58 1
                if writevalue.AttributeId != ua.AttributeIds.Value:
59 1
                    res.append(ua.StatusCode(ua.StatusCodes.BadUserAccessDenied))
60 1
                    continue
61 1
                al = self._aspace.get_attribute_value(writevalue.NodeId, ua.AttributeIds.AccessLevel)
62 1
                ual = self._aspace.get_attribute_value(writevalue.NodeId, ua.AttributeIds.UserAccessLevel)
63 1
                if not ua.ua_binary.test_bit(al.Value.Value, ua.AccessLevel.CurrentWrite) or not ua.ua_binary.test_bit(ual.Value.Value, ua.AccessLevel.CurrentWrite):
64 1
                    res.append(ua.StatusCode(ua.StatusCodes.BadUserAccessDenied))
65 1
                    continue
66 1
            res.append(self._aspace.set_attribute_value(writevalue.NodeId, writevalue.AttributeId, writevalue.Value))
67 1
        return res
68
69
70 1
class ViewService(object):
71
72 1
    def __init__(self, aspace):
73 1
        self.logger = logging.getLogger(__name__)
74 1
        self._aspace = aspace
75
76 1
    def browse(self, params):
77 1
        self.logger.debug("browse %s", params)
78 1
        res = []
79 1
        for desc in params.NodesToBrowse:
80 1
            res.append(self._browse(desc))
81 1
        return res
82
83 1
    def _browse(self, desc):
84 1
        res = ua.BrowseResult()
85 1
        if desc.NodeId not in self._aspace:
86 1
            res.StatusCode = ua.StatusCode(ua.StatusCodes.BadNodeIdInvalid)
87 1
            return res
88 1
        node = self._aspace[desc.NodeId]
89 1
        for ref in node.references:
90 1
            if not self._is_suitable_ref(desc, ref):
91 1
                continue
92 1
            res.References.append(ref)
93 1
        return res
94
95 1
    def _is_suitable_ref(self, desc, ref):
96 1
        if not self._suitable_direction(desc.BrowseDirection, ref.IsForward):
97 1
            self.logger.debug("%s is not suitable due to direction", ref)
98 1
            return False
99 1
        if not self._suitable_reftype(desc.ReferenceTypeId, ref.ReferenceTypeId, desc.IncludeSubtypes):
100 1
            self.logger.debug("%s is not suitable due to type", ref)
101 1
            return False
102 1
        if desc.NodeClassMask and ((desc.NodeClassMask & ref.NodeClass) == 0):
103 1
            self.logger.debug("%s is not suitable due to class", ref)
104 1
            return False
105 1
        self.logger.debug("%s is a suitable ref for desc %s", ref, desc)
106 1
        return True
107
108 1
    def _suitable_reftype(self, ref1, ref2, subtypes):
109
        """
110
        """
111 1
        if not subtypes and ref2.Identifier == ua.ObjectIds.HasSubtype:
112 1
            return False
113
        if ref1.Identifier == ref2.Identifier:
114 1
            return True
115 1
        oktypes = self._get_sub_ref(ref1)
116 1
        if not subtypes and ua.NodeId(ua.ObjectIds.HasSubtype) in oktypes:
117 1
            oktypes.remove(ua.NodeId(ua.ObjectIds.HasSubtype))
118
        return ref2 in oktypes
119 1
120 1
    def _get_sub_ref(self, ref):
121 1
        res = []
122 1
        nodedata = self._aspace[ref]
123 1
        if nodedata is not None:
124 1
            for ref in nodedata.references:
125 1
                if ref.ReferenceTypeId.Identifier == ua.ObjectIds.HasSubtype and ref.IsForward:
126 1
                    res.append(ref.NodeId)
127
                    res += self._get_sub_ref(ref.NodeId)
128 1
        return res
129 1
130 1
    def _suitable_direction(self, desc, isforward):
131 1
        if desc == ua.BrowseDirection.Both:
132 1
            return True
133 1
        if desc == ua.BrowseDirection.Forward and isforward:
134 1
            return True
135 1
        if desc == ua.BrowseDirection.Inverse and not isforward:
136
            return True
137 1
        return False
138 1
139 1
    def translate_browsepaths_to_nodeids(self, browsepaths):
140 1
        self.logger.debug("translate browsepath: %s", browsepaths)
141 1
        results = []
142 1
        for path in browsepaths:
143
            results.append(self._translate_browsepath_to_nodeid(path))
144 1
        return results
145 1
146 1
    def _translate_browsepath_to_nodeid(self, path):
147 1
        self.logger.debug("looking at path: %s", path)
148 1
        res = ua.BrowsePathResult()
149 1
        if path.StartingNode not in self._aspace:
150 1
            res.StatusCode = ua.StatusCode(ua.StatusCodes.BadNodeIdInvalid)
151 1
            return res
152 1
        current = path.StartingNode
153 1
        for el in path.RelativePath.Elements:
154 1
            nodeid = self._find_element_in_node(el, current)
155 1
            if not nodeid:
156 1
                res.StatusCode = ua.StatusCode(ua.StatusCodes.BadNoMatch)
157 1
                return res
158 1
            current = nodeid
159 1
        target = ua.BrowsePathTarget()
160 1
        target.TargetId = current
161 1
        target.RemainingPathIndex = 4294967295
162
        res.Targets = [target]
163 1
        return res
164 1
165 1
    def _find_element_in_node(self, el, nodeid):
166
        nodedata = self._aspace[nodeid]
167 1
        for ref in nodedata.references:
168 1
            # FIXME: here we should check other arguments!!
169 1
            if ref.BrowseName == el.TargetName:
170 1
                return ref.NodeId
171
        self.logger.info("element %s was not found in node %s", el, nodeid)
172
        return None
173 1
174
175 1
class NodeManagementService(object):
176 1
177 1
    def __init__(self, aspace):
178
        self.logger = logging.getLogger(__name__)
179 1
        self._aspace = aspace
180 1
181 1
    def add_nodes(self, addnodeitems, user=User.Admin):
182 1
        results = []
183 1
        for item in addnodeitems:
184
            results.append(self._add_node(item, user))
185 1
        return results
186 1
187
    def _add_node(self, item, user):
188
        result = ua.AddNodesResult()
189
190
        # If Identifier of requested NodeId is null we generate a new NodeId using
191 1
        # the namespace of the nodeid, this is an extention of the spec to allow
192 1
        # to requests the server to generate a new nodeid in a specified namespace
193 1
        if item.RequestedNewNodeId.has_null_identifier():
194
            self.logger.debug("RequestedNewNodeId has null identifier, generating Identifier")
195 1
            nodedata = NodeData(self._aspace.generate_nodeid(item.RequestedNewNodeId.NamespaceIndex))
196
        else:
197 1
            nodedata = NodeData(item.RequestedNewNodeId)
198 1
199 1
        if nodedata.nodeid in self._aspace:
200 1
            self.logger.warning("AddNodesItem: node already exists")
201
            result.StatusCode = ua.StatusCode(ua.StatusCodes.BadNodeIdExists)
202 1
            return result
203
204
        if item.ParentNodeId.is_null():
205 1
            # self.logger.warning("add_node: creating node %s without parent", nodedata.nodeid)
206 1
            # should return Error here, but the standard namespace define many nodes without parents...
207 1
            pass
208 1
        elif item.ParentNodeId not in self._aspace:
209 1
            self.logger.warning("add_node: while adding node %s, requested parent node %s does not exists", nodedata.nodeid, item.ParentNodeId)
210
            result.StatusCode = ua.StatusCode(ua.StatusCodes.BadParentNodeIdInvalid)
211 1
            return result
212 1
213 1
        if not user == User.Admin:
214
            result.StatusCode = ua.StatusCode(ua.StatusCodes.BadUserAccessDenied)
215 1
            return result
216
217
        self._add_node_attributes(nodedata, item)
218 1
219
        # now add our node to db
220 1
        self._aspace[nodedata.nodeid] = nodedata
221 1
222 1
        if not item.ParentNodeId.is_null():
223
            self._add_ref_from_parent(nodedata, item)
224
            self._add_ref_to_parent(nodedata, item, user)
225 1
226 1
        # add type definition
227
        if item.TypeDefinition != ua.NodeId():
228 1
            self._add_type_definition(nodedata, item, user)
229 1
230
        result.StatusCode = ua.StatusCode()
231 1
        result.AddedNodeId = nodedata.nodeid
232
233 1
        return result
234
235 1
    def _add_node_attributes(self, nodedata, item):
236
        # add common attrs
237
        nodedata.attributes[ua.AttributeIds.NodeId] = AttributeValue(
238 1
            ua.DataValue(ua.Variant(nodedata.nodeid, ua.VariantType.NodeId))
239
        )
240
        nodedata.attributes[ua.AttributeIds.BrowseName] = AttributeValue(
241 1
            ua.DataValue(ua.Variant(item.BrowseName, ua.VariantType.QualifiedName))
242
        )
243
        nodedata.attributes[ua.AttributeIds.NodeClass] = AttributeValue(
244
            ua.DataValue(ua.Variant(item.NodeClass, ua.VariantType.Int32))
245 1
        )
246
        # add requested attrs
247 1
        self._add_nodeattributes(item.NodeAttributes, nodedata)
248 1
249 1
    def _add_ref_from_parent(self, nodedata, item):
250 1
        desc = ua.ReferenceDescription()
251 1
        desc.ReferenceTypeId = item.ReferenceTypeId
252 1
        desc.NodeId = nodedata.nodeid
253 1
        desc.NodeClass = item.NodeClass
254 1
        desc.BrowseName = item.BrowseName
255 1
        desc.DisplayName = ua.LocalizedText(item.BrowseName.Name)
256 1
        desc.TypeDefinition = item.TypeDefinition
257
        desc.IsForward = True
258 1
        self._aspace[item.ParentNodeId].references.append(desc)
259 1
260 1
    def _add_ref_to_parent(self, nodedata, item, user):
261 1
        addref = ua.AddReferencesItem()
262 1
        addref.ReferenceTypeId = item.ReferenceTypeId
263 1
        addref.SourceNodeId = nodedata.nodeid
264 1
        addref.TargetNodeId = item.ParentNodeId
265 1
        addref.TargetNodeClass = self._aspace[item.ParentNodeId].attributes[ua.AttributeIds.NodeClass].value.Value.Value
266
        addref.IsForward = False
267 1
        self._add_reference(addref, user)
268 1
269 1
    def _add_type_definition(self, nodedata, item, user):
270 1
        addref = ua.AddReferencesItem()
271 1
        addref.SourceNodeId = nodedata.nodeid
272 1
        addref.IsForward = True
273 1
        addref.ReferenceTypeId = ua.NodeId(ua.ObjectIds.HasTypeDefinition)
274 1
        addref.TargetNodeId = item.TypeDefinition
275
        addref.TargetNodeClass = ua.NodeClass.DataType
276 1
        self._add_reference(addref, user)
277 1
278 1
    def delete_nodes(self, deletenodeitems, user=User.Admin):
279 1
        results = []
280 1
        for item in deletenodeitems.NodesToDelete:
281
            results.append(self._delete_node(item, user))
282 1
        return results
283 1
284
    def _delete_node(self, item, user):
285
        if user != User.Admin:
286 1
            return ua.StatusCode(ua.StatusCodes.BadUserAccessDenied)
287
288
        if item.NodeId not in self._aspace:
289
            self.logger.warning("DeleteNodesItem: node does not exists")
290 1
            return ua.StatusCode(ua.StatusCodes.BadNodeIdUnknown)
291 1
292 1
        if item.DeleteTargetReferences:
293 1
            for elem in self._aspace.keys():
294 1
                for rdesc in self._aspace[elem].references:
295
                    if rdesc.NodeId == item.NodeId:
296 1
                        self._aspace[elem].references.remove(rdesc)
297
298 1
        self._delete_node_callbacks(self._aspace[item.NodeId])
299
300 1
        del(self._aspace[item.NodeId])
301
302 1
        return ua.StatusCode()
303 1
304 1
    def _delete_node_callbacks(self, nodedata):
305
        if ua.AttributeIds.Value in nodedata.attributes:
306
            for handle, callback in nodedata.attributes[ua.AttributeIds.Value].datachange_callbacks.items():
307
                try:
308
                    callback(handle, None, ua.StatusCode(ua.StatusCodes.BadNodeIdUnknown))
309
                    self._aspace.delete_datachange_callback(handle)
310
                except Exception as ex:
311 1
                    self.logger.exception("Error calling delete node callback callback %s, %s, %s", nodedata, ua.AttributeIds.Value, ex)
312 1
313 1
    def add_references(self, refs, user=User.Admin):
314 1
        result = []
315 1
        for ref in refs:
316
            result.append(self._add_reference(ref, user))
317 1
        return result
318 1
319
    def _add_reference(self, addref, user):
320 1
        if addref.SourceNodeId not in self._aspace:
321 1
            return ua.StatusCode(ua.StatusCodes.BadSourceNodeIdInvalid)
322 1
        if addref.TargetNodeId not in self._aspace:
323
            return ua.StatusCode(ua.StatusCodes.BadTargetNodeIdInvalid)
324 1
        if user != User.Admin:
325 1
            return ua.StatusCode(ua.StatusCodes.BadUserAccessDenied)
326 1
        rdesc = ua.ReferenceDescription()
327 1
        rdesc.ReferenceTypeId = addref.ReferenceTypeId
328 1
        rdesc.IsForward = addref.IsForward
329 1
        rdesc.NodeId = addref.TargetNodeId
330 1
        rdesc.NodeClass = addref.TargetNodeClass
331 1
        bname = self._aspace.get_attribute_value(addref.TargetNodeId, ua.AttributeIds.BrowseName).Value.Value
332 1
        if bname:
333 1
            rdesc.BrowseName = bname
334 1
        dname = self._aspace.get_attribute_value(addref.TargetNodeId, ua.AttributeIds.DisplayName).Value.Value
335 1
        if dname:
336 1
            rdesc.DisplayName = dname
337
        self._aspace[addref.SourceNodeId].references.append(rdesc)
338 1
        return ua.StatusCode()
339
340
    def delete_references(self, refs, user=User.Admin):
341
        result = []
342
        for ref in refs:
343
            result.append(self._delete_reference(ref, user))
344 1
        return result
345
346
    def _delete_reference(self, item, user):
347
        if item.SourceNodeId not in self._aspace:
348
            return ua.StatusCode(ua.StatusCodes.BadSourceNodeIdInvalid)
349
        if item.TargetNodeId not in self._aspace:
350
            return ua.StatusCode(ua.StatusCodes.BadTargetNodeIdInvalid)
351
        if user != User.Admin:
352
            return ua.StatusCode(ua.StatusCodes.BadUserAccessDenied)
353
354
        for rdesc in self._aspace[item.SourceNodeId].references:
355
            if rdesc.NodeId is item.TargetNodeId:
356
                if rdesc.RefrenceTypeId != item.RefrenceTypeId:
357
                    return ua.StatusCode(ua.StatusCodes.BadReferenceTypeIdInvalid)
358
                if rdesc.IsForward == item.IsForward or item.DeleteBidirectional:
359
                    self._aspace[item.SourceNodeId].references.remove(rdesc)
360
361
        for rdesc in self._aspace[item.TargetNodeId].references:
362
            if rdesc.NodeId is item.SourceNodeId:
363
                if rdesc.RefrenceTypeId != item.RefrenceTypeId:
364
                    return ua.StatusCode(ua.StatusCodes.BadReferenceTypeIdInvalid)
365
                if rdesc.IsForward == item.IsForward or item.DeleteBidirectional:
366
                    self._aspace[item.SourceNodeId].references.remove(rdesc)
367
368 1
        return ua.StatusCode()
369 1
370 1
    def _add_node_attr(self, item, nodedata, name, vtype=None):
371 1
        if item.SpecifiedAttributes & getattr(ua.NodeAttributesMask, name):
372 1
            dv = ua.DataValue(ua.Variant(getattr(item, name), vtype))
373 1
            dv.ServerTimestamp = datetime.utcnow()
374
            dv.SourceTimestamp = datetime.utcnow()
375 1
            nodedata.attributes[getattr(ua.AttributeIds, name)] = AttributeValue(dv)
376 1
377 1
    def _add_nodeattributes(self, item, nodedata):
378 1
        self._add_node_attr(item, nodedata, "AccessLevel", ua.VariantType.Byte)
379 1
        self._add_node_attr(item, nodedata, "ArrayDimensions", ua.VariantType.UInt32)
380 1
        self._add_node_attr(item, nodedata, "BrowseName", ua.VariantType.QualifiedName)
381 1
        self._add_node_attr(item, nodedata, "ContainsNoLoops", ua.VariantType.Boolean)
382 1
        self._add_node_attr(item, nodedata, "DataType", ua.VariantType.NodeId)
383 1
        self._add_node_attr(item, nodedata, "Description", ua.VariantType.LocalizedText)
384 1
        self._add_node_attr(item, nodedata, "DisplayName", ua.VariantType.LocalizedText)
385 1
        self._add_node_attr(item, nodedata, "EventNotifier", ua.VariantType.Byte)
386 1
        self._add_node_attr(item, nodedata, "Executable", ua.VariantType.Boolean)
387 1
        self._add_node_attr(item, nodedata, "Historizing", ua.VariantType.Boolean)
388 1
        self._add_node_attr(item, nodedata, "InverseName", ua.VariantType.LocalizedText)
389 1
        self._add_node_attr(item, nodedata, "IsAbstract", ua.VariantType.Boolean)
390 1
        self._add_node_attr(item, nodedata, "MinimumSamplingInterval", ua.VariantType.Double)
391 1
        self._add_node_attr(item, nodedata, "NodeClass", ua.VariantType.UInt32)
392 1
        self._add_node_attr(item, nodedata, "NodeId", ua.VariantType.NodeId)
393 1
        self._add_node_attr(item, nodedata, "Symmetric", ua.VariantType.Boolean)
394 1
        self._add_node_attr(item, nodedata, "UserAccessLevel", ua.VariantType.Byte)
395 1
        self._add_node_attr(item, nodedata, "UserExecutable", ua.VariantType.Boolean)
396 1
        self._add_node_attr(item, nodedata, "UserWriteMask", ua.VariantType.Byte)
397 1
        self._add_node_attr(item, nodedata, "ValueRank", ua.VariantType.Int32)
398 1
        self._add_node_attr(item, nodedata, "WriteMask", ua.VariantType.UInt32)
399
        self._add_node_attr(item, nodedata, "UserWriteMask", ua.VariantType.UInt32)
400
        self._add_node_attr(item, nodedata, "Value")
401 1
402
403 1
class MethodService(object):
404 1
405 1
    def __init__(self, aspace):
406
        self.logger = logging.getLogger(__name__)
407 1
        self._aspace = aspace
408 1
409 1
    def call(self, methods):
410 1
        results = []
411 1
        for method in methods:
412
            results.append(self._call(method))
413 1
        return results
414 1
415 1
    def _call(self, method):
416 1
        res = ua.CallMethodResult()
417
        if method.ObjectId not in self._aspace or method.MethodId not in self._aspace:
418 1
            res.StatusCode = ua.StatusCode(ua.StatusCodes.BadNodeIdInvalid)
419 1
        else:
420
            node = self._aspace[method.MethodId]
421
            if node.call is None:
422 1
                res.StatusCode = ua.StatusCode(ua.StatusCodes.BadNothingToDo)
423 1
            else:
424 1
                try:
425 1
                    res.OutputArguments = node.call(method.ObjectId, *method.InputArguments)
426 1
                    for _ in method.InputArguments:
427 1
                        res.InputArgumentResults.append(ua.StatusCode())
428 1
                except Exception:
429 1
                    self.logger.exception("Error executing method call %s, an exception was raised: ", method)
430
                    res.StatusCode = ua.StatusCode(ua.StatusCodes.BadUnexpectedError)
431
        return res
432 1
433
434
class AddressSpace(object):
435
436
    """
437
    The address space object stores all the nodes og the OPC-UA server
438
    and helper methods.
439
    The methods are threadsafe
440 1
    """
441 1
442 1
    def __init__(self):
443 1
        self.logger = logging.getLogger(__name__)
444 1
        self._nodes = {}
445 1
        self._lock = RLock()  # FIXME: should use multiple reader, one writter pattern
446 1
        self._datachange_callback_counter = 200
447 1
        self._handle_to_attribute_map = {}
448
        self._default_idx = 2
449 1
        self._nodeid_counter = {0: 20000, 1: 2000}
450 1
451 1
    def __getitem__(self, nodeid):
452
        with self._lock:
453 1
            if nodeid in self._nodes:
454 1
                return self._nodes.__getitem__(nodeid)
455 1
456
    def __setitem__(self, nodeid, value):
457 1
        with self._lock:
458 1
            return self._nodes.__setitem__(nodeid, value)
459 1
460
    def __contains__(self, nodeid):
461 1
        with self._lock:
462 1
            return self._nodes.__contains__(nodeid)
463 1
464
    def __delitem__(self, nodeid):
465 1
        with self._lock:
466 1
            self._nodes.__delitem__(nodeid)
467 1
468 1
    def generate_nodeid(self, idx=None):
469 1
        if idx is None:
470
            idx = self._default_idx
471 1
        if idx in self._nodeid_counter:
472 1
            self._nodeid_counter[idx] += 1
473 1
        else:
474
            self._nodeid_counter[idx] = 1
475 1
        nodeid = ua.NodeId(self._nodeid_counter[idx], idx)
476
        with self._lock:  # OK since reentrant lock
477
            while True:
478
                if nodeid in self._nodes:
479
                    nodeid = self.generate_nodeid(idx)
480
                else:
481
                    return nodeid
482
483
    def keys(self):
484 1
        with self._lock:
485
            return self._nodes.keys()
486
487
    def empty(self):
488
        """
489
        Delete all nodes in address space
490
        """
491
        with self._lock:
492
            self._nodes = {}
493
494
    def dump(self, path):
495
        """
496
        dump address space as binary to file
497
        """
498
        s = shelve.open(path, "n", protocol = pickle.HIGHEST_PROTOCOL)
499
        for nodeid in self._nodes.keys():
500
            s[nodeid.to_string()] = self._nodes[nodeid]
501
        s.close()
502
503
    def load(self, path):
504
        """
505
        load address space from file, overwritting everything current address space
506
        """
507
        class LazyLoadingDict(collections.MutableMapping):
508
            def __init__(self, source):
509
                self.source = source
510
                self.cache = {}
511
512
            def __getitem__(self, key):
513
                try:
514
                    return self.cache[key]
515
                except KeyError:
516
                    node = self.cache[key] = self.source[key.to_string()]
517 1
                    return node
518 1
519 1
            def __setitem__(self, key, value):
520 1
                self.cache[key] = value
521 1
522 1
            def __contains__(self, key):
523 1
                return key in self.cache or key.to_string() in self.source
524 1
525 1
            def __delitem__(self, key):
526 1
                raise NotImplementedError
527 1
528 1
            def __iter__(self):
529 1
                raise NotImplementedError
530 1
531
            def __len__(self):
532 1
                raise NotImplementedError
533
534 1
        self._nodes = LazyLoadingDict(shelve.open(path, "r"))
535 1
536 1
    def get_attribute_value(self, nodeid, attr):
537 1
        with self._lock:
538 1
            self.logger.debug("get attr val: %s %s", nodeid, attr)
539 1
            if nodeid not in self._nodes:
540 1
                dv = ua.DataValue()
541 1
                dv.StatusCode = ua.StatusCode(ua.StatusCodes.BadNodeIdUnknown)
542 1
                return dv
543 1
            node = self._nodes[nodeid]
544 1
            if attr not in node.attributes:
545 1
                dv = ua.DataValue()
546
                dv.StatusCode = ua.StatusCode(ua.StatusCodes.BadAttributeIdInvalid)
547 1
                return dv
548 1
            attval = node.attributes[attr]
549 1
            if attval.value_callback:
550 1
                return attval.value_callback()
551 1
            return attval.value
552 1
553
    def set_attribute_value(self, nodeid, attr, value):
554 1
        with self._lock:
555 1
            self.logger.debug("set attr val: %s %s %s", nodeid, attr, value)
556 1
            if nodeid not in self._nodes:
557
                return ua.StatusCode(ua.StatusCodes.BadNodeIdUnknown)
558
            node = self._nodes[nodeid]
559
            if attr not in node.attributes:
560 1
                return ua.StatusCode(ua.StatusCodes.BadAttributeIdInvalid)
561
            if not value.SourceTimestamp:
562 1
                value.SourceTimestamp = datetime.utcnow()
563 1
            if not value.ServerTimestamp:
564 1
                value.ServerTimestamp = datetime.utcnow()
565 1
566
            attval = node.attributes[attr]
567 1
            old = attval.value
568 1
            attval.value = value
569 1
            cbs = []
570 1
            if old.Value != value.Value:  # only send call callback when a value change has happend
571 1
                cbs = list(attval.datachange_callbacks.items())
572 1
573 1
        for k, v in cbs:
574 1
            try:
575 1
                v(k, value)
576
            except Exception as ex:
577 1
                self.logger.exception("Error calling datachange callback %s, %s, %s", k, v, ex)
578 1
579 1
        return ua.StatusCode()
580 1
581
    def add_datachange_callback(self, nodeid, attr, callback):
582 1
        with self._lock:
583 1
            self.logger.debug("set attr callback: %s %s %s", nodeid, attr, callback)
584 1
            if nodeid not in self._nodes:
585 1
                return ua.StatusCode(ua.StatusCodes.BadNodeIdUnknown), 0
586
            node = self._nodes[nodeid]
587
            if attr not in node.attributes:
588
                return ua.StatusCode(ua.StatusCodes.BadAttributeIdInvalid), 0
589
            attval = node.attributes[attr]
590
            self._datachange_callback_counter += 1
591
            handle = self._datachange_callback_counter
592
            attval.datachange_callbacks[handle] = callback
593
            self._handle_to_attribute_map[handle] = (nodeid, attr)
594
            return ua.StatusCode(), handle
595
596
    def delete_datachange_callback(self, handle):
597
        with self._lock:
598
            nodeid, attr = self._handle_to_attribute_map.pop(handle)
599
            self._nodes[nodeid].attributes[attr].datachange_callbacks.pop(handle)
600
601
    def add_method_callback(self, methodid, callback):
602
        with self._lock:
603
            node = self._nodes[methodid]
604
            node.call = callback
605