Completed
Push — master ( 73a2fe...52074e )
by Olivier
03:50
created

Node._get_path()   A

Complexity

Conditions 4

Size

Total Lines 20

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 7
CRAP Score 4

Importance

Changes 0
Metric Value
cc 4
c 0
b 0
f 0
dl 0
loc 20
rs 9.2
ccs 7
cts 7
cp 1
crap 4
1
"""
2
High level node object, to access node attribute
3
and browse address space
4
"""
5
6 1
from opcua import ua
7
from opcua.common import events
8 1
import opcua.common
9
10
class Node(object):
11 1
12
    """
13
    High level node object, to access node attribute,
14
    browse and populate address space.
15
    Node objects are usefull as-is but they do not expose the entire
16
    OPC-UA protocol. Feel free to look at the code of this class and call
17
    directly UA services methods to optimize your code
18
    """
19
20
    def __init__(self, server, nodeid):
21 1
        self.server = server
22 1
        self.nodeid = None
23 1
        if isinstance(nodeid, Node):
24 1
            self.nodeid = nodeid.nodeid
25 1
        elif isinstance(nodeid, ua.NodeId):
26 1
            self.nodeid = nodeid
27 1
        elif type(nodeid) in (str, bytes):
28 1
            self.nodeid = ua.NodeId.from_string(nodeid)
29 1
        elif isinstance(nodeid, int):
30
            self.nodeid = ua.NodeId(nodeid, 0)
31
        else:
32
            raise ua.UaError("argument to node must be a NodeId object or a string defining a nodeid found {} of type {}".format(nodeid, type(nodeid)))
33 1
34 1
    def __eq__(self, other):
35 1
        if isinstance(other, Node) and self.nodeid == other.nodeid:
36 1
            return True
37
        return False
38 1
39
    def __ne__(self, other):
40
        return not self.__eq__(other)
41 1
42
    def __str__(self):
43 1
        return "Node({})".format(self.nodeid)
44
    __repr__ = __str__
45 1
46 1
    def __hash__(self):
47
        return self.nodeid.__hash__()
48 1
49
    def get_browse_name(self):
50
        """
51
        Get browse name of a node. A browse name is a QualifiedName object
52
        composed of a string(name) and a namespace index.
53 1
        """
54 1
        result = self.get_attribute(ua.AttributeIds.BrowseName)
55
        return result.Value.Value
56 1
57
    def get_display_name(self):
58
        """
59
        get description attribute of node
60 1
        """
61 1
        result = self.get_attribute(ua.AttributeIds.DisplayName)
62
        return result.Value.Value
63 1
64
    def get_data_type(self):
65
        """
66
        get data type of node as NodeId
67 1
        """
68 1
        result = self.get_attribute(ua.AttributeIds.DataType)
69
        return result.Value.Value
70 1
71
    def get_data_type_as_variant_type(self):
72
        """
73
        get data type of node as VariantType
74
        This only works if node is a variable, otherwise type
75
        may not be convertible to VariantType
76
        """
77 1
        result = self.get_attribute(ua.AttributeIds.DataType)
78
        return ua.datatype_to_varianttype(result.Value.Value)
79
80
    def get_access_level(self):
81
        """
82
        Get the access level attribute of the node as a set of AccessLevel enum values.
83
        """
84 1
        result = self.get_attribute(ua.AttributeIds.AccessLevel)
85
        return ua.AccessLevel.parse_bitfield(result.Value.Value)
86
87
    def get_user_access_level(self):
88
        """
89 1
        Get the user access level attribute of the node as a set of AccessLevel enum values.
90 1
        """
91
        result = self.get_attribute(ua.AttributeIds.UserAccessLevel)
92 1
        return ua.AccessLevel.parse_bitfield(result.Value.Value)
93
94
    def get_event_notifier(self):
95
        """
96
        Get the event notifier attribute of the node as a set of EventNotifier enum values.
97
        """
98 1
        result = self.get_attribute(ua.AttributeIds.EventNotifier)
99
        return ua.EventNotifier.parse_bitfield(result.Value.Value)
100 1
101
    def set_event_notifier(self, values):
102
        """
103
        Set the event notifier attribute.
104
105 1
        :param values: an iterable of EventNotifier enum values.
106 1
        """
107
        event_notifier_bitfield = ua.EventNotifier.to_bitfield(values)
108 1
        self.set_attribute(ua.AttributeIds.EventNotifier, ua.DataValue(ua.Variant(event_notifier_bitfield, ua.VariantType.Byte)))
109
110
    def get_node_class(self):
111
        """
112 1
        get node class attribute of node
113 1
        """
114
        result = self.get_attribute(ua.AttributeIds.NodeClass)
115 1
        return result.Value.Value
116
117
    def get_description(self):
118
        """
119 1
        get description attribute class of node
120 1
        """
121
        result = self.get_attribute(ua.AttributeIds.Description)
122 1
        return result.Value.Value
123
124
    def get_value(self):
125
        """
126 1
        Get value of a node as a python type. Only variables ( and properties) have values.
127 1
        An exception will be generated for other node types.
128
        """
129 1
        result = self.get_data_value()
130
        return result.Value.Value
131
132
    def get_data_value(self):
133
        """
134
        Get value of a node as a DataValue object. Only variables (and properties) have values.
135
        An exception will be generated for other node types.
136
        DataValue contain a variable value as a variant as well as server and source timestamps
137
        """
138
        return self.get_attribute(ua.AttributeIds.Value)
139 1
140 1
    def set_array_dimensions(self, value):
141 1
        """
142 1
        Set attribute ArrayDimensions of node
143 1
        make sure it has the correct data type
144
        """
145 1
        v = ua.Variant(value, ua.VariantType.UInt32)
146 1
        self.set_attribute(ua.AttributeIds.ArrayDimensions, ua.DataValue(v))
147
148 1
    def get_array_dimensions(self):
149
        """
150 1
        Read and return ArrayDimensions attribute of node
151
        """
152
        res = self.get_attribute(ua.AttributeIds.ArrayDimensions)
153
        return res.Value.Value
154
155 1
    def set_value_rank(self, value):
156 1
        """
157 1
        Set attribute ArrayDimensions of node
158
        """
159 1
        v = ua.Variant(value, ua.VariantType.Int32)
160 1
        self.set_attribute(ua.AttributeIds.ValueRank, ua.DataValue(v))
161
162 1
    def get_value_rank(self):
163 1
        """
164 1
        Read and return ArrayDimensions attribute of node
165 1
        """
166
        res = self.get_attribute(ua.AttributeIds.ValueRank)
167 1
        return res.Value.Value
168 1
169 1
    def set_value(self, value, varianttype=None):
170 1
        """
171
        Set value of a node. Only variables(properties) have values.
172 1
        An exception will be generated for other node types.
173
        value argument is either:
174
        * a python built-in type, converted to opc-ua
175
        optionnaly using the variantype argument.
176
        * a ua.Variant, varianttype is then ignored
177
        * a ua.DataValue, you then have full control over data send to server
178
        """
179 1
        datavalue = None
180
        if isinstance(value, ua.DataValue):
181
            datavalue = value
182
        elif isinstance(value, ua.Variant):
183
            datavalue = ua.DataValue(value)
184
        else:
185 1
            datavalue = ua.DataValue(ua.Variant(value, varianttype))
186 1
        self.set_attribute(ua.AttributeIds.Value, datavalue)
187 1
188 1
    set_data_value = set_value
189 1
190 1
    def set_writable(self, writable=True):
191 1
        """
192 1
        Set node as writable by clients.
193
        A node is always writable on server side.
194 1
        """
195
        if writable:
196
            self.set_attr_bit(ua.AttributeIds.AccessLevel, ua.AccessLevel.CurrentWrite)
197
            self.set_attr_bit(ua.AttributeIds.UserAccessLevel, ua.AccessLevel.CurrentWrite)
198
        else:
199 1
            self.unset_attr_bit(ua.AttributeIds.AccessLevel, ua.AccessLevel.CurrentWrite)
200 1
            self.unset_attr_bit(ua.AttributeIds.UserAccessLevel, ua.AccessLevel.CurrentWrite)
201 1
202 1
    def set_attr_bit(self, attr, bit):
203 1
        val = self.get_attribute(attr)
204 1
        val.Value.Value = ua.ua_binary.set_bit(val.Value.Value, bit)
205 1
        self.set_attribute(attr, val)
206 1
207
    def unset_attr_bit(self, attr, bit):
208 1
        val = self.get_attribute(attr)
209
        val.Value.Value = ua.ua_binary.unset_bit(val.Value.Value, bit)
210
        self.set_attribute(attr, val)
211
212
    def set_read_only(self):
213
        """
214
        Set a node as read-only for clients.
215
        A node is always writable on server side.
216
        """
217
        return self.set_writable(False)
218
219
    def set_attribute(self, attributeid, datavalue):
220
        """
221
        Set an attribute of a node
222
        attributeid is a member of ua.AttributeIds
223 1
        datavalue is a ua.DataValue object
224
        """
225
        attr = ua.WriteValue()
226
        attr.NodeId = self.nodeid
227
        attr.AttributeId = attributeid
228
        attr.Value = datavalue
229
        params = ua.WriteParameters()
230
        params.NodesToWrite = [attr]
231
        result = self.server.write(params)
232
        result[0].check()
233
234
    def get_attribute(self, attr):
235
        """
236
        Read one attribute of a node
237
        result code from server is checked and an exception is raised in case of error
238
        """
239
        rv = ua.ReadValueId()
240
        rv.NodeId = self.nodeid
241
        rv.AttributeId = attr
242
        params = ua.ReadParameters()
243
        params.NodesToRead.append(rv)
244
        result = self.server.read(params)
245 1
        result[0].StatusCode.check()
246
        return result[0]
247 1
248
    def get_attributes(self, attrs):
249
        """
250
        Read several attributes of a node
251
        list of DataValue is returned
252 1
        """
253
        params = ua.ReadParameters()
254 1
        for attr in attrs:
255
            rv = ua.ReadValueId()
256
            rv.NodeId = self.nodeid
257 1
            rv.AttributeId = attr
258
            params.NodesToRead.append(rv)
259
260
        results = self.server.read(params)
261
        return results
262
263
    def get_children(self, refs=ua.ObjectIds.HierarchicalReferences, nodeclassmask=ua.NodeClass.Unspecified):
264
        """
265
        Get all children of a node. By default hierarchical references and all node classes are returned.
266 1
        Other reference types may be given:
267 1
        References = 31
268 1
        NonHierarchicalReferences = 32
269 1
        HierarchicalReferences = 33
270 1
        HasChild = 34
271 1
        Organizes = 35
272
        HasEventSource = 36
273 1
        HasModellingRule = 37
274 1
        HasEncoding = 38
275 1
        HasDescription = 39
276 1
        HasTypeDefinition = 40
277 1
        GeneratesEvent = 41
278 1
        Aggregates = 44
279
        HasSubtype = 45
280 1
        HasProperty = 46
281
        HasComponent = 47
282
        HasNotifier = 48
283
        HasOrderedComponent = 49
284
        """
285
        return self.get_referenced_nodes(refs, ua.BrowseDirection.Forward, nodeclassmask)
286 1
287 1
    def get_properties(self):
288 1
        """
289 1
        return properties of node.
290 1
        properties are child nodes with a reference of type HasProperty and a NodeClass of Variable
291 1
        """
292
        return self.get_children(refs=ua.ObjectIds.HasProperty, nodeclassmask=ua.NodeClass.Variable)
293 1
294
    def get_variables(self):
295
        """
296
        return variables of node.
297 1
        properties are child nodes with a reference of type HasComponent and a NodeClass of Variable
298 1
        """
299 1
        return self.get_children(refs=ua.ObjectIds.HasComponent, nodeclassmask=ua.NodeClass.Variable)
300 1
301
    def get_methods(self):
302 1
        """
303
        return methods of node.
304
        properties are child nodes with a reference of type HasComponent and a NodeClass of Method
305
        """
306 1
        return self.get_children(refs=ua.ObjectIds.HasComponent, nodeclassmask=ua.NodeClass.Method)
307
308 1
    def get_children_descriptions(self, refs=ua.ObjectIds.HierarchicalReferences, nodeclassmask=ua.NodeClass.Unspecified, includesubtypes=True):
309
        return self.get_references(refs, ua.BrowseDirection.Forward, nodeclassmask, includesubtypes)
310 1
311
    def get_references(self, refs=ua.ObjectIds.References, direction=ua.BrowseDirection.Both, nodeclassmask=ua.NodeClass.Unspecified, includesubtypes=True):
312
        """
313
        returns references of the node based on specific filter defined with:
314
315
        refs = ObjectId of the Reference
316
        direction = Browse direction for references
317
        nodeclassmask = filter nodes based on specific class
318
        includesubtypes = If true subtypes of the reference (ref) are also included
319 1
        """
320 1
        desc = ua.BrowseDescription()
321 1
        desc.BrowseDirection = direction
322 1
        desc.ReferenceTypeId = ua.TwoByteNodeId(refs)
323 1
        desc.IncludeSubtypes = includesubtypes
324 1
        desc.NodeClassMask = nodeclassmask
325 1
        desc.ResultMask = ua.BrowseResultMask.All
326 1
327 1
        desc.NodeId = self.nodeid
328
        params = ua.BrowseParameters()
329 1
        params.View.Timestamp = ua.get_win_epoch()
330
        params.NodesToBrowse.append(desc)
331 1
        results = self.server.browse(params)
332 1
        return results[0].References
333 1
334 1
    def get_referenced_nodes(self, refs=ua.ObjectIds.References, direction=ua.BrowseDirection.Both, nodeclassmask=ua.NodeClass.Unspecified, includesubtypes=True):
335 1
        """
336 1
        returns referenced nodes based on specific filter
337 1
        Paramters are the same as for get_references
338 1
339
        """
340
        references = self.get_references(refs, direction, nodeclassmask, includesubtypes)
341 1
        nodes = []
342 1
        for desc in references:
343 1
            node = Node(self.server, desc.NodeId)
344
            nodes.append(node)
345 1
        return nodes
346
347
    def get_type_definition(self):
348
        """
349
        returns type definition of the node.
350
        """
351
        references = self.get_references(refs=ua.ObjectIds.HasTypeDefinition, direction=ua.BrowseDirection.Forward)
352 1
        if len(references) == 0:
353 1
            return None
354 1
        return references[0].NodeId
355 1
356
    def get_path_as_string(self, max_length=20):
357 1
        """
358 1
        Attempt to find path of node from root node and return it as a list of strings.
359 1
        There might several possible paths to a node, this function will return one
360
        Some nodes may be missing references, so this method may
361 1
        return an empty list
362 1
        Since address space may have circular references, a max length is specified
363 1
364 1
        """
365 1
        path = self._get_path(max_length)
366
        path = [ref.BrowseName.to_string() for ref in path]
367 1
        path.append(self.get_browse_name().to_string())
368
        return path
369
370
    def get_path(self, max_length=20):
371
        """
372 1
        Attempt to find path of node from root node and return it as a list of Nodes.
373 1
        There might several possible paths to a node, this function will return one
374 1
        Some nodes may be missing references, so this method may
375
        return an empty list
376 1
        Since address space may have circular references, a max length is specified
377 1
378 1
        """
379 1
        path = self._get_path(max_length)
380 1
        path = [Node(self.server, ref.NodeId) for ref in path]
381 1
        path.append(self)
382 1
        return path
383
384 1
    def _get_path(self, max_length=20):
385
        """
386
        Attempt to find path of node from root node and return it as a list of Nodes.
387
        There might several possible paths to a node, this function will return one
388
        Some nodes may be missing references, so this method may
389
        return an empty list
390
        Since address space may have circular references, a max length is specified
391
392
        """
393
        path = []
394
        node = self
395
        while True:
396 1
            refs = node.get_references(refs=ua.ObjectIds.HierarchicalReferences, direction=ua.BrowseDirection.Inverse)
397 1
            if len(refs) > 0:
398 1
                path.insert(0, refs[0])
399
                node = Node(self.server, refs[0].NodeId)
400 1
                if len(path) >= (max_length -1):
401 1
                    return path
402 1
            else:
403
                return path
404 1
405 1
    def get_parent(self):
406
        """
407 1
        returns parent of the node.
408
        A Node may have several parents, the first found is returned.
409 1
        This method uses reverse references, a node might be missing such a link,
410 1
        thus we will not find its parent.
411
        """
412 1
        refs = self.get_references(refs=ua.ObjectIds.HierarchicalReferences, direction=ua.BrowseDirection.Inverse)
413
        if len(refs) > 0:
414
            return Node(self.server, refs[0].NodeId)
415
        else:
416
            return None
417 1
418 1
    def get_child(self, path):
419 1
        """
420
        get a child specified by its path from this node.
421 1
        A path might be:
422 1
        * a string representing a qualified name.
423 1
        * a qualified name
424 1
        * a list of string
425 1
        * a list of qualified names
426 1
        """
427 1
        if type(path) not in (list, tuple):
428
            path = [path]
429
        rpath = self._make_relative_path(path)
430
        bpath = ua.BrowsePath()
431
        bpath.StartingNode = self.nodeid
432
        bpath.RelativePath = rpath
433
        result = self.server.translate_browsepaths_to_nodeids([bpath])
434 1
        result = result[0]
435 1
        result.StatusCode.check()
436 1
        # FIXME: seems this method may return several nodes
437
        return Node(self.server, result.Targets[0].TargetId)
438 1
439 1
    def _make_relative_path(self, path):
440 1
        rpath = ua.RelativePath()
441
        for item in path:
442 1
            el = ua.RelativePathElement()
443 1
            el.ReferenceTypeId = ua.TwoByteNodeId(ua.ObjectIds.HierarchicalReferences)
444 1
            el.IsInverse = False
445
            el.IncludeSubtypes = True
446 1
            if isinstance(item, ua.QualifiedName):
447 1
                el.TargetName = item
448 1
            else:
449
                el.TargetName = ua.QualifiedName.from_string(item)
450 1
            rpath.Elements.append(el)
451 1
        return rpath
452 1
453
    def read_raw_history(self, starttime=None, endtime=None, numvalues=0):
454 1
        """
455 1
        Read raw history of a node
456 1
        result code from server is checked and an exception is raised in case of error
457
        If numvalues is > 0 and number of events in period is > numvalues
458 1
        then result will be truncated
459 1
        """
460 1
        details = ua.ReadRawModifiedDetails()
461
        details.IsReadModified = False
462
        if starttime:
463
            details.StartTime = starttime
464
        else:
465
            details.StartTime = ua.get_win_epoch()
466
        if endtime:
467
            details.EndTime = endtime
468
        else:
469
            details.EndTime = ua.get_win_epoch()
470
        details.NumValuesPerNode = numvalues
471
        details.ReturnBounds = True
472
        result = self.history_read(details)
473
        return result.HistoryData.DataValues
474
475 View Code Duplication
    def history_read(self, details):
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Loading history...
476
        """
477
        Read raw history of a node, low-level function
478
        result code from server is checked and an exception is raised in case of error
479
        """
480
        valueid = ua.HistoryReadValueId()
481
        valueid.NodeId = self.nodeid
482
        valueid.IndexRange = ''
483
484
        params = ua.HistoryReadParameters()
485
        params.HistoryReadDetails = details
486
        params.TimestampsToReturn = ua.TimestampsToReturn.Both
487
        params.ReleaseContinuationPoints = False
488
        params.NodesToRead.append(valueid)
489
        result = self.server.history_read(params)[0]
490
        return result
491
492
    def read_event_history(self, starttime=None, endtime=None, numvalues=0, evtypes=ua.ObjectIds.BaseEventType):
493
        """
494
        Read event history of a source node
495
        result code from server is checked and an exception is raised in case of error
496
        If numvalues is > 0 and number of events in period is > numvalues
497
        then result will be truncated
498
        """
499
500
        details = ua.ReadEventDetails()
501
        if starttime:
502
            details.StartTime = starttime
503
        else:
504
            details.StartTime = ua.get_win_epoch()
505
        if endtime:
506
            details.EndTime = endtime
507
        else:
508
            details.EndTime = ua.get_win_epoch()
509
        details.NumValuesPerNode = numvalues
510
511
        if not isinstance(evtypes, (list, tuple)):
512
            evtypes = [evtypes]
513
514
        evtypes = [Node(self.server, evtype) for evtype in evtypes]
515
516
        evfilter = events.get_filter_from_event_type(evtypes)
517
        details.Filter = evfilter
518
519
        result = self.history_read_events(details)
520
        event_res = []
521
        for res in result.HistoryData.Events:
522
            event_res.append(events.Event.from_event_fields(evfilter.SelectClauses, res.EventFields))
523
        return event_res
524
525 View Code Duplication
    def history_read_events(self, details):
0 ignored issues
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Loading history...
526
        """
527
        Read event history of a node, low-level function
528
        result code from server is checked and an exception is raised in case of error
529
        """
530
        valueid = ua.HistoryReadValueId()
531
        valueid.NodeId = self.nodeid
532
        valueid.IndexRange = ''
533
534
        params = ua.HistoryReadParameters()
535
        params.HistoryReadDetails = details
536
        params.TimestampsToReturn = ua.TimestampsToReturn.Both
537
        params.ReleaseContinuationPoints = False
538
        params.NodesToRead.append(valueid)
539
        result = self.server.history_read(params)[0]
540
        return result
541
542
    def delete(self, delete_references=True):
543
        """
544
        Delete node from address space
545
        """
546
        ditem = ua.DeleteNodesItem()
547
        ditem.NodeId = self.nodeid
548
        ditem.DeleteTargetReferences = delete_references
549
        params = ua.DeleteNodesParameters()
550
        params.NodesToDelete = [ditem]
551
        result = self.server.delete_nodes(params)
552
        result[0].check()
553
554
    def add_folder(self, nodeid, bname):
555
        return  opcua.common.manage_nodes.create_folder(self, nodeid, bname)
556
557
    def add_object(self, nodeid, bname, objecttype=None):
558
        return opcua.common.manage_nodes.create_object(self, nodeid, bname, objecttype)
559
560
    def add_variable(self, nodeid, bname, val, varianttype=None, datatype=None):
561
        return opcua.common.manage_nodes.create_variable(self, nodeid, bname, val, varianttype, datatype)
562
563
    def add_object_type(self, nodeid, bname):
564
        return opcua.common.manage_nodes.create_object_type(self, nodeid, bname)
565
566
    def add_variable_type(self, nodeid, bname, datatype):
567
        return opcua.common.manage_nodes.create_variable_type(self, nodeid, bname, datatype)
568
569
    def add_data_type(self, nodeid, bname, description=None):
570
        return opcua.common.manage_nodes.create_data_type(self, nodeid, bname, description=None)
571
572
    def add_property(self, nodeid, bname, val, varianttype=None, datatype=None):
573
        return opcua.common.manage_nodes.create_property(self, nodeid, bname, val, varianttype, datatype)
574
575
    def add_method(self, *args):
576
        return opcua.common.manage_nodes.create_method(self, *args)
577
578
    def add_reference_type(self, parent, nodeid, bname):
579
        return opcua.common.manage_nodes.create_reference_type(parent, nodeid, bname)
580
581
    def call_method(self, methodid, *args):
582
        return opcua.common.methods.call_method(self, methodid, *args)
583