Completed
Pull Request — master (#217)
by Olivier
04:21
created

Node.get_user_access_level()   A

Complexity

Conditions 1

Size

Total Lines 6

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 0
CRAP Score 2

Importance

Changes 0
Metric Value
cc 1
dl 0
loc 6
ccs 0
cts 2
cp 0
crap 2
rs 9.4285
c 0
b 0
f 0
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
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 VariantType
67 1
        """
68 1
        result = self.get_attribute(ua.AttributeIds.DataType)
69
        return ua.DataType_to_VariantType(result.Value.Value)
70 1
71
    def get_access_level(self):
72
        """
73
        get access level of node as a list of AccessLevel Enum
74
        """
75
        result = self.get_attribute(ua.AttributeIds.AccessLevel)
76
        return ua.int_to_AccessLevel(result.Value.Value)
77 1
78
    def get_user_access_level(self):
79
        """
80
        get user access level of node as a list of AccessLevel Enum
81
        """
82
        result = self.get_attribute(ua.AttributeIds.UserAccessLevel)
83
        return ua.int_to_AccessLevel(result.Value.Value)
84 1
85
    def get_event_notifier(self):
86
        """
87
        get EventNotifier attribute value as a list of EventNotifier Enum
88
        """
89 1
        result = self.get_attribute(ua.AttributeIds.EventNotifier)
90 1
        return ua.int_to_EventNotifier(result.Value.Value)
91
92 1
    def set_event_notifier(self, enum_list):
93
        """
94
        set event notifier attribute,
95
        arg is a list of EventNotifier Enum
96
        """
97
        res = 1
98 1
        for en in enum_list:
99
            ua.set_bit(res, en.value)
100 1
        self.set_attribute(ua.AttributeIds.EventNotifier, ua.DataValue(ua.Variant(res, ua.VariantType.Byte)))
101
102
    def get_node_class(self):
103
        """
104
        get node class attribute of node
105 1
        """
106 1
        result = self.get_attribute(ua.AttributeIds.NodeClass)
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        return result.Value.Value
108 1
109
    def get_description(self):
110
        """
111
        get description attribute class of node
112 1
        """
113 1
        result = self.get_attribute(ua.AttributeIds.Description)
114
        return result.Value.Value
115 1
116
    def get_value(self):
117
        """
118
        Get value of a node as a python type. Only variables ( and properties) have values.
119 1
        An exception will be generated for other node types.
120 1
        """
121
        result = self.get_data_value()
122 1
        return result.Value.Value
123
124
    def get_data_value(self):
125
        """
126 1
        Get value of a node as a DataValue object. Only variables (and properties) have values.
127 1
        An exception will be generated for other node types.
128
        DataValue contain a variable value as a variant as well as server and source timestamps
129 1
        """
130
        return self.get_attribute(ua.AttributeIds.Value)
131
132
    def set_array_dimensions(self, value):
133
        """
134
        Set attribute ArrayDimensions of node
135
        make sure it has the correct data type
136
        """
137
        v = ua.Variant(value, ua.VariantType.UInt32)
138
        self.set_attribute(ua.AttributeIds.ArrayDimensions, ua.DataValue(v))
139 1
140 1
    def get_array_dimensions(self):
141 1
        """
142 1
        Read and return ArrayDimensions attribute of node
143 1
        """
144
        res = self.get_attribute(ua.AttributeIds.ArrayDimensions)
145 1
        return res.Value.Value
146 1
147
    def set_value_rank(self, value):
148 1
        """
149
        Set attribute ArrayDimensions of node
150 1
        """
151
        v = ua.Variant(value, ua.VariantType.Int32)
152
        self.set_attribute(ua.AttributeIds.ValueRank, ua.DataValue(v))
153
154
    def get_value_rank(self):
155 1
        """
156 1
        Read and return ArrayDimensions attribute of node
157 1
        """
158
        res = self.get_attribute(ua.AttributeIds.ValueRank)
159 1
        return res.Value.Value
160 1
161
    def set_value(self, value, varianttype=None):
162 1
        """
163 1
        Set value of a node. Only variables(properties) have values.
164 1
        An exception will be generated for other node types.
165 1
        value argument is either:
166
        * a python built-in type, converted to opc-ua
167 1
        optionnaly using the variantype argument.
168 1
        * a ua.Variant, varianttype is then ignored
169 1
        * a ua.DataValue, you then have full control over data send to server
170 1
        """
171
        datavalue = None
172 1
        if isinstance(value, ua.DataValue):
173
            datavalue = value
174
        elif isinstance(value, ua.Variant):
175
            datavalue = ua.DataValue(value)
176
        else:
177
            datavalue = ua.DataValue(ua.Variant(value, varianttype))
178
        self.set_attribute(ua.AttributeIds.Value, datavalue)
179 1
180
    set_data_value = set_value
181
182
    def set_writable(self, writable=True):
183
        """
184
        Set node as writable by clients.
185 1
        A node is always writable on server side.
186 1
        """
187 1
        if writable:
188 1
            self.set_attr_bit(ua.AttributeIds.AccessLevel, ua.AccessLevel.CurrentWrite)
189 1
            self.set_attr_bit(ua.AttributeIds.UserAccessLevel, ua.AccessLevel.CurrentWrite)
190 1
        else:
191 1
            self.unset_attr_bit(ua.AttributeIds.AccessLevel, ua.AccessLevel.CurrentWrite)
192 1
            self.unset_attr_bit(ua.AttributeIds.UserAccessLevel, ua.AccessLevel.CurrentWrite)
193
194 1
    def set_attr_bit(self, attr, bit):
195
        val = self.get_attribute(attr)
196
        val.Value.Value = ua.set_bit(val.Value.Value, bit)
197
        self.set_attribute(attr, val)
198
199 1
    def unset_attr_bit(self, attr, bit):
200 1
        val = self.get_attribute(attr)
201 1
        val.Value.Value = ua.unset_bit(val.Value.Value, bit)
202 1
        self.set_attribute(attr, val)
203 1
204 1
    def set_read_only(self):
205 1
        """
206 1
        Set a node as read-only for clients.
207
        A node is always writable on server side.
208 1
        """
209
        return self.set_writable(False)
210
211
    def set_attribute(self, attributeid, datavalue):
212
        """
213
        Set an attribute of a node
214
        attributeid is a member of ua.AttributeIds
215
        datavalue is a ua.DataValue object
216
        """
217
        attr = ua.WriteValue()
218
        attr.NodeId = self.nodeid
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        attr.AttributeId = attributeid
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        attr.Value = datavalue
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        params = ua.WriteParameters()
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        params.NodesToWrite = [attr]
223 1
        result = self.server.write(params)
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        result[0].check()
225
226
    def get_attribute(self, attr):
227
        """
228
        Read one attribute of a node
229
        result code from server is checked and an exception is raised in case of error
230
        """
231
        rv = ua.ReadValueId()
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        rv.NodeId = self.nodeid
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        rv.AttributeId = attr
234
        params = ua.ReadParameters()
235
        params.NodesToRead.append(rv)
236
        result = self.server.read(params)
237
        result[0].StatusCode.check()
238
        return result[0]
239
240
    def get_attributes(self, attrs):
241
        """
242
        Read several attributes of a node
243
        list of DataValue is returned
244
        """
245 1
        params = ua.ReadParameters()
246
        for attr in attrs:
247 1
            rv = ua.ReadValueId()
248
            rv.NodeId = self.nodeid
249
            rv.AttributeId = attr
250
            params.NodesToRead.append(rv)
251
252 1
        results = self.server.read(params)
253
        return results
254 1
255
    def get_children(self, refs=ua.ObjectIds.HierarchicalReferences, nodeclassmask=ua.NodeClass.Unspecified):
256
        """
257 1
        Get all children of a node. By default hierarchical references and all node classes are returned.
258
        Other reference types may be given:
259
        References = 31
260
        NonHierarchicalReferences = 32
261
        HierarchicalReferences = 33
262
        HasChild = 34
263
        Organizes = 35
264
        HasEventSource = 36
265
        HasModellingRule = 37
266 1
        HasEncoding = 38
267 1
        HasDescription = 39
268 1
        HasTypeDefinition = 40
269 1
        GeneratesEvent = 41
270 1
        Aggregates = 44
271 1
        HasSubtype = 45
272
        HasProperty = 46
273 1
        HasComponent = 47
274 1
        HasNotifier = 48
275 1
        HasOrderedComponent = 49
276 1
        """
277 1
        return self.get_referenced_nodes(refs, ua.BrowseDirection.Forward, nodeclassmask)
278 1
279
    def get_properties(self):
280 1
        """
281
        return properties of node.
282
        properties are child nodes with a reference of type HasProperty and a NodeClass of Variable
283
        """
284
        return self.get_children(refs=ua.ObjectIds.HasProperty, nodeclassmask=ua.NodeClass.Variable)
285
286 1
    def get_children_descriptions(self, refs=ua.ObjectIds.HierarchicalReferences, nodeclassmask=ua.NodeClass.Unspecified, includesubtypes=True):
287 1
        return self.get_references(refs, ua.BrowseDirection.Forward, nodeclassmask, includesubtypes)
288 1
289 1
    def get_references(self, refs=ua.ObjectIds.References, direction=ua.BrowseDirection.Both, nodeclassmask=ua.NodeClass.Unspecified, includesubtypes=True):
290 1
        """
291 1
        returns references of the node based on specific filter defined with:
292
293 1
        refs = ObjectId of the Reference
294
        direction = Browse direction for references
295
        nodeclassmask = filter nodes based on specific class
296
        includesubtypes = If true subtypes of the reference (ref) are also included
297 1
        """
298 1
        desc = ua.BrowseDescription()
299 1
        desc.BrowseDirection = direction
300 1
        desc.ReferenceTypeId = ua.TwoByteNodeId(refs)
301
        desc.IncludeSubtypes = includesubtypes
302 1
        desc.NodeClassMask = nodeclassmask
303
        desc.ResultMask = ua.BrowseResultMask.All
304
305
        desc.NodeId = self.nodeid
306 1
        params = ua.BrowseParameters()
307
        params.View.Timestamp = ua.win_epoch_to_datetime(0)
308 1
        params.NodesToBrowse.append(desc)
309
        results = self.server.browse(params)
310 1
        return results[0].References
311
312
    def get_referenced_nodes(self, refs=ua.ObjectIds.References, direction=ua.BrowseDirection.Both, nodeclassmask=ua.NodeClass.Unspecified, includesubtypes=True):
313
        """
314
        returns referenced nodes based on specific filter
315
        Paramters are the same as for get_references
316
317
        """
318
        references = self.get_references(refs, direction, nodeclassmask, includesubtypes)
319 1
        nodes = []
320 1
        for desc in references:
321 1
            node = Node(self.server, desc.NodeId)
322 1
            nodes.append(node)
323 1
        return nodes
324 1
325 1
    def get_type_definition(self):
326 1
        """
327 1
        returns type definition of the node.
328
        """
329 1
        references = self.get_references(refs=ua.ObjectIds.HasTypeDefinition, direction=ua.BrowseDirection.Forward)
330
        if len(references) == 0:
331 1
            return ua.ObjectIds.BaseObjectType
332 1
        return references[0].NodeId.Identifier
333 1
334 1
    def get_parent(self):
335 1
        """
336 1
        returns parent of the node.
337 1
        """
338 1
        refs = self.get_references(refs=ua.ObjectIds.HierarchicalReferences, direction=ua.BrowseDirection.Inverse)
339
340
        return Node(self.server, refs[0].NodeId)
341 1
342 1
    def get_child(self, path):
343 1
        """
344
        get a child specified by its path from this node.
345 1
        A path might be:
346
        * a string representing a qualified name.
347
        * a qualified name
348
        * a list of string
349
        * a list of qualified names
350
        """
351
        if type(path) not in (list, tuple):
352 1
            path = [path]
353 1
        rpath = self._make_relative_path(path)
354 1
        bpath = ua.BrowsePath()
355 1
        bpath.StartingNode = self.nodeid
356
        bpath.RelativePath = rpath
357 1
        result = self.server.translate_browsepaths_to_nodeids([bpath])
358 1
        result = result[0]
359 1
        result.StatusCode.check()
360
        # FIXME: seems this method may return several nodes
361 1
        return Node(self.server, result.Targets[0].TargetId)
362 1
363 1
    def _make_relative_path(self, path):
364 1
        rpath = ua.RelativePath()
365 1
        for item in path:
366
            el = ua.RelativePathElement()
367 1
            el.ReferenceTypeId = ua.TwoByteNodeId(ua.ObjectIds.HierarchicalReferences)
368
            el.IsInverse = False
369
            el.IncludeSubtypes = True
370
            if isinstance(item, ua.QualifiedName):
371
                el.TargetName = item
372 1
            else:
373 1
                el.TargetName = ua.QualifiedName.from_string(item)
374 1
            rpath.Elements.append(el)
375
        return rpath
376 1
377 1
    def read_raw_history(self, starttime=None, endtime=None, numvalues=0):
378 1
        """
379 1
        Read raw history of a node
380 1
        result code from server is checked and an exception is raised in case of error
381 1
        If numvalues is > 0 and number of events in period is > numvalues
382 1
        then result will be truncated
383
        """
384 1
        details = ua.ReadRawModifiedDetails()
385
        details.IsReadModified = False
386
        if starttime:
387
            details.StartTime = starttime
388
        else:
389
            details.StartTime = ua.DateTimeMinValue
390
        if endtime:
391
            details.EndTime = endtime
392
        else:
393
            details.EndTime = ua.DateTimeMinValue
394
        details.NumValuesPerNode = numvalues
395
        details.ReturnBounds = True
396 1
        result = self.history_read(details)
397 1
        return result.HistoryData.DataValues
398 1
399
    def history_read(self, details):
400 1
        """
401 1
        Read raw history of a node, low-level function
402 1
        result code from server is checked and an exception is raised in case of error
403
        """
404 1
        valueid = ua.HistoryReadValueId()
405 1
        valueid.NodeId = self.nodeid
406
        valueid.IndexRange = ''
407 1
408
        params = ua.HistoryReadParameters()
409 1
        params.HistoryReadDetails = details
410 1
        params.TimestampsToReturn = ua.TimestampsToReturn.Both
411
        params.ReleaseContinuationPoints = False
412 1
        params.NodesToRead.append(valueid)
413
        result = self.server.history_read(params)[0]
414
        return result
415
416
    def read_event_history(self, starttime=None, endtime=None, numvalues=0, evtypes=ua.ObjectIds.BaseEventType):
417 1
        """
418 1
        Read event history of a source node 
419 1
        result code from server is checked and an exception is raised in case of error
420
        If numvalues is > 0 and number of events in period is > numvalues
421 1
        then result will be truncated
422 1
        """
423 1
424 1
        details = ua.ReadEventDetails()
425 1
        if starttime:
426 1
            details.StartTime = starttime
427 1
        else:
428
            details.StartTime = ua.DateTimeMinValue
429
        if endtime:
430
            details.EndTime = endtime
431
        else:
432
            details.EndTime = ua.DateTimeMinValue
433
        details.NumValuesPerNode = numvalues
434 1
435 1
        if not isinstance(evtypes, (list, tuple)):
436 1
            evtypes = [evtypes]
437
438 1
        evtypes = [Node(self.server, evtype) for evtype in evtypes]
439 1
440 1
        evfilter = events.get_filter_from_event_type(evtypes)
441
        details.Filter = evfilter
442 1
443 1
        result = self.history_read_events(details)
444 1
        event_res = []
445
        for res in result.HistoryData.Events:
446 1
            event_res.append(events.Event.from_event_fields(evfilter.SelectClauses, res.EventFields))
447 1
        return event_res
448 1
449
    def history_read_events(self, details):
450 1
        """
451 1
        Read event history of a node, low-level function
452 1
        result code from server is checked and an exception is raised in case of error
453
        """
454 1
        valueid = ua.HistoryReadValueId()
455 1
        valueid.NodeId = self.nodeid
456 1
        valueid.IndexRange = ''
457
458 1
        params = ua.HistoryReadParameters()
459 1
        params.HistoryReadDetails = details
460 1
        params.TimestampsToReturn = ua.TimestampsToReturn.Both
461
        params.ReleaseContinuationPoints = False
462
        params.NodesToRead.append(valueid)
463
        result = self.server.history_read(params)[0]
464
        return result
465
466
    # Hack for convenience methods
467
    # local import is ugly but necessary for python2 support
468
    # feel fri to propose something better but I want to split all those
469
    # create methods from Node
470
471
    def add_folder(*args, **kwargs):
472
        from opcua.common import manage_nodes
473
        return manage_nodes.create_folder(*args, **kwargs)
474
475
    def add_object(*args, **kwargs):
476
        from opcua.common import manage_nodes
477
        return manage_nodes.create_object(*args, **kwargs)
478
479
    def add_variable(*args, **kwargs):
480
        from opcua.common import manage_nodes
481
        return manage_nodes.create_variable(*args, **kwargs)
482
483
    def add_property(*args, **kwargs):
484
        from opcua.common import manage_nodes
485
        return manage_nodes.create_property(*args, **kwargs)
486
487
    def add_method(*args, **kwargs):
488
        from opcua.common import manage_nodes
489
        return manage_nodes.create_method(*args, **kwargs)
490
491
    def add_subtype(*args, **kwargs):
492
        from opcua.common import manage_nodes
493
        return manage_nodes.create_subtype(*args, **kwargs)
494
495
    def call_method(*args, **kwargs):
496
        from opcua.common import methods
497
        return methods.call_method(*args, **kwargs)
498