"""
implement ua datatypes
"""
import logging
from enum import Enum, IntEnum
from calendar import timegm
import pytz
import sys
import os
import uuid
import re
import itertools
from datetime import datetime, timedelta, MAXYEAR, tzinfo
from opcua.ua import status_codes
from opcua.ua import ObjectIds
from opcua.ua.uaerrors import UaError
from opcua.ua.uaerrors import UaStatusCodeError
from opcua.ua.uaerrors import UaStringParsingError
logger = logging.getLogger(__name__)
if sys.version_info.major > 2:
unicode = str
EPOCH_AS_FILETIME = 116444736000000000 # January 1, 1970 as MS file time
HUNDREDS_OF_NANOSECONDS = 10000000
FILETIME_EPOCH_AS_DATETIME = datetime(1601, 1, 1)
# method copied from David Buxton <david@gasmark6.com> sample code
[docs]def datetime_to_win_epoch(dt):
if (dt.tzinfo is None) or (dt.tzinfo.utcoffset(dt) is None):
dt = dt.replace(tzinfo=pytz.utc)
else:
dt = dt.astimezone(tz=pytz.utc)
ft = EPOCH_AS_FILETIME + (timegm(dt.timetuple()) * HUNDREDS_OF_NANOSECONDS)
return ft + (dt.microsecond * 10)
[docs]def get_win_epoch():
return win_epoch_to_datetime(0)
[docs]def win_epoch_to_datetime(epch):
try:
return FILETIME_EPOCH_AS_DATETIME + timedelta(microseconds=epch // 10)
except OverflowError:
# FILETIMEs after 31 Dec 9999 can't be converted to datetime
logger.warning("datetime overflow: %s", epch)
return datetime(MAXYEAR, 12, 31, 23, 59, 59, 999999)
class _FrozenClass(object):
"""
Make it impossible to add members to a class.
Not pythonic at all but we found out it prevents many many
bugs in use of protocol structures
"""
_freeze = False
def __setattr__(self, key, value):
if self._freeze and not hasattr(self, key):
raise TypeError("Error adding member '{0}' to class '{1}', class is frozen, members are {2}".format(
key, self.__class__.__name__, self.__dict__.keys()))
object.__setattr__(self, key, value)
if "PYOPCUA_TYPO_CHECK" in os.environ:
# typo check is cpu consuming, but it will make debug easy.
# set PYOPCUA_TYPO_CHECK will make all uatype classes inherit from _FrozenClass
FrozenClass = _FrozenClass
else:
FrozenClass = object
[docs]class ValueRank(IntEnum):
"""
Defines dimensions of a variable.
This enum does not support all cases since ValueRank support any n>0
but since it is an IntEnum it can be replace by a normal int
"""
ScalarOrOneDimension = -3
Any = -2
Scalar = -1
OneOrMoreDimensions = 0
OneDimension = 1
# the next names are not in spec but so common we express them here
TwoDimensions = 2
ThreeDimensions = 3
FourDimensions = 4
class _MaskEnum(IntEnum):
@classmethod
def parse_bitfield(cls, the_int):
""" Take an integer and interpret it as a set of enum values. """
if not isinstance(the_int, int):
raise ValueError("Argument should be an int, we received {} fo type {}".format(the_int, type(the_int)))
return {cls(b) for b in cls._bits(the_int)}
@classmethod
def to_bitfield(cls, collection):
""" Takes some enum values and creates an integer from them. """
# make sure all elements are of the correct type (use itertools.tee in case we get passed an
# iterator)
iter1, iter2 = itertools.tee(iter(collection))
assert all(isinstance(x, cls) for x in iter1)
return sum(x.mask for x in iter2)
@property
def mask(self):
return 1 << self.value
@staticmethod
def _bits(n):
""" Iterate over the bits in n.
e.g. bits(44) yields at 2, 3, 5
"""
assert n >= 0 # avoid infinite recursion
pos = 0
while n:
if n & 0x1:
yield pos
n = n // 2
pos += 1
[docs]class AccessLevel(_MaskEnum):
"""
Bit index to indicate what the access level is.
Spec Part 3, appears multiple times, e.g. paragraph 5.6.2 Variable NodeClass
"""
CurrentRead = 0
CurrentWrite = 1
HistoryRead = 2
HistoryWrite = 3
SemanticChange = 4
StatusWrite = 5
TimestampWrite = 6
[docs]class WriteMask(_MaskEnum):
"""
Bit index to indicate which attribute of a node is writable
Spec Part 3, Paragraph 5.2.7 WriteMask
"""
AccessLevel = 0
ArrayDimensions = 1
BrowseName = 2
ContainsNoLoops = 3
DataType = 4
Description = 5
DisplayName = 6
EventNotifier = 7
Executable = 8
Historizing = 9
InverseName = 10
IsAbstract = 11
MinimumSamplingInterval = 12
NodeClass = 13
NodeId = 14
Symmetric = 15
UserAccessLevel = 16
UserExecutable = 17
UserWriteMask = 18
ValueRank = 19
WriteMask = 20
ValueForVariableType = 21
[docs]class EventNotifier(_MaskEnum):
"""
Bit index to indicate how a node can be used for events.
Spec Part 3, appears multiple times, e.g. Paragraph 5.4 View NodeClass
"""
SubscribeToEvents = 0
# Reserved = 1
HistoryRead = 2
HistoryWrite = 3
[docs]class StatusCode(FrozenClass):
"""
:ivar value:
:vartype value: int
:ivar name:
:vartype name: string
:ivar doc:
:vartype doc: string
"""
ua_types = [("value", "UInt32")]
def __init__(self, value=0):
if isinstance(value, str):
self.value = getattr(status_codes.StatusCodes, value)
else:
self.value = value
self._freeze = True
[docs] def check(self):
"""
Raises an exception if the status code is anything else than 0 (good).
Use the is_good() method if you do not want an exception.
"""
if not self.is_good():
raise UaStatusCodeError(self.value)
[docs] def is_good(self):
"""
return True if status is Good.
"""
mask = 3 << 30
if mask & self.value:
return False
else:
return True
@property
def name(self):
name, _ = status_codes.get_name_and_doc(self.value)
return name
@property
def doc(self):
_, doc = status_codes.get_name_and_doc(self.value)
return doc
def __str__(self):
return 'StatusCode({0})'.format(self.name)
__repr__ = __str__
def __eq__(self, other):
return self.value == other.value
def __ne__(self, other):
return not self.__eq__(other)
[docs]class NodeIdType(IntEnum):
TwoByte = 0
FourByte = 1
Numeric = 2
String = 3
Guid = 4
ByteString = 5
[docs]class NodeId(object):
"""
NodeId Object
Args:
identifier: The identifier might be an int, a string, bytes or a Guid
namespaceidx(int): The index of the namespace
nodeidtype(NodeIdType): The type of the nodeid if it cannor be guess or you want something special like twobyte nodeid or fourbytenodeid
:ivar Identifier:
:vartype Identifier: NodeId
:ivar NamespaceIndex:
:vartype NamespaceIndex: Int
:ivar NamespaceUri:
:vartype NamespaceUri: String
:ivar ServerIndex:
:vartype ServerIndex: Int
"""
def __init__(self, identifier=None, namespaceidx=0, nodeidtype=None):
self.Identifier = identifier
self.NamespaceIndex = namespaceidx
self.NodeIdType = nodeidtype
self.NamespaceUri = ""
self.ServerIndex = 0
self._freeze = True
if self.Identifier is None:
self.Identifier = 0
if namespaceidx == 0:
self.NodeIdType = NodeIdType.TwoByte
else: # TwoByte NodeId does not encode namespace.
self.NodeIdType = NodeIdType.Numeric
return
if self.NodeIdType is None:
if isinstance(self.Identifier, int):
self.NodeIdType = NodeIdType.Numeric
elif isinstance(self.Identifier, str):
self.NodeIdType = NodeIdType.String
elif isinstance(self.Identifier, bytes):
self.NodeIdType = NodeIdType.ByteString
elif isinstance(self.Identifier, uuid.UUID):
self.NodeIdType = NodeIdType.Guid
else:
raise UaError("NodeId: Could not guess type of NodeId, set NodeIdType")
def __eq__(self, node):
return isinstance(node, NodeId) and self.NamespaceIndex == node.NamespaceIndex and self.Identifier == node.Identifier
def __ne__(self, other):
return not self.__eq__(other)
def __hash__(self):
return hash((self.NamespaceIndex, self.Identifier))
def __lt__(self, other):
if not isinstance(other, NodeId):
raise AttributeError("Can only compare to NodeId")
return (self.NodeIdType, self.NamespaceIndex, self.Identifier) < (other.NodeIdType, other.NamespaceIndex, other.Identifier)
[docs] def is_null(self):
if self.NamespaceIndex != 0:
return False
return self.has_null_identifier()
[docs] def has_null_identifier(self):
if not self.Identifier:
return True
if self.NodeIdType == NodeIdType.Guid and re.match(b'\x00+', self.Identifier.bytes):
return True
return False
[docs] @staticmethod
def from_string(string):
try:
return NodeId._from_string(string)
except ValueError as ex:
raise UaStringParsingError("Error parsing string {0}".format(string), ex)
@staticmethod
def _from_string(string):
l = string.split(";")
identifier = None
namespace = 0
ntype = None
srv = None
nsu = None
for el in l:
if not el:
continue
k, v = el.split("=", 1)
k = k.strip()
v = v.strip()
if k == "ns":
namespace = int(v)
elif k == "i":
ntype = NodeIdType.Numeric
identifier = int(v)
elif k == "s":
ntype = NodeIdType.String
identifier = v
elif k == "g":
ntype = NodeIdType.Guid
identifier = v
elif k == "b":
ntype = NodeIdType.ByteString
identifier = v
elif k == "srv":
srv = v
elif k == "nsu":
nsu = v
if identifier is None:
raise UaStringParsingError("Could not find identifier in string: " + string)
nodeid = NodeId(identifier, namespace, ntype)
nodeid.NamespaceUri = nsu
nodeid.ServerIndex = srv
return nodeid
[docs] def to_string(self):
string = []
if self.NamespaceIndex != 0:
string.append("ns={0}".format(self.NamespaceIndex))
ntype = None
if self.NodeIdType == NodeIdType.Numeric:
ntype = "i"
elif self.NodeIdType == NodeIdType.String:
ntype = "s"
elif self.NodeIdType == NodeIdType.TwoByte:
ntype = "i"
elif self.NodeIdType == NodeIdType.FourByte:
ntype = "i"
elif self.NodeIdType == NodeIdType.Guid:
ntype = "g"
elif self.NodeIdType == NodeIdType.ByteString:
ntype = "b"
string.append("{0}={1}".format(ntype, self.Identifier))
if self.ServerIndex:
string.append("srv={}".format(self.ServerIndex))
if self.NamespaceUri:
string.append("nsu={0}".format(self.NamespaceUri))
return ";".join(string)
def __str__(self):
return "{0}NodeId({1})".format(self.NodeIdType.name, self.to_string())
__repr__ = __str__
[docs] def to_binary(self):
import opcua
return opcua.ua.ua_binary.nodeid_to_binary(self)
[docs]class TwoByteNodeId(NodeId):
def __init__(self, identifier):
NodeId.__init__(self, identifier, 0, NodeIdType.TwoByte)
[docs]class FourByteNodeId(NodeId):
def __init__(self, identifier, namespace=0):
NodeId.__init__(self, identifier, namespace, NodeIdType.FourByte)
[docs]class NumericNodeId(NodeId):
def __init__(self, identifier, namespace=0):
NodeId.__init__(self, identifier, namespace, NodeIdType.Numeric)
[docs]class ByteStringNodeId(NodeId):
def __init__(self, identifier, namespace=0):
NodeId.__init__(self, identifier, namespace, NodeIdType.ByteString)
[docs]class GuidNodeId(NodeId):
def __init__(self, identifier, namespace=0):
NodeId.__init__(self, identifier, namespace, NodeIdType.Guid)
[docs]class StringNodeId(NodeId):
def __init__(self, identifier, namespace=0):
NodeId.__init__(self, identifier, namespace, NodeIdType.String)
ExpandedNodeId = NodeId
[docs]class QualifiedName(FrozenClass):
"""
A string qualified with a namespace index.
"""
ua_types = [
('NamespaceIndex', 'UInt16'),
('Name', 'String'),
]
def __init__(self, name=None, namespaceidx=0):
if not isinstance(namespaceidx, int):
raise UaError("namespaceidx must be an int")
self.NamespaceIndex = namespaceidx
self.Name = name
self._freeze = True
[docs] def to_string(self):
return "{0}:{1}".format(self.NamespaceIndex, self.Name)
[docs] @staticmethod
def from_string(string):
if ":" in string:
try:
idx, name = string.split(":", 1)
idx = int(idx)
except (TypeError, ValueError) as ex:
raise UaStringParsingError("Error parsing string {0}".format(string), ex)
else:
idx = 0
name = string
return QualifiedName(name, idx)
def __eq__(self, bname):
return isinstance(bname,
QualifiedName) and self.Name == bname.Name and self.NamespaceIndex == bname.NamespaceIndex
def __ne__(self, other):
return not self.__eq__(other)
def __lt__(self, other):
if not isinstance(other, QualifiedName):
raise TypeError("Cannot compare QualifiedName and {0}".format(other))
if self.NamespaceIndex == other.NamespaceIndex:
return self.Name < other.Name
else:
return self.NamespaceIndex < other.NamespaceIndex
def __str__(self):
return 'QualifiedName({0}:{1})'.format(self.NamespaceIndex, self.Name)
__repr__ = __str__
[docs]class LocalizedText(FrozenClass):
"""
A string qualified with a namespace index.
"""
ua_switches = {
'Locale': ('Encoding', 0),
'Text': ('Encoding', 1),
}
ua_types = (
('Encoding', 'Byte'),
('Locale', 'String'),
('Text', 'String'), )
def __init__(self, text=None, locale=None):
self.Encoding = 0
self._text = None
self._locale = None
if text:
self.Text = text
if locale:
self.Locale = locale
self._freeze = True
@property
def Text(self):
return self._text
@property
def Locale(self):
return self._locale
@Text.setter
def Text(self, text):
if isinstance(text, str):
pass
elif isinstance(text, bytes):
text = text.decode()
else:
raise ValueError("A LocalizedText object takes a string as argument, not a {}, {}".format(type(text), text))
self._text = text
if self._text:
self.Encoding |= (1 << 1)
@Locale.setter
def Locale(self, locale):
if not isinstance(locale, str):
raise ValueError("A LocalizedText object takes a string as argument, not a {}, {}".format({type(locale)}, {locale}))
self._locale = locale
if self._locale:
self.Encoding |= (1)
[docs] def to_string(self):
if self.Text is None:
return ""
if self.Locale is None:
return self.Text
return self.__str__()
[docs] @staticmethod
def from_string(string):
m = re.match(r"^LocalizedText\(Encoding:(.*), Locale:(.*), Text:(.*)\)$", string)
if m:
text = m.group(3) if m.group(3) != str(None) else None
locale = m.group(2) if m.group(2) != str(None) else None
return LocalizedText(text=text, locale=locale)
else:
return LocalizedText(string)
def __str__(self):
return 'LocalizedText(' + 'Encoding:' + str(self.Encoding) + ', ' + \
'Locale:' + str(self.Locale) + ', ' + \
'Text:' + str(self.Text) +')'
__repr__ = __str__
def __eq__(self, other):
if isinstance(other, LocalizedText) and self.Locale == other.Locale and self.Text == other.Text:
return True
return False
def __ne__(self, other):
return not self.__eq__(other)
[docs]class ExtensionObject(FrozenClass):
"""
Any UA object packed as an ExtensionObject
:ivar TypeId:
:vartype TypeId: NodeId
:ivar Body:
:vartype Body: bytes
"""
ua_switches = {
'Body': ('Encoding', 0),
}
ua_types = (
("TypeId", "NodeId"),
("Encoding", "Byte"),
("Body", "ByteString"),
)
def __init__(self):
self.TypeId = NodeId()
self.Encoding = 0
self.Body = None
self._freeze = True
def __bool__(self):
return self.Body is not None
__nonzero__ = __bool__ # Python2 compatibilty
def __str__(self):
size = len(self.Body) if self.Body is not None else None
return 'ExtensionObject(' + 'TypeId:' + str(self.TypeId) + ', ' + \
'Encoding:' + str(self.Encoding) + ', ' + str(size) + ' bytes)'
__repr__ = __str__
[docs]class VariantType(Enum):
"""
The possible types of a variant.
:ivar Null:
:ivar Boolean:
:ivar SByte:
:ivar Byte:
:ivar Int16:
:ivar UInt16:
:ivar Int32:
:ivar UInt32:
:ivar Int64:
:ivar UInt64:
:ivar Float:
:ivar Double:
:ivar String:
:ivar DateTime:
:ivar Guid:
:ivar ByteString:
:ivar XmlElement:
:ivar NodeId:
:ivar ExpandedNodeId:
:ivar StatusCode:
:ivar QualifiedName:
:ivar LocalizedText:
:ivar ExtensionObject:
:ivar DataValue:
:ivar Variant:
:ivar DiagnosticInfo:
"""
Null = 0
Boolean = 1
SByte = 2
Byte = 3
Int16 = 4
UInt16 = 5
Int32 = 6
UInt32 = 7
Int64 = 8
UInt64 = 9
Float = 10
Double = 11
String = 12
DateTime = 13
Guid = 14
ByteString = 15
XmlElement = 16
NodeId = 17
ExpandedNodeId = 18
StatusCode = 19
QualifiedName = 20
LocalizedText = 21
ExtensionObject = 22
DataValue = 23
Variant = 24
DiagnosticInfo = 25
[docs]class VariantTypeCustom(object):
"""
Looks like sometime we get variant with other values than those
defined in VariantType.
FIXME: We should not need this class, as far as I iunderstand the spec
variants can only be of VariantType
"""
def __init__(self, val):
self.name = "Custom"
self.value = val
if self.value > 0b00111111:
raise UaError(
"Cannot create VariantType. VariantType must be {0} > x > {1}, received {2}".format(0b111111, 25, val))
def __str__(self):
return "VariantType.Custom:{0}".format(self.value)
__repr__ = __str__
def __eq__(self, other):
return self.value == other.value
[docs]class Variant(FrozenClass):
"""
Create an OPC-UA Variant object.
if no argument a Null Variant is created.
if not variant type is given, attemps to guess type from python type
if a variant is given as value, the new objects becomes a copy of the argument
:ivar Value:
:vartype Value: Any supported type
:ivar VariantType:
:vartype VariantType: VariantType
:ivar Dimension:
:vartype Dimensions: The length of each dimensions. Usually guessed from value.
:ivar is_array:
:vartype is_array: If the variant is an array. Usually guessed from value.
"""
def __init__(self, value=None, varianttype=None, dimensions=None, is_array=None):
self._freeze = False # defers validation until ready.
# Value, VariantType
self._value = None
self._variantType = None
if isinstance(value, Variant):
self.Value = value.Value
self.VariantType = value.VariantType
else:
self.Value = value
self.VariantType = varianttype
# Dimensions
self.Dimensions = dimensions
if dimensions is None and isinstance(self.Value, (list, tuple)):
dims = get_shape(self.Value)
if len(dims) > 1:
self.Dimensions = dims
# is_array
if is_array is not None:
self.is_array = bool(is_array)
else:
self.is_array = isinstance(self.Value, (list, tuple))
# Validation check
self._freeze = True
self._validate()
@property
def Value(self):
return self._value
@Value.setter
def Value(self, value):
if not (self._value is None or isinstance(value, type(self._value))):
logger.warning("Datatype changed from {} to {} in Variant {}.".format(type(self._value), type(value), self))
self._value = value
self._validate()
@property
def VariantType(self):
return self._variantType
@VariantType.setter
def VariantType(self, variantType):
if variantType is not None:
self._variantType = variantType
else:
self._variantType = self._guess_type(self.Value)
self._validate()
def _validate(self):
if self._freeze is False:
return
elif isinstance(self._value, int) and self.VariantType in (VariantType.Float, VariantType.Double):
self._value = float(self._value)
elif self._value is None and not self.is_array and \
self.VariantType not in (VariantType.Null, VariantType.String, VariantType.DateTime):
raise UaError("Non array Variant of type {0} cannot have value None".format(self.VariantType))
def __eq__(self, other):
if isinstance(other, Variant) and self.VariantType == other.VariantType and self.Value == other.Value:
return True
return False
def __ne__(self, other):
return not self.__eq__(other)
def _guess_type(self, val):
if isinstance(val, (list, tuple)):
error_val = val
while val and isinstance(val[0], (list, tuple)):
val = val[0]
types = {type(el) for el in val}
if len(types) == 0:
raise UaError("List of zero length. Could not guess UA type of variable {0}".format(error_val))
elif types == set([int, float]):
logger.debug(
"Variable {0} has ints and floats. UA type will be {1}".format(error_val, VariantType.Double)
)
val = float()
elif len(types) > 1:
raise UaError("List of multiple types. Could not guess UA type of variable {0}".format(error_val))
else:
val = val[0]
if val is None:
return VariantType.Null
elif isinstance(val, bool):
return VariantType.Boolean
elif isinstance(val, float):
return VariantType.Double
elif isinstance(val, IntEnum):
return VariantType.Int32
elif isinstance(val, int):
return VariantType.Int64
elif isinstance(val, (str, unicode)):
return VariantType.String
elif isinstance(val, bytes):
return VariantType.ByteString
elif isinstance(val, datetime):
return VariantType.DateTime
elif isinstance(val, uuid.UUID):
return VariantType.Guid
else:
if isinstance(val, object):
try:
return getattr(VariantType, val.__class__.__name__)
except AttributeError:
return VariantType.ExtensionObject
else:
raise UaError("Could not guess UA type of {0} with type {1}, specify UA type".format(val, type(val)))
def __str__(self):
return "Variant(val:{0!s},type:{1})".format(self.Value, self.VariantType)
__repr__ = __str__
def _split_list(l, n):
n = max(1, n)
return [l[i:i + n] for i in range(0, len(l), n)]
[docs]def flatten_and_get_shape(mylist):
dims = []
dims.append(len(mylist))
while isinstance(mylist[0], (list, tuple)):
dims.append(len(mylist[0]))
mylist = [item for sublist in mylist for item in sublist]
if len(mylist) == 0:
break
return mylist, dims
[docs]def flatten(mylist):
if mylist is None:
return None
elif len(mylist) == 0:
return mylist
while isinstance(mylist[0], (list, tuple)):
mylist = [item for sublist in mylist for item in sublist]
if len(mylist) == 0:
break
return mylist
[docs]def get_shape(mylist):
dims = []
while isinstance(mylist, (list, tuple)):
dims.append(len(mylist))
if len(mylist) == 0:
break
mylist = mylist[0]
return dims
[docs]class DataValue(FrozenClass):
"""
A value with an associated timestamp, and quality.
Automatically generated from xml , copied and modified here to fix errors in xml spec
:ivar Value:
:vartype Value: Variant
:ivar StatusCode:
:vartype StatusCode: StatusCode
:ivar SourceTimestamp:
:vartype SourceTimestamp: datetime
:ivar SourcePicoSeconds:
:vartype SourcePicoSeconds: int
:ivar ServerTimestamp:
:vartype ServerTimestamp: datetime
:ivar ServerPicoseconds:
:vartype ServerPicoseconds: int
"""
ua_switches = {
'Value': ('Encoding', 0),
'StatusCode': ('Encoding', 1),
'SourceTimestamp': ('Encoding', 2),
'ServerTimestamp': ('Encoding', 3),
'SourcePicoseconds': ('Encoding', 4),
'ServerPicoseconds': ('Encoding', 5),
}
ua_types = (
('Encoding', 'Byte'),
('Value', 'Variant'),
('StatusCode', 'StatusCode'),
('SourceTimestamp', 'DateTime'),
('SourcePicoseconds', 'UInt16'),
('ServerTimestamp', 'DateTime'),
('ServerPicoseconds', 'UInt16'),
)
def __init__(self, variant=None, status=None, sourceTimestamp=None, sourcePicoseconds=None, serverTimestamp=None, serverPicoseconds=None):
self.Encoding = 0
if not isinstance(variant, Variant):
variant = Variant(variant)
self.Value = variant
if status is None:
self.StatusCode = StatusCode()
else:
self.StatusCode = status
self.SourceTimestamp = sourceTimestamp
self.SourcePicoseconds = sourcePicoseconds
self.ServerTimestamp = serverTimestamp
self.ServerPicoseconds = serverPicoseconds
self._freeze = True
def __str__(self):
s = 'DataValue(Value:{0}'.format(self.Value)
if self.StatusCode is not None:
s += ', StatusCode:{0}'.format(self.StatusCode)
if self.SourceTimestamp is not None:
s += ', SourceTimestamp:{0}'.format(self.SourceTimestamp)
if self.ServerTimestamp is not None:
s += ', ServerTimestamp:{0}'.format(self.ServerTimestamp)
if self.SourcePicoseconds is not None:
s += ', SourcePicoseconds:{0}'.format(self.SourcePicoseconds)
if self.ServerPicoseconds is not None:
s += ', ServerPicoseconds:{0}'.format(self.ServerPicoseconds)
s += ')'
return s
__repr__ = __str__
[docs]def datatype_to_varianttype(int_type):
"""
Takes a NodeId or int and return a VariantType
This is only supported if int_type < 63 due to VariantType encoding
At low level we do not have access to address space thus decoding is limited
a better version of this method can be find in ua_utils.py
"""
if isinstance(int_type, NodeId):
int_type = int_type.Identifier
if int_type <= 25:
return VariantType(int_type)
else:
return VariantTypeCustom(int_type)
[docs]def get_default_value(vtype):
"""
Given a variant type return default value for this type
"""
if vtype == VariantType.Null:
return None
elif vtype == VariantType.Boolean:
return False
elif vtype in (VariantType.SByte, VariantType.Byte):
return 0
elif vtype == VariantType.ByteString:
return b""
elif 4 <= vtype.value <= 9:
return 0
elif vtype in (VariantType.Float, VariantType.Double):
return 0.0
elif vtype == VariantType.String:
return None # a string can be null
elif vtype == VariantType.DateTime:
return datetime.utcnow()
elif vtype == VariantType.Guid:
return uuid.uuid4()
elif vtype == VariantType.XmlElement:
return None #Not sure this is correct
elif vtype == VariantType.NodeId:
return NodeId()
elif vtype == VariantType.ExpandedNodeId:
return NodeId()
elif vtype == VariantType.StatusCode:
return StatusCode()
elif vtype == VariantType.QualifiedName:
return QualifiedName()
elif vtype == VariantType.LocalizedText:
return LocalizedText()
elif vtype == VariantType.ExtensionObject:
return ExtensionObject()
elif vtype == VariantType.DataValue:
return DataValue()
elif vtype == VariantType.Variant:
return Variant()
else:
raise RuntimeError("function take a uatype as argument, got:", vtype)
# These dictionnaries are used to register extensions classes for automatic
# decoding and encoding
extension_object_classes = {}
extension_object_ids = {}
[docs]def register_extension_object(name, nodeid, class_type):
"""
Register a new extension object for automatic decoding and make them available in ua module
"""
logger.info("registring new extension object: %s %s %s", name, nodeid, class_type)
extension_object_classes[nodeid] = class_type
extension_object_ids[name] = nodeid
# FIXME: Next line is not exactly a Python best practices, so feel free to propose something else
# add new extensions objects to ua modules to automate decoding
import opcua.ua
setattr(opcua.ua, name, class_type)
[docs]def get_extensionobject_class_type(typeid):
"""
Returns the registered class type for typid of an extension object
"""
if typeid in extension_object_classes:
return extension_object_classes[typeid]
else:
return None
[docs]class SecurityPolicyType(Enum):
"""
The supported types of SecurityPolicy.
"None"
"Basic128Rsa15_Sign"
"Basic128Rsa15_SignAndEncrypt"
"Basic256_Sign"
"Basic256_SignAndEncrypt"
"Basic256Sha256_Sign"
"Basic256Sha256_SignAndEncrypt"
"""
NoSecurity = 0
Basic128Rsa15_Sign = 1
Basic128Rsa15_SignAndEncrypt = 2
Basic256_Sign = 3
Basic256_SignAndEncrypt = 4
Basic256Sha256_Sign = 5
Basic256Sha256_SignAndEncrypt = 6