opcua.common.node.Node Class Reference

List of all members.

Public Member Functions
def	__eq__
def	__hash__
def	__init__
def	__ne__
def	__str__
def	add_data_type
def	add_folder
def	add_method
def	add_object
def	add_object_type
def	add_property
def	add_reference_type
def	add_variable
def	add_variable_type
def	call_method
def	delete
def	get_access_level
def	get_array_dimensions
def	get_attribute
def	get_attributes
def	get_browse_name
def	get_child
def	get_children
def	get_children_descriptions
def	get_data_type
def	get_data_type_as_variant_type
def	get_data_value
def	get_description
def	get_display_name
def	get_event_notifier
def	get_methods
def	get_node_class
def	get_parent
def	get_path
def	get_path_as_string
def	get_properties
def	get_referenced_nodes
def	get_references
def	get_type_definition
def	get_user_access_level
def	get_value
def	get_value_rank
def	get_variables
def	history_read
def	history_read_events
def	read_event_history
def	read_raw_history
def	set_array_dimensions
def	set_attr_bit
def	set_attribute
def	set_event_notifier
def	set_read_only
def	set_value
def	set_value_rank
def	set_writable
def	unset_attr_bit
Public Attributes
	nodeid
	server
Static Public Attributes
	set_data_value = set_value
Private Member Functions
def	_get_path
def	_make_relative_path
Static Private Attributes
	__repr__ = __str__

---

Detailed Description

High level node object, to access node attribute,
browse and populate address space.
Node objects are usefull as-is but they do not expose the entire
OPC-UA protocol. Feel free to look at the code of this class and call
directly UA services methods to optimize your code

Definition at line 10 of file node.py.

---

Constructor & Destructor Documentation

def opcua.common.node.Node.__init__	(		self,
			server,
			nodeid
	)

Definition at line 20 of file node.py.

---

Member Function Documentation

def opcua.common.node.Node.__eq__	(		self,
			other
	)

Definition at line 34 of file node.py.

def opcua.common.node.Node.__hash__

(

self

)

Definition at line 46 of file node.py.

def opcua.common.node.Node.__ne__	(		self,
			other
	)

Definition at line 39 of file node.py.

def opcua.common.node.Node.__str__

(

self

)

Definition at line 42 of file node.py.

def opcua.common.node.Node._get_path	(		self,
			max_length = 20
	)		[private]

Attempt to find path of node from root node and return it as a list of Nodes.
There might several possible paths to a node, this function will return one
Some nodes may be missing references, so this method may
return an empty list
Since address space may have circular references, a max length is specified

Definition at line 384 of file node.py.

def opcua.common.node.Node._make_relative_path	(		self,
			path
	)		[private]

Definition at line 439 of file node.py.

def opcua.common.node.Node.add_data_type	(		self,
			nodeid,
			bname,
			description = None
	)

Definition at line 569 of file node.py.

def opcua.common.node.Node.add_folder	(		self,
			nodeid,
			bname
	)

Definition at line 554 of file node.py.

def opcua.common.node.Node.add_method	(		self,
			args
	)

Definition at line 575 of file node.py.

def opcua.common.node.Node.add_object	(		self,
			nodeid,
			bname,
			objecttype = None
	)

Definition at line 557 of file node.py.

def opcua.common.node.Node.add_object_type	(		self,
			nodeid,
			bname
	)

Definition at line 563 of file node.py.

def opcua.common.node.Node.add_property	(		self,
			nodeid,
			bname,
			val,
			varianttype = None,
			datatype = None
	)

Definition at line 572 of file node.py.

def opcua.common.node.Node.add_reference_type	(		self,
			parent,
			nodeid,
			bname
	)

Definition at line 578 of file node.py.

def opcua.common.node.Node.add_variable	(		self,
			nodeid,
			bname,
			val,
			varianttype = None,
			datatype = None
	)

Definition at line 560 of file node.py.

def opcua.common.node.Node.add_variable_type	(		self,
			nodeid,
			bname,
			datatype
	)

Definition at line 566 of file node.py.

def opcua.common.node.Node.call_method	(		self,
			methodid,
			args
	)

Definition at line 581 of file node.py.

def opcua.common.node.Node.delete	(		self,
			delete_references = True
	)

Delete node from address space

Definition at line 542 of file node.py.

def opcua.common.node.Node.get_access_level

(

self

)

Get the access level attribute of the node as a set of AccessLevel enum values.

Definition at line 80 of file node.py.

def opcua.common.node.Node.get_array_dimensions

(

self

)

Read and return ArrayDimensions attribute of node

Definition at line 148 of file node.py.

def opcua.common.node.Node.get_attribute	(		self,
			attr
	)

Read one attribute of a node
result code from server is checked and an exception is raised in case of error

Definition at line 234 of file node.py.

def opcua.common.node.Node.get_attributes	(		self,
			attrs
	)

Read several attributes of a node
list of DataValue is returned

Definition at line 248 of file node.py.

def opcua.common.node.Node.get_browse_name

(

self

)

Get browse name of a node. A browse name is a QualifiedName object
composed of a string(name) and a namespace index.

Definition at line 49 of file node.py.

def opcua.common.node.Node.get_child	(		self,
			path
	)

get a child specified by its path from this node.
A path might be:
* a string representing a qualified name.
* a qualified name
* a list of string
* a list of qualified names

Definition at line 418 of file node.py.

def opcua.common.node.Node.get_children	(		self,
			refs = ua.ObjectIds.HierarchicalReferences,
			nodeclassmask = ua.NodeClass.Unspecified
	)

Get all children of a node. By default hierarchical references and all node classes are returned.
Other reference types may be given:
References = 31
NonHierarchicalReferences = 32
HierarchicalReferences = 33
HasChild = 34
Organizes = 35
HasEventSource = 36
HasModellingRule = 37
HasEncoding = 38
HasDescription = 39
HasTypeDefinition = 40
GeneratesEvent = 41
Aggregates = 44
HasSubtype = 45
HasProperty = 46
HasComponent = 47
HasNotifier = 48
HasOrderedComponent = 49

Definition at line 263 of file node.py.

def opcua.common.node.Node.get_children_descriptions	(		self,
			refs = ua.ObjectIds.HierarchicalReferences,
			nodeclassmask = ua.NodeClass.Unspecified,
			includesubtypes = True
	)

Definition at line 308 of file node.py.

def opcua.common.node.Node.get_data_type

(

self

)

get data type of node as NodeId

Definition at line 64 of file node.py.

def opcua.common.node.Node.get_data_type_as_variant_type

(

self

)

get data type of node as VariantType
This only works if node is a variable, otherwise type
may not be convertible to VariantType

Definition at line 71 of file node.py.

def opcua.common.node.Node.get_data_value

(

self

)

Get value of a node as a DataValue object. Only variables (and properties) have values.
An exception will be generated for other node types.
DataValue contain a variable value as a variant as well as server and source timestamps

Definition at line 132 of file node.py.

def opcua.common.node.Node.get_description

(

self

)

get description attribute class of node

Definition at line 117 of file node.py.

def opcua.common.node.Node.get_display_name

(

self

)

get description attribute of node

Definition at line 57 of file node.py.

def opcua.common.node.Node.get_event_notifier

(

self

)

Get the event notifier attribute of the node as a set of EventNotifier enum values.

Definition at line 94 of file node.py.

def opcua.common.node.Node.get_methods

(

self

)

return methods of node.
properties are child nodes with a reference of type HasComponent and a NodeClass of Method

Definition at line 301 of file node.py.

def opcua.common.node.Node.get_node_class

(

self

)

get node class attribute of node

Definition at line 110 of file node.py.

def opcua.common.node.Node.get_parent

(

self

)

returns parent of the node.
A Node may have several parents, the first found is returned.
This method uses reverse references, a node might be missing such a link,
thus we will not find its parent.

Definition at line 405 of file node.py.

def opcua.common.node.Node.get_path	(		self,
			max_length = 20
	)

Attempt to find path of node from root node and return it as a list of Nodes.
There might several possible paths to a node, this function will return one
Some nodes may be missing references, so this method may
return an empty list
Since address space may have circular references, a max length is specified

Definition at line 370 of file node.py.

def opcua.common.node.Node.get_path_as_string	(		self,
			max_length = 20
	)

Attempt to find path of node from root node and return it as a list of strings.
There might several possible paths to a node, this function will return one
Some nodes may be missing references, so this method may
return an empty list
Since address space may have circular references, a max length is specified

Definition at line 356 of file node.py.

def opcua.common.node.Node.get_properties

(

self

)

return properties of node.
properties are child nodes with a reference of type HasProperty and a NodeClass of Variable

Definition at line 287 of file node.py.

def opcua.common.node.Node.get_referenced_nodes	(		self,
			refs = ua.ObjectIds.References,
			direction = ua.BrowseDirection.Both,
			nodeclassmask = ua.NodeClass.Unspecified,
			includesubtypes = True
	)

returns referenced nodes based on specific filter
Paramters are the same as for get_references

Definition at line 334 of file node.py.

def opcua.common.node.Node.get_references	(		self,
			refs = ua.ObjectIds.References,
			direction = ua.BrowseDirection.Both,
			nodeclassmask = ua.NodeClass.Unspecified,
			includesubtypes = True
	)

returns references of the node based on specific filter defined with:

refs = ObjectId of the Reference
direction = Browse direction for references
nodeclassmask = filter nodes based on specific class
includesubtypes = If true subtypes of the reference (ref) are also included

Definition at line 311 of file node.py.

def opcua.common.node.Node.get_type_definition

(

self

)

returns type definition of the node.

Definition at line 347 of file node.py.

def opcua.common.node.Node.get_user_access_level

(

self

)

Get the user access level attribute of the node as a set of AccessLevel enum values.

Definition at line 87 of file node.py.

def opcua.common.node.Node.get_value

(

self

)

Get value of a node as a python type. Only variables ( and properties) have values.
An exception will be generated for other node types.

Definition at line 124 of file node.py.

def opcua.common.node.Node.get_value_rank

(

self

)

Read and return ArrayDimensions attribute of node

Definition at line 162 of file node.py.

def opcua.common.node.Node.get_variables

(

self

)

return variables of node.
properties are child nodes with a reference of type HasComponent and a NodeClass of Variable

Definition at line 294 of file node.py.

def opcua.common.node.Node.history_read	(		self,
			details
	)

Read raw history of a node, low-level function
result code from server is checked and an exception is raised in case of error

Definition at line 475 of file node.py.

def opcua.common.node.Node.history_read_events	(		self,
			details
	)

Read event history of a node, low-level function
result code from server is checked and an exception is raised in case of error

Definition at line 525 of file node.py.

def opcua.common.node.Node.read_event_history	(		self,
			starttime = None,
			endtime = None,
			numvalues = 0,
			evtypes = ua.ObjectIds.BaseEventType
	)

Read event history of a source node
result code from server is checked and an exception is raised in case of error
If numvalues is > 0 and number of events in period is > numvalues
then result will be truncated

Definition at line 492 of file node.py.

def opcua.common.node.Node.read_raw_history	(		self,
			starttime = None,
			endtime = None,
			numvalues = 0
	)

Read raw history of a node
result code from server is checked and an exception is raised in case of error
If numvalues is > 0 and number of events in period is > numvalues
then result will be truncated

Definition at line 453 of file node.py.

def opcua.common.node.Node.set_array_dimensions	(		self,
			value
	)

Set attribute ArrayDimensions of node
make sure it has the correct data type

Definition at line 140 of file node.py.

def opcua.common.node.Node.set_attr_bit	(		self,
			attr,
			bit
	)

Definition at line 202 of file node.py.

def opcua.common.node.Node.set_attribute	(		self,
			attributeid,
			datavalue
	)

Set an attribute of a node
attributeid is a member of ua.AttributeIds
datavalue is a ua.DataValue object

Definition at line 219 of file node.py.

def opcua.common.node.Node.set_event_notifier	(		self,
			values
	)

Set the event notifier attribute.

:param values: an iterable of EventNotifier enum values.

Definition at line 101 of file node.py.

def opcua.common.node.Node.set_read_only

(

self

)

Set a node as read-only for clients.
A node is always writable on server side.

Definition at line 212 of file node.py.

def opcua.common.node.Node.set_value	(		self,
			value,
			varianttype = None
	)

Set value of a node. Only variables(properties) have values.
An exception will be generated for other node types.
value argument is either:
* a python built-in type, converted to opc-ua
optionnaly using the variantype argument.
* a ua.Variant, varianttype is then ignored
* a ua.DataValue, you then have full control over data send to server

Definition at line 169 of file node.py.

def opcua.common.node.Node.set_value_rank	(		self,
			value
	)

Set attribute ArrayDimensions of node

Definition at line 155 of file node.py.

def opcua.common.node.Node.set_writable	(		self,
			writable = True
	)

Set node as writable by clients.
A node is always writable on server side.

Definition at line 190 of file node.py.

def opcua.common.node.Node.unset_attr_bit	(		self,
			attr,
			bit
	)

Definition at line 207 of file node.py.

---

Member Data Documentation

opcua::common::node.Node::__repr__ = __str__ [static, private]

Definition at line 44 of file node.py.

opcua::common::node.Node::nodeid

Definition at line 20 of file node.py.

opcua::common::node.Node::server

Definition at line 20 of file node.py.

opcua::common::node.Node::set_data_value = set_value [static]

Definition at line 188 of file node.py.

---

The documentation for this class was generated from the following file:

• node.py