Struct Variable 

pub struct Variable { /* private fields */ }

A Variable is a type of node within the AddressSpace.

Implementations

impl Variable

pub fn new( node_id: &NodeId, browse_name: impl Into<QualifiedName>, display_name: impl Into<LocalizedText>, value: impl Into<Variant>, ) -> Variable

Creates a new variable. Note that data type, value rank and historizing are mandatory attributes of the Variable but not required by the constructor. The data type and value rank are inferred from the value. Historizing is not supported so is always false. If the inferred types for data type or value rank are wrong, they may be explicitly set, or call new_data_value() instead.

pub fn new_full( base: Base, data_type: NodeId, historizing: bool, value_rank: i32, value: DataValue, access_level: u8, user_access_level: u8, array_dimensions: Option<Vec<u32>>, minimum_sampling_interval: Option<f64>, ) -> Self

Create a new variable with all attributes, may change if new attributes are added to the OPC-UA standard.

Note: This uses the given value and data type directly, you must ensure that the type of the value matches the data type.

pub fn from_attributes( node_id: &NodeId, browse_name: impl Into<QualifiedName>, attributes: VariableAttributes, ) -> Result<Self, FromAttributesError>

Create a new variable from VariableAttributes.

pub fn new_data_value<S, R, N, V>( node_id: &NodeId, browse_name: R, display_name: S, data_type: N, value_rank: Option<i32>, array_dimensions: Option<u32>, value: V, ) -> Variable

where R: Into<QualifiedName>, S: Into<LocalizedText>, N: Into<NodeId>, V: Into<Variant>,

Constructs a new variable with the specified id, name, type and value

pub fn is_valid(&self) -> bool

Get whether this is a valid instance of a variable.

pub fn value( &self, timestamps_to_return: TimestampsToReturn, index_range: &NumericRange, _data_encoding: &DataEncoding, _max_age: f64, ) -> DataValue

Read the value of the variable.

pub fn set_value<V>( &mut self, index_range: &NumericRange, value: V, ) -> Result<(), StatusCode>

where V: Into<Variant>,

Sets the variable’s Variant value. The timestamps for the change are updated to now.

pub fn set_value_range( &mut self, value: Variant, index_range: &NumericRange, status_code: StatusCode, server_timestamp: &DateTime, source_timestamp: &DateTime, ) -> Result<(), StatusCode>

Set a part of the current value given by index_range.

pub fn set_value_direct<V>( &mut self, value: V, status_code: StatusCode, server_timestamp: &DateTime, source_timestamp: &DateTime, ) -> Result<(), StatusCode>

where V: Into<Variant>,

Sets the variable’s DataValue

pub fn set_data_value(&mut self, value: DataValue)

Sets the variable type’s DataValue

pub fn minimum_sampling_interval(&self) -> Option<f64>

Gets the minimum sampling interval, if the attribute was set

pub fn set_minimum_sampling_interval(&mut self, minimum_sampling_interval: f64)

Sets the minimum sampling interval

Specifies in milliseconds how fast the server can reasonably sample the value for changes

The value 0 means server is to monitor the value continuously. The value -1 means indeterminate.

pub fn is_readable(&self) -> bool

Test if the variable is readable. This will be called by services before getting the value of the node.

pub fn is_writable(&self) -> bool

Test if the variable is writable. This will be called by services before setting the value on the node.

pub fn set_writable(&mut self, writable: bool)

Sets the variable writable state.

pub fn access_level(&self) -> AccessLevel

Returns the access level of the variable.

pub fn set_access_level(&mut self, access_level: AccessLevel)

Sets the access level of the variable.

pub fn is_user_readable(&self) -> bool

Test if the variable is user readable.

pub fn is_user_writable(&self) -> bool

Test if the variable is user writable.

pub fn user_access_level(&self) -> AccessLevel

Returns the user access level of the variable.

pub fn set_user_access_level(&mut self, user_access_level: AccessLevel)

Set the user access level of the variable.

pub fn value_rank(&self) -> i32

Get the variable value rank.

pub fn set_value_rank(&mut self, value_rank: i32)

Set the variable value rank.

pub fn historizing(&self) -> bool

Get the Historizing attribute of the variable, whether it stores new values in a historical store.

pub fn set_historizing(&mut self, historizing: bool)

Set the Historizing attribute of the variable, whether it stores new values in a historical store.

pub fn array_dimensions(&self) -> Option<Vec<u32>>

Get the array dimensions of this variable.

pub fn set_array_dimensions(&mut self, array_dimensions: &[u32])

Set the array dimensions of this variable.

pub fn data_type(&self) -> NodeId

Get the data type of this variable.

pub fn set_data_type(&mut self, data_type: impl Into<NodeId>)

Set the data type of this variable.

Trait Implementations

impl Debug for Variable

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Variable

fn default() -> Self

Returns the “default value” for a type.

impl From<Variable> for NodeType

fn from(value: Variable) -> Self

Converts to this type from the input type.

impl Node for Variable

fn get_attribute_max_age( &self, timestamps_to_return: TimestampsToReturn, attribute_id: AttributeId, index_range: &NumericRange, data_encoding: &DataEncoding, max_age: f64, ) -> Option<DataValue>

Finds the attribute and value. The param max_age is a hint in milliseconds:

fn set_attribute( &mut self, attribute_id: AttributeId, value: Variant, ) -> Result<(), StatusCode>

Sets the attribute with the new value

fn get_attribute( &self, timestamps_to_return: TimestampsToReturn, attribute_id: AttributeId, index_range: &NumericRange, data_encoding: &DataEncoding, ) -> Option<DataValue>

Finds the attribute and value.

impl NodeBase for Variable

fn node_class(&self) -> NodeClass

Returns the node class - Object, ObjectType, Method, DataType, ReferenceType, Variable, VariableType or View

fn node_id(&self) -> &NodeId

Returns the node’s NodeId

fn browse_name(&self) -> &QualifiedName

Returns the node’s browse name

fn display_name(&self) -> &LocalizedText

Returns the node’s display name

fn set_display_name(&mut self, display_name: LocalizedText)

Sets the node’s display name

fn description(&self) -> Option<&LocalizedText>

Get the description of this node.

fn set_description(&mut self, description: LocalizedText)

Set the description of this node.

fn write_mask(&self) -> Option<WriteMask>

Get the write mask of this node.

fn set_write_mask(&mut self, write_mask: WriteMask)

Set the write mask of this node.

fn user_write_mask(&self) -> Option<WriteMask>

Get the user write mask for this node.

fn set_user_write_mask(&mut self, user_write_mask: WriteMask)

Set the user write mask for this node.