A Xentara attribute. More...

#include <xentara/model/Attribute.hpp>

Classes
class	Role
	A built-in attribute role. More...

Public Types
enum class	Access { ReadOnly , WriteOnly , ReadWrite }
	An Access type for an attribute. More...

Public Member Functions
constexpr	Attribute (const Role &role, Access access, std::reference_wrapper< const data::DataType > dataType)
	Constructor for attributes with built-in roles.

constexpr	Attribute (const utils::core::Uuid &uuid, std::string_view name, Access access, std::reference_wrapper< const data::DataType > dataType, io::Directions ioDirections={})
	Constructor for custom attributes.

auto	name () const -> const std::string_view &
	Gets the name.

auto	uuid () const -> const utils::core::Uuid &
	Gets the UUID.

auto	access () const -> Access
	Gets the access modes.

auto	dataType () const -> const data::DataType &
	Gets the data type.

auto	ioDirections () const -> io::Directions
	Gets the relevant I/O directions.

auto	setAccess (Access access) -> void
	Sets the access modes.

auto	setDataType (std::reference_wrapper< const data::DataType > dataType) -> void
	Sets the data type.

auto	setIoDirections (io::Directions ioDirections) -> void
	Sets the relevant I/O directions.

auto	operator== (const Attribute &rhs) const -> bool
	Checks whether a reference refers to this attribute.

template<utils::tools::EqualityComparableWithExcept< std::string_view, Attribute > String>
auto	operator== (const String &rhs) const -> bool
	Checks the name of the attribute.

template<utils::tools::EqualityComparableWithExcept< utils::core::Uuid, Attribute > UUID>
auto	operator== (const UUID &rhs) const -> bool
	Checks the UUID of the attribute.

auto	operator== (const Role &rhs) const -> bool
	Checks the role of the attribute.

Static Public Member Functions
Deprecated Functions
template<std::equality_comparable_with< std::string_view > String, typename... Attributes>
static auto	resolve (const String &name, const Attribute &firstAttribute, const Attributes &... moreAttributes) -> const Attribute *
	deprecated Checks the name of a list of attributes and returns the first one that matches

Static Public Attributes
Standard Attributes
static const Attribute	kPrimaryKey
	The attribute for the primary key of an element.

static const Attribute	kName
	The attribute for the name of an element.

static const Attribute	kUuid
	The attribute for the UUID of an element.

static const Attribute	kType
	The attribute for the type (class) of an element.

static const Attribute	kCategory
	The attribute for the element category of an element.

static const Attribute	kSourceTime
	The attribute for the time stamp of a value provided by the data source, like the device.

static const Attribute	kUpdateTime
	The attribute for the update time stamp of a value.

static const Attribute	kChangeTime
	The attribute for the change time stamp of a value.

static const Attribute	kWriteTime
	The attribute for the time stamp of the last attempted write operation of an output.

static const Attribute	kQuality
	The attribute for the quality of a value.

static const Attribute	kDeviceState
	The attribute for the state of a device.

Standard Roles
static const Role	kValue
	The role for a value.

static const Role	kError
	The standard name for an error.

static const Role	kWriteError
	The standard name for a write error.

Standard Names
static const std::string_view	kAddress
	The standard name for an address.

static const std::string_view	kOffset
	The standard name for an offset.

static const std::string_view	kLength
	The standard name for a length.

static const std::string_view	kChannel
	The standard name for a channel.

static const std::string_view	kDataType
	The role for a data type.

Deprecated Constants
static constexpr Access	ReadOnly
	deprecated Unscoped access to Access::ReadOnly

static constexpr Access	WriteOnly
	deprecated Unscoped access to Access::WriteOnly

static constexpr Access	ReadWrite
	deprecated Unscoped access to Access::ReadWrite

Detailed Description

A Xentara attribute.

Note: This class merely identifies the attribute, it does not represent the attribute of an individual element. To access the attribute of a specific Xentara element, use the the class ElementAttribute.

See also: ElementAttribute; Attributes in the Xentara user manual

Examples: PublishingConfigAttributes.cpp.

Member Enumeration Documentation

◆ Access

enum class xentara::model::Attribute::Access

strong

An Access type for an attribute.

Enumerator
ReadOnly	The attribute supports reading only.
WriteOnly	The attribute supports writing only.
ReadWrite	The attribute supports reading and writing.

Constructor & Destructor Documentation

◆ Attribute() [1/2]

constexpr xentara::model::Attribute::Attribute	(	const Role &	role,
		Access	access,
		std::reference_wrapper< const data::DataType >	dataType
	)

constexpr

Constructor for attributes with built-in roles.

Parameters

role	The role of the attribute.
access	The possible access modes for the attribute
dataType	The data type of the attribute

◆ Attribute() [2/2]

constexpr xentara::model::Attribute::Attribute	(	const utils::core::Uuid &	uuid,
		std::string_view	name,
		Access	access,
		std::reference_wrapper< const data::DataType >	dataType,
		io::Directions	ioDirections = `{}`
	)

constexpr

Constructor for custom attributes.

Parameters

uuid	The UUID of the attribute
name	The name of the attribute, in UTF-8 encoding. The string data the view references to is not copied. It must remain valid for the lifetime of the plugin.

To keep naming conventions as consistent as possible between plugins, Xentara provides a set of predefined attribute names. All things being equal, you should prefer using one of the predefines names. If the documentation, the specification, or common usage for your plugin use different nomenclature, however, you should prefer that over the standard names.

If your attribute references another element, you sould use the name of the element. If your attribute references an I/O device, for example, you should use xentara::io::ComponentClass::kDevice as the name.

Parameters

access The possible access modes for the attribute

dataType The data type of the attribute

ioDirections

The relevant I/O directions.

The I/O directions are used for I/O attributes to specify whether a data point should inherit this attribute from its attached input and/or output. If the directions contain the flag io::Direction::Input, then the data point will inherit this attribute from its input. If the directions contain the flag io::Direction::Output, then the data point will inherit this attribute from its output. If you do not set either flag (the default), then the attribute will not be considered an I/O attribute and will not be inherited by any data points.

Member Function Documentation

◆ access()

auto xentara::model::Attribute::access ( ) const -> Access

Gets the access modes.

◆ dataType()

auto xentara::model::Attribute::dataType ( ) const -> const data::DataType &

Gets the data type.

◆ ioDirections()

auto xentara::model::Attribute::ioDirections ( ) const -> io::Directions

Gets the relevant I/O directions.

Returns: The I/O directions. The I/O directions are used for I/O attributes to specify whether a data point should inherit this attribute from its attached input and/or output.

◆ name()

auto xentara::model::Attribute::name ( ) const -> const std::string_view &

Gets the name.

Returns: The name, in UTF-8 encoding

◆ operator==() [1/4]

auto xentara::model::Attribute::operator== ( const Attribute & rhs ) const -> bool

Checks whether a reference refers to this attribute.

This operator checks the identity of the objects, not the properties. The operator returns true only if the rhs refers to the same object as this. It is equivalent to this == std::addressof(rhs).

Returns: Returns true if the attribute has the given name.

◆ operator==() [2/4]

auto xentara::model::Attribute::operator== ( const Role & rhs ) const -> bool

Checks the role of the attribute.

This is a convenience operator you can use to check the UUID of an attribute. It is equivalent to uuid() == rhs.uuid().

Returns: Returns true if the attribute has the same UUID as the role.

◆ operator==() [3/4]

template<utils::tools::EqualityComparableWithExcept< std::string_view, Attribute > String>

auto xentara::model::Attribute::operator== ( const String & rhs ) const -> bool

Checks the name of the attribute.

This is a convenience operator you can use to check the name of an attribute. It is equivalent to name() == rhs.

Returns: Returns true if the attribute has the given name.

◆ operator==() [4/4]

template<utils::tools::EqualityComparableWithExcept< utils::core::Uuid, Attribute > UUID>

auto xentara::model::Attribute::operator== ( const UUID & rhs ) const -> bool

Checks the UUID of the attribute.

This is a convenience operator you can use to check the UUID of an attribute. It is equivalent to uuid() == rhs.

Returns: Returns true if the attribute has the given UUID.

◆ resolve()

template<std::equality_comparable_with< std::string_view > String, typename... Attributes>

static auto xentara::model::Attribute::resolve	(	const String &	name,
		const Attribute &	firstAttribute,
		const Attributes &...	moreAttributes
	)		-> const Attribute *

static

deprecated Checks the name of a list of attributes and returns the first one that matches

Deprecated:: This function is no longer used

◆ setAccess()

auto xentara::model::Attribute::setAccess ( Access access ) -> void

Sets the access modes.

◆ setDataType()

auto xentara::model::Attribute::setDataType ( std::reference_wrapper< const data::DataType > dataType ) -> void

Sets the data type.

◆ setIoDirections()

auto xentara::model::Attribute::setIoDirections ( io::Directions ioDirections ) -> void

Sets the relevant I/O directions.

Parameters

ioDirections The desired I/O directions. The I/O directions are used for I/O attributes to specify whether a data point should inherit this attribute from its attached input and/or output.

◆ uuid()

auto xentara::model::Attribute::uuid ( ) const -> const utils::core::Uuid &

Gets the UUID.

Member Data Documentation

◆ kAddress

const std::string_view xentara::model::Attribute::kAddress

static

The standard name for an address.

◆ kCategory

const Attribute xentara::model::Attribute::kCategory

static

The attribute for the element category of an element.

◆ kChangeTime

const Attribute xentara::model::Attribute::kChangeTime

static

The attribute for the change time stamp of a value.

◆ kChannel

const std::string_view xentara::model::Attribute::kChannel

static

The standard name for a channel.

◆ kDataType

const std::string_view xentara::model::Attribute::kDataType

static

The role for a data type.

◆ kDeviceState

const Attribute xentara::model::Attribute::kDeviceState

static

The attribute for the state of a device.

◆ kError

const Role xentara::model::Attribute::kError

static

The standard name for an error.

◆ kLength

const std::string_view xentara::model::Attribute::kLength

static

The standard name for a length.

◆ kName

const Attribute xentara::model::Attribute::kName

static

The attribute for the name of an element.

◆ kOffset

const std::string_view xentara::model::Attribute::kOffset

static

The standard name for an offset.

◆ kPrimaryKey

const Attribute xentara::model::Attribute::kPrimaryKey

static

The attribute for the primary key of an element.

◆ kQuality

const Attribute xentara::model::Attribute::kQuality

static

The attribute for the quality of a value.

◆ kSourceTime

const Attribute xentara::model::Attribute::kSourceTime

static

The attribute for the time stamp of a value provided by the data source, like the device.

◆ kType

const Attribute xentara::model::Attribute::kType

static

The attribute for the type (class) of an element.

◆ kUpdateTime

const Attribute xentara::model::Attribute::kUpdateTime

static

The attribute for the update time stamp of a value.

◆ kUuid

const Attribute xentara::model::Attribute::kUuid

static

The attribute for the UUID of an element.

◆ kValue

const Role xentara::model::Attribute::kValue

static

The role for a value.

◆ kWriteError

const Role xentara::model::Attribute::kWriteError

static

The standard name for a write error.

◆ kWriteTime

const Attribute xentara::model::Attribute::kWriteTime

static

The attribute for the time stamp of the last attempted write operation of an output.

◆ ReadOnly

constexpr Access xentara::model::Attribute::ReadOnly

staticconstexpr

deprecated Unscoped access to Access::ReadOnly

Deprecated:: This is a backwards compatibility constant to account for the formerly unscoped enum Attribute::Access

◆ ReadWrite

constexpr Access xentara::model::Attribute::ReadWrite

staticconstexpr

deprecated Unscoped access to Access::ReadWrite

Deprecated:: This is a backwards compatibility constant to account for the formerly unscoped enum Attribute::Access

◆ WriteOnly

constexpr Access xentara::model::Attribute::WriteOnly

staticconstexpr

deprecated Unscoped access to Access::WriteOnly

Deprecated:: This is a backwards compatibility constant to account for the formerly unscoped enum Attribute::Access

Classes

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Detailed Description

Member Enumeration Documentation

◆ Access

Constructor & Destructor Documentation

◆ Attribute() [1/2]

◆ Attribute() [2/2]

Member Function Documentation

◆ access()

◆ dataType()

◆ ioDirections()

◆ name()

◆ operator==() [1/4]

◆ operator==() [2/4]

◆ operator==() [3/4]

◆ operator==() [4/4]

◆ resolve()

◆ setAccess()

◆ setDataType()

◆ setIoDirections()

◆ uuid()

Member Data Documentation

◆ kAddress

◆ kCategory

◆ kChangeTime

◆ kChannel

◆ kDataType

◆ kDeviceState

◆ kError

◆ kLength

◆ kName

◆ kOffset

◆ kPrimaryKey

◆ kQuality

◆ kSourceTime

◆ kType

◆ kUpdateTime

◆ kUuid

◆ kValue

◆ kWriteError

◆ kWriteTime

◆ ReadOnly

◆ ReadWrite

◆ WriteOnly