Struct opcua_core::prelude::DataValue

pub struct DataValue {
    pub value: Option<Variant>,
    pub status: Option<StatusCode>,
    pub source_timestamp: Option<DateTime>,
    pub source_picoseconds: Option<i16>,
    pub server_timestamp: Option<DateTime>,
    pub server_picoseconds: Option<i16>,
}

A data value is a value of a variable in the OPC UA server and contains information about its value, status and change timestamps.

Fields

value: Option<Variant>

The value. BaseDataType Not present if the Value bit in the EncodingMask is False.

status: Option<StatusCode>

The status associated with the value. Not present if the StatusCode bit in the EncodingMask is False

source_timestamp: Option<DateTime>

The source timestamp associated with the value. Not present if the SourceTimestamp bit in the EncodingMask is False.

source_picoseconds: Option<i16>

The number of 10 picosecond intervals for the SourceTimestamp. Not present if the SourcePicoSeconds bit in the EncodingMask is False. If the source timestamp is missing the picoseconds are ignored.

server_timestamp: Option<DateTime>

The Server timestamp associated with the value. Not present if the ServerTimestamp bit in the EncodingMask is False.

server_picoseconds: Option<i16>

The number of 10 picosecond intervals for the ServerTimestamp. Not present if the ServerPicoSeconds bit in the EncodingMask is False. If the Server timestamp is missing the picoseconds are ignored.

Implementations

impl DataValue

pub fn value_only<V>(value: V) -> DataValue where
    V: Into<Variant>, 

Creates a DataValue from the supplied value with nothing else.

pub fn new_now<V>(value: V) -> DataValue where
    V: Into<Variant>, 

Creates a DataValue from the supplied value AND a timestamp for now. If you are passing a value to the Attribute::Write service on a server from a server, you may consider this from the specification:

If the SourceTimestamp or the ServerTimestamp is specified, the Server shall use these values. The Server returns a Bad_WriteNotSupported error if it does not support writing of timestamps

In which case, use the value_only() constructor, or make explicit which fields you pass.

pub fn null() -> DataValue

Creates an empty DataValue

pub fn set_value<V>(
    &mut self,
    value: V,
    source_timestamp: &DateTime,
    server_timestamp: &DateTime
) where
    V: Into<Variant>, 

Sets the value of the data value, updating the timestamps at the same point

pub fn set_timestamps(
    &mut self,
    timestamps_to_return: TimestampsToReturn,
    source_timestamp: DateTime,
    server_timestamp: DateTime
)

Sets the timestamps of the data value based on supplied timestamps to return

pub fn status(&self) -> StatusCode

Returns the status code or Good if there is no code on the value

pub fn is_valid(&self) -> bool

Test if the value held by this data value is known to be good Anything other than Good is assumed to be invalid.

Trait Implementations

impl BinaryEncoder<DataValue> for DataValue

fn byte_len(&self) -> usize

Returns the exact byte length of the structure as it would be if encode were called. This may be called prior to writing to ensure the correct amount of space is available.

fn encode<S>(&self, stream: &mut S) -> Result<usize, StatusCode> where
    S: Write, 

Encodes the instance to the write stream.

fn decode<S>(
    stream: &mut S,
    decoding_options: &DecodingOptions
) -> Result<DataValue, StatusCode> where
    S: Read, 

Decodes an instance from the read stream. The decoding options contains restrictions set by the server / client on the length of strings, arrays etc. If these limits are exceeded the implementation should return with a BadDecodingError as soon as possible.

fn encode_to_vec(&self) -> Vec<u8, Global>

impl Clone for DataValue

fn clone(&self) -> DataValue

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DataValue

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

Formats the value using the given formatter.

impl Default for DataValue

fn default() -> DataValue

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for DataValue

fn deserialize<__D>(
    __deserializer: __D
) -> Result<DataValue, <__D as Deserializer<'de>>::Error> where
    __D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.

impl<'a> From<&'a str> for DataValue

fn from(v: &'a str) -> DataValue

Converts to this type from the input type.

impl From<(Variant, StatusCode)> for DataValue

fn from(v: (Variant, StatusCode)) -> DataValue

Converts to this type from the input type.

impl From<ByteString> for DataValue

fn from(v: ByteString) -> DataValue

Converts to this type from the input type.

impl From<DataValue> for Variant

fn from(v: DataValue) -> Variant

Converts to this type from the input type.

impl From<DateTime> for DataValue

fn from(v: DateTime) -> DataValue

Converts to this type from the input type.

impl From<Guid> for DataValue

fn from(v: Guid) -> DataValue

Converts to this type from the input type.

impl From<LocalizedText> for DataValue

fn from(v: LocalizedText) -> DataValue

Converts to this type from the input type.

impl From<NodeId> for DataValue

fn from(v: NodeId) -> DataValue

Converts to this type from the input type.

impl From<QualifiedName> for DataValue

fn from(v: QualifiedName) -> DataValue

Converts to this type from the input type.

impl From<StatusCode> for DataValue

fn from(v: StatusCode) -> DataValue

Converts to this type from the input type.

impl From<String> for DataValue

fn from(v: String) -> DataValue

Converts to this type from the input type.

impl From<UAString> for DataValue

fn from(v: UAString) -> DataValue

Converts to this type from the input type.

impl From<Variant> for DataValue

fn from(v: Variant) -> DataValue

Converts to this type from the input type.

impl From<bool> for DataValue

fn from(v: bool) -> DataValue

Converts to this type from the input type.

impl From<f32> for DataValue

fn from(v: f32) -> DataValue

Converts to this type from the input type.

impl From<f64> for DataValue

fn from(v: f64) -> DataValue

Converts to this type from the input type.

impl From<i16> for DataValue

fn from(v: i16) -> DataValue

Converts to this type from the input type.

impl From<i32> for DataValue

fn from(v: i32) -> DataValue

Converts to this type from the input type.

impl From<i64> for DataValue

fn from(v: i64) -> DataValue

Converts to this type from the input type.

impl From<i8> for DataValue

fn from(v: i8) -> DataValue

Converts to this type from the input type.

impl From<u16> for DataValue

fn from(v: u16) -> DataValue

Converts to this type from the input type.

impl From<u32> for DataValue

fn from(v: u32) -> DataValue

Converts to this type from the input type.

impl From<u64> for DataValue

fn from(v: u64) -> DataValue

Converts to this type from the input type.

impl From<u8> for DataValue

fn from(v: u8) -> DataValue

Converts to this type from the input type.

impl PartialEq<DataValue> for DataValue

fn eq(&self, other: &DataValue) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &DataValue) -> bool

This method tests for !=.

impl Serialize for DataValue

fn serialize<__S>(
    &self,
    __serializer: __S
) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error> where
    __S: Serializer, 

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for DataValue