Struct Metadata 

pub struct Metadata {
    pub key: String,
    pub value: Vec<u8>,
}

Metadata: auxiliary data attached to state transitions

Examples: timestamps, annotations, oracle feeds. Metadata is not validated by the VM and is opaque to consensus.

Fields

key: String

Metadata key (human-readable identifier)

value: Vec<u8>

Serialized metadata value

Implementations

impl Metadata

pub fn new(key: impl Into<String>, value: Vec<u8>) -> Self

Create new metadata

pub fn from_string(key: impl Into<String>, value: impl Into<String>) -> Self

Create metadata from a string value

pub fn as_string(&self) -> Option<String>

Try to decode value as UTF-8 string

Trait Implementations

impl Clone for Metadata

fn clone(&self) -> Metadata

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Metadata

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Metadata

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Hash for Metadata

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Metadata

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for Metadata

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for Metadata

impl StructuralPartialEq for Metadata