Struct NoteAttachment 

pub struct NoteAttachment { /* private fields */ }

The optional attachment for a Note.

An attachment is a public extension to a note.

Example use cases:

• Communicate the NoteDetails of a private note in encrypted form.
• In the context of network transactions, encode the ID of the network account that should consume the note.
• Communicate details to the receiver of a private note to allow deriving the NoteDetails of that note. For instance, the payback note of a partial swap note can be private, but the receiver needs to know additional details to fully derive the content of the payback note. They can neither fetch those details from the network, since the note is private, nor is a side-channel available. The note attachment can encode those details.

Next to the content, a note attachment can optionally specify a NoteAttachmentScheme. This allows a note attachment to describe itself. For example, a network account target attachment can be identified by a standardized type. For cases when the attachment scheme is known from content or typing is otherwise undesirable, NoteAttachmentScheme::none can be used.

Implementations

impl NoteAttachment

pub const MAX_NUM_WORDS: u16 = 256

The maximum number of words in an attachment.

Each element holds roughly 8 bytes of data and so this allows for a maximum of 256 * 32 = 2^13 = 8192 bytes.

pub fn new( attachment_scheme: NoteAttachmentScheme, content: NoteAttachmentContent, ) -> Self

Creates a new NoteAttachment from a user-defined scheme and the provided content.

pub fn with_word(attachment_scheme: NoteAttachmentScheme, word: Word) -> Self

Creates a new note attachment from a single word.

pub fn with_words( attachment_scheme: NoteAttachmentScheme, words: Vec<Word>, ) -> Result<Self, NoteError>

Creates a new note attachment from the provided words.

Errors

Returns an error if:

• words is empty.
• The number of words exceeds NoteAttachment::MAX_NUM_WORDS.

pub fn attachment_scheme(&self) -> NoteAttachmentScheme

Returns the attachment scheme.

pub fn content(&self) -> &NoteAttachmentContent

Returns a reference to the attachment content.

pub fn to_commitment(&self) -> Word

Computes the commitment of the attachment.

pub fn as_elements(&self) -> &[Felt]

Returns the raw elements of this attachment content.

pub fn to_elements(&self) -> Vec<Felt>

Returns the raw elements of this attachment content.

pub fn num_words(&self) -> u16

Returns the size of this attachment in words (1 to Self::MAX_NUM_WORDS).

Trait Implementations

impl Clone for NoteAttachment

fn clone(&self) -> NoteAttachment

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for NoteAttachment

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

Formats the value using the given formatter.

impl Deserializable for NoteAttachment

fn read_from<R: ByteReader>( source: &mut R, ) -> Result<Self, DeserializationError>

Reads a sequence of bytes from the provided source, attempts to deserialize these bytes into Self, and returns the result.

fn min_serialized_size() -> usize

Returns the minimum serialized size for one instance of this type.

fn read_from_bytes(bytes: &[u8]) -> Result<Self, DeserializationError>

Attempts to deserialize the provided bytes into Self and returns the result.

fn read_from_bytes_with_budget( bytes: &[u8], budget: usize, ) -> Result<Self, DeserializationError>

Deserializes Self from bytes with a byte budget limit.

impl From<NoteAttachment> for NoteAttachments

fn from(attachment: NoteAttachment) -> Self

Converts to this type from the input type.

impl PartialEq for NoteAttachment

fn eq(&self, other: &NoteAttachment) -> 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 Serializable for NoteAttachment

fn write_into<W: ByteWriter>(&self, target: &mut W)

Serializes self into bytes and writes these bytes into the target.

fn get_size_hint(&self) -> usize

Returns an estimate of how many bytes are needed to represent self.

fn to_bytes(&self) -> Vec<u8>

Serializes self into a vector of bytes.

impl Eq for NoteAttachment

impl StructuralPartialEq for NoteAttachment