miden_protocol/note/
header.rs

1use super::{
2    ByteReader,
3    ByteWriter,
4    Deserializable,
5    DeserializationError,
6    NoteId,
7    NoteMetadata,
8    Serializable,
9    Word,
10};
11use crate::Hasher;
12
13// NOTE HEADER
14// ================================================================================================
15
16/// Holds the strictly required, public information of a note.
17///
18/// See [NoteId] and [NoteMetadata] for additional details.
19#[derive(Debug, Clone, PartialEq, Eq)]
20pub struct NoteHeader {
21    note_id: NoteId,
22    note_metadata: NoteMetadata,
23}
24
25impl NoteHeader {
26    /// Returns a new [NoteHeader] instantiated from the specified note ID and metadata.
27    pub fn new(note_id: NoteId, note_metadata: NoteMetadata) -> Self {
28        Self { note_id, note_metadata }
29    }
30
31    /// Returns the note's identifier.
32    ///
33    /// The [NoteId] value is both an unique identifier and a commitment to the note.
34    pub fn id(&self) -> NoteId {
35        self.note_id
36    }
37
38    /// Returns the note's metadata.
39    pub fn metadata(&self) -> &NoteMetadata {
40        &self.note_metadata
41    }
42
43    /// Consumes self and returns the note header's metadata.
44    pub fn into_metadata(self) -> NoteMetadata {
45        self.note_metadata
46    }
47
48    /// Returns a commitment to the note and its metadata.
49    ///
50    /// > hash(NOTE_ID || NOTE_METADATA_COMMITMENT)
51    ///
52    /// This value is used primarily for authenticating notes consumed when they are consumed
53    /// in a transaction.
54    pub fn commitment(&self) -> Word {
55        compute_note_commitment(self.id(), self.metadata())
56    }
57}
58
59// UTILITIES
60// ================================================================================================
61
62/// Returns a commitment to the note and its metadata.
63///
64/// > hash(NOTE_ID || NOTE_METADATA_COMMITMENT)
65///
66/// This value is used primarily for authenticating notes consumed when they are consumed
67/// in a transaction.
68pub fn compute_note_commitment(id: NoteId, metadata: &NoteMetadata) -> Word {
69    Hasher::merge(&[id.as_word(), metadata.to_commitment()])
70}
71
72// SERIALIZATION
73// ================================================================================================
74
75impl Serializable for NoteHeader {
76    fn write_into<W: ByteWriter>(&self, target: &mut W) {
77        self.note_id.write_into(target);
78        self.note_metadata.write_into(target);
79    }
80}
81
82impl Deserializable for NoteHeader {
83    fn read_from<R: ByteReader>(source: &mut R) -> Result<Self, DeserializationError> {
84        let note_id = NoteId::read_from(source)?;
85        let note_metadata = NoteMetadata::read_from(source)?;
86
87        Ok(Self { note_id, note_metadata })
88    }
89}
miden_protocol/note/header.rs

miden_protocol/note/
header.rs
