Struct ChainAnchor 

pub struct ChainAnchor { /* private fields */ }

A self-contained, verifiable anchor for executing a transaction against a specific reference block instead of the client’s current sync height.

The anchor bundles the reference BlockHeader with a PartialBlockchain consistent with it — exactly the chain data TransactionInputs requires: chain_length() equals the header’s block number and the peaks hash to the header’s chain commitment. Both invariants are enforced on construction (including deserialization), so an anchor received from an untrusted party only needs its Self::block_commitment checked against an independently trusted value — e.g. the BLOCK_COMMITMENT word bound into a signed TransactionSummary — to be safe to execute against.

Since protocol 0.16 the signed transaction summary binds the reference block commitment, so a summary produced at one block cannot be reproduced by re-executing at another. Flows that collect signatures over a summary and execute later (e.g. multisig) capture an anchor at the block the summary was built at (crate::Client::chain_anchor_for_request), ship it with the signed data, and replay the transaction with crate::Client::execute_transaction_at so the summary — and with it the signature advice keys — reproduces exactly.

When the transaction consumes authenticated notes, the anchor’s PartialBlockchain must track each note’s creation block; crate::Client::chain_anchor_for_request captures an anchor tracking the blocks of a request’s authenticated input notes.

Implementations

impl ChainAnchor

pub fn new( header: BlockHeader, chain: PartialBlockchain, ) -> Result<ChainAnchor, ChainAnchorError>

Returns a new anchor after validating that chain is consistent with header.

Errors

• The partial blockchain’s length does not match the header’s block number.
• The partial blockchain’s peaks do not hash to the header’s chain commitment.
• The partial blockchain tracks more blocks than a transaction can reference.

pub fn block_num(&self) -> BlockNumber

Returns the number of the anchored reference block.

pub fn block_commitment(&self) -> Word

Returns the commitment of the anchored reference block.

Callers holding an anchor from an untrusted source should compare this against an independently trusted commitment (e.g. the block commitment bound into a signed transaction summary) before executing with the anchor.

pub fn header(&self) -> &BlockHeader

Returns the anchored reference block header.

pub fn partial_blockchain(&self) -> &PartialBlockchain

Returns the partial blockchain at the anchored reference block.

pub fn into_parts(self) -> (BlockHeader, PartialBlockchain)

Consumes the anchor and returns its parts.

Trait Implementations

impl Clone for ChainAnchor

fn clone(&self) -> ChainAnchor

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ChainAnchor

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

Formats the value using the given formatter.

impl Deserializable for ChainAnchor

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

where R: ByteReader,

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 Eq for ChainAnchor

impl PartialEq for ChainAnchor

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

Equality operator ==.

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

Inequality operator !=.

impl Serializable for ChainAnchor

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

where W: ByteWriter,

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

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

Serializes self into a vector of bytes.

fn get_size_hint(&self) -> usize

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

impl StructuralPartialEq for ChainAnchor