Struct RefundBuilder

pub struct RefundBuilder<'a, T: Signing> { /* private fields */ }

Builds a Refund for the “offer for money” flow.

See module-level documentation for usage.

This is not exported to bindings users as builder patterns don’t map outside of move semantics.

Implementations

impl<'a> RefundBuilder<'a, SignOnly>

pub fn new( metadata: Vec<u8>, signing_pubkey: PublicKey, amount_msats: u64, ) -> Result<Self, Bolt12SemanticError>

Creates a new builder for a refund using the signing_pubkey for the public node id to send to if no Refund::paths are set. Otherwise, signing_pubkey may be a transient pubkey.

Additionally, sets the required (empty) Refund::description, Refund::payer_metadata, and Refund::amount_msats.

Note

If constructing a Refund for use with a ChannelManager, use ChannelManager::create_refund_builder instead of RefundBuilder::new.

impl<'a, T: Signing> RefundBuilder<'a, T>

pub fn deriving_signing_pubkey( node_id: PublicKey, expanded_key: &ExpandedKey, nonce: Nonce, secp_ctx: &'a Secp256k1<T>, amount_msats: u64, payment_id: PaymentId, ) -> Result<Self, Bolt12SemanticError>

Similar to RefundBuilder::new except, if RefundBuilder::path is called, the payer id is derived from the given ExpandedKey and nonce. This provides sender privacy by using a different payer id for each refund, assuming a different nonce is used. Otherwise, the provided node_id is used for the payer id.

Also, sets the metadata when RefundBuilder::build is called such that it can be used by Bolt12Invoice::verify_using_metadata to determine if the invoice was produced for the refund given an ExpandedKey. However, if RefundBuilder::path is called, then the metadata must be included in each BlindedMessagePath instead. In this case, use Bolt12Invoice::verify_using_payer_data.

The payment_id is encrypted in the metadata and should be unique. This ensures that only one invoice will be paid for the refund and that payments can be uniquely identified.

pub fn description(self, description: String) -> Self

Sets the Refund::description.

Successive calls to this method will override the previous setting.

pub fn absolute_expiry(self, absolute_expiry: Duration) -> Self

Sets the Refund::absolute_expiry as seconds since the Unix epoch. Any expiry that has already passed is valid and can be checked for using Refund::is_expired.

Successive calls to this method will override the previous setting.

pub fn issuer(self, issuer: String) -> Self

Sets the Refund::issuer.

Successive calls to this method will override the previous setting.

pub fn path(self, path: BlindedMessagePath) -> Self

Adds a blinded path to Refund::paths. Must include at least one path if only connected by private channels or if Refund::payer_signing_pubkey is not a public node id.

Successive calls to this method will add another blinded path. Caller is responsible for not adding duplicate paths.

pub fn chain(self, network: Network) -> Self

Sets the Refund::chain of the given Network for paying an invoice. If not called, Network::Bitcoin is assumed.

Successive calls to this method will override the previous setting.

pub fn quantity(self, quantity: u64) -> Self

Sets Refund::quantity of items. This is purely for informational purposes. It is useful when the refund pertains to a Bolt12Invoice that paid for more than one item from an Offer as specified by InvoiceRequest::quantity.

Successive calls to this method will override the previous setting.

pub fn payer_note(self, payer_note: String) -> Self

Sets the Refund::payer_note.

Successive calls to this method will override the previous setting.

pub fn build(self) -> Result<Refund, Bolt12SemanticError>

Builds a Refund after checking for valid semantics.