Module offer

Data structures and encoding for offer messages.

An Offer represents an “offer to be paid.” It is typically constructed by a merchant and published as a QR code to be scanned by a customer. The customer uses the offer to request an invoice from the merchant to be paid.

Example

extern crate bitcoin;
extern crate core;
extern crate lightning;

use core::convert::TryFrom;
use core::num::NonZeroU64;
use core::time::Duration;

use bitcoin::secp256k1::{KeyPair, PublicKey, Secp256k1, SecretKey};
use lightning::offers::offer::{Offer, OfferBuilder, Quantity};
use lightning::offers::parse::Bolt12ParseError;
use lightning::util::ser::{Readable, Writeable};

let secp_ctx = Secp256k1::new();
let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
let pubkey = PublicKey::from(keys);

let expiration = SystemTime::now() + Duration::from_secs(24 * 60 * 60);
let offer = OfferBuilder::new("coffee, large".to_string(), pubkey)
    .amount_msats(20_000)
    .supported_quantity(Quantity::Unbounded)
    .absolute_expiry(expiration.duration_since(SystemTime::UNIX_EPOCH).unwrap())
    .issuer("Foo Bar".to_string())
    .path(create_blinded_path())
    .path(create_another_blinded_path())
    .build()?;

// Encode as a bech32 string for use in a QR code.
let encoded_offer = offer.to_string();

// Parse from a bech32 string after scanning from a QR code.
let offer = encoded_offer.parse::<Offer>()?;

// Encode offer as raw bytes.
let mut bytes = Vec::new();
offer.write(&mut bytes).unwrap();

// Decode raw bytes into an offer.
let offer = Offer::try_from(bytes)?;

Note

If constructing an Offer for use with a ChannelManager, use ChannelManager::create_offer_builder instead of OfferBuilder::new.

Structs

DerivedMetadata

Offer::metadata will be derived.

ExplicitMetadata

Offer::metadata may be explicitly set or left empty.

Offer

An Offer is a potentially long-lived proposal for payment of a good or service.

OfferBuilder

Builds an Offer for the “offer to be paid” flow.

Enums

Amount

The minimum amount required for an item in an Offer, denominated in either bitcoin or another currency.

Quantity

Quantity of items supported by an Offer.

Traits

MetadataStrategy

Indicates how Offer::metadata may be set.

Type Aliases

CurrencyCode

An ISO 4712 three-letter currency code (e.g., USD).