Add Features feature to invoices.

[rust-lightning] / lightning-invoice / src / lib.rs

diff --git a/lightning-invoice/src/lib.rs b/lightning-invoice/src/lib.rs
index 315cf641c8ec80a953ae25fc654be5eba9951888..3d75d4d65dc057c148d11886ae03a702da9205ea 100644 (file)
--- a/lightning-invoice/src/lib.rs
+++ b/lightning-invoice/src/lib.rs
@@ -24,6 +24,7 @@ extern crate secp256k1;
 use bech32::u5;
 use bitcoin_hashes::Hash;
 use bitcoin_hashes::sha256;
+use lightning::ln::features::InvoiceFeatures;
 #[cfg(any(doc, test))]
 use lightning::routing::network_graph::RoutingFees;
 use lightning::routing::router::RouteHintHop;
@@ -329,6 +330,7 @@ pub enum TaggedField {
        Fallback(Fallback),
        Route(RouteHint),
        PaymentSecret(PaymentSecret),
+       Features(InvoiceFeatures),
 }
 
 /// SHA-256 hash
@@ -401,6 +403,7 @@ pub mod constants {
        pub const TAG_FALLBACK: u8 = 9;
        pub const TAG_ROUTE: u8 = 3;
        pub const TAG_PAYMENT_SECRET: u8 = 16;
+       pub const TAG_FEATURES: u8 = 5;
 }
 
 impl InvoiceBuilder<tb::False, tb::False, tb::False> {
@@ -491,6 +494,13 @@ impl<D: tb::Bool, H: tb::Bool, T: tb::Bool> InvoiceBuilder<D, H, T> {
                }
                self
        }
+
+       /// Adds a features field which indicates the set of supported protocol extensions which the
+       /// origin node supports.
+       pub fn features(mut self, features: InvoiceFeatures) -> Self {
+               self.tagged_fields.push(TaggedField::Features(features));
+               self
+       }
 }
 
 impl<D: tb::Bool, H: tb::Bool> InvoiceBuilder<D, H, tb::True> {
@@ -810,6 +820,10 @@ impl RawInvoice {
                find_extract!(self.known_tagged_fields(), TaggedField::PaymentSecret(ref x), x)
        }
 
+       pub fn features(&self) -> Option<&InvoiceFeatures> {
+               find_extract!(self.known_tagged_fields(), TaggedField::Features(ref x), x)
+       }
+
        pub fn fallbacks(&self) -> Vec<&Fallback> {
                self.known_tagged_fields().filter_map(|tf| match tf {
                        &TaggedField::Fallback(ref f) => Some(f),
@@ -997,6 +1011,11 @@ impl Invoice {
                self.signed_invoice.payment_secret()
        }
 
+       /// Get the invoice features if they were included in the invoice
+       pub fn features(&self) -> Option<&InvoiceFeatures> {
+               self.signed_invoice.features()
+       }
+
        /// Recover the payee's public key (only to be used if none was included in the invoice)
        pub fn recover_payee_pub_key(&self) -> PublicKey {
                self.signed_invoice.recover_payee_pub_key().expect("was checked by constructor").0
@@ -1054,6 +1073,7 @@ impl TaggedField {
                        TaggedField::Fallback(_) => constants::TAG_FALLBACK,
                        TaggedField::Route(_) => constants::TAG_ROUTE,
                        TaggedField::PaymentSecret(_) => constants::TAG_PAYMENT_SECRET,
+                       TaggedField::Features(_) => constants::TAG_FEATURES,
                };
 
                u5::try_from_u8(tag).expect("all tags defined are <32")