Update send_onion_message API to take new OnionMessageContents enum

[rust-lightning] / lightning / src / onion_message / packet.rs

diff --git a/lightning/src/onion_message/packet.rs b/lightning/src/onion_message/packet.rs
index 1337bdb14d5d6c3bf83fcadc5beebcea8b6d70d8..8738091a94267d959b606e88d8e6ce18202fcf16 100644 (file)
--- a/lightning/src/onion_message/packet.rs
+++ b/lightning/src/onion_message/packet.rs
@@ -16,7 +16,7 @@ use ln::msgs::DecodeError;
 use ln::onion_utils;
 use super::blinded_route::{BlindedRoute, ForwardTlvs, ReceiveTlvs};
 use util::chacha20poly1305rfc::{ChaChaPolyReadAdapter, ChaChaPolyWriteAdapter};
-use util::ser::{BigSize, FixedLengthReader, LengthRead, LengthReadable, LengthReadableArgs, Readable, ReadableArgs, Writeable, Writer};
+use util::ser::{BigSize, FixedLengthReader, LengthRead, LengthReadable, LengthReadableArgs, MaybeReadableArgs, Readable, ReadableArgs, Writeable, Writer};
 
 use core::cmp;
 use io::{self, Read};
@@ -104,13 +104,41 @@ pub(super) enum Payload {
        }
 }
 
-// Coming soon:
-// enum Message {
-//     InvoiceRequest(InvoiceRequest),
-//     Invoice(Invoice),
-//     InvoiceError(InvoiceError),
-//     CustomMessage<T>,
-// }
+#[derive(Debug)]
+/// The contents of an onion message. In the context of offers, this would be the invoice, invoice
+/// request, or invoice error.
+pub enum OnionMessageContents<T> where T: CustomOnionMessageContents {
+       // Coming soon:
+       // Invoice,
+       // InvoiceRequest,
+       // InvoiceError,
+       /// A custom onion message specified by the user.
+       Custom(T),
+}
+
+impl<T> OnionMessageContents<T> where T: CustomOnionMessageContents {
+       /// Returns the type that was used to decode the message payload.
+       pub fn tlv_type(&self) -> u64 {
+               match self {
+                       &OnionMessageContents::Custom(ref msg) => msg.tlv_type(),
+               }
+       }
+}
+
+impl<T: CustomOnionMessageContents> Writeable for OnionMessageContents<T> {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+               match self {
+                       OnionMessageContents::Custom(msg) => Ok(msg.write(w)?),
+               }
+       }
+}
+
+/// The contents of a custom onion message. Must implement `MaybeReadableArgs<u64>` where the `u64`
+/// is the custom TLV type attempting to be read, and return `Ok(None)` if the TLV type is unknown.
+pub trait CustomOnionMessageContents: Writeable + MaybeReadableArgs<u64> {
+       /// Returns the TLV type identifying the message contents. MUST be >= 64.
+       fn tlv_type(&self) -> u64;
+}
 
 /// Forward control TLVs in their blinded and unblinded form.
 pub(super) enum ForwardControlTlvs {