Merge pull request #2156 from alecchendev/2023-04-mpp-keysend

[rust-lightning] / lightning / src / ln / outbound_payment.rs

diff --git a/lightning/src/ln/outbound_payment.rs b/lightning/src/ln/outbound_payment.rs
index a13a618d83c4c2b0e8988f6103a1a26c2fcb2d63..2ac24baa58b3466315c2628c711f17e4f3d17d73 100644 (file)
--- a/lightning/src/ln/outbound_payment.rs
+++ b/lightning/src/ln/outbound_payment.rs
@@ -414,9 +414,9 @@ pub struct RecipientOnionFields {
        /// If you do not have one, the [`Route`] you pay over must not contain multiple paths as
        /// multi-path payments require a recipient-provided secret.
        ///
-       /// Note that for spontaneous payments most lightning nodes do not currently support MPP
-       /// receives, thus you should generally never be providing a secret here for spontaneous
-       /// payments.
+       /// Some implementations may reject spontaneous payments with payment secrets, so you may only
+       /// want to provide a secret for a spontaneous payment if MPP is needed and you know your
+       /// recipient will not reject it.
        pub payment_secret: Option<PaymentSecret>,
        /// The payment metadata serves a similar purpose as [`Self::payment_secret`] but is of
        /// arbitrary length. This gives recipients substantially more flexibility to receive
@@ -447,10 +447,13 @@ impl RecipientOnionFields {
        }
 
        /// Creates a new [`RecipientOnionFields`] with no fields. This generally does not create
-       /// payable HTLCs except for spontaneous payments, i.e. this should generally only be used for
-       /// calls to [`ChannelManager::send_spontaneous_payment`].
+       /// payable HTLCs except for single-path spontaneous payments, i.e. this should generally
+       /// only be used for calls to [`ChannelManager::send_spontaneous_payment`]. If you are sending
+       /// a spontaneous MPP this will not work as all MPP require payment secrets; you may
+       /// instead want to use [`RecipientOnionFields::secret_only`].
        ///
        /// [`ChannelManager::send_spontaneous_payment`]: super::channelmanager::ChannelManager::send_spontaneous_payment
+       /// [`RecipientOnionFields::secret_only`]: RecipientOnionFields::secret_only
        pub fn spontaneous_empty() -> Self {
                Self { payment_secret: None, payment_metadata: None }
        }