Add SendingParameters struct for customizable payments

bindings/kotlin/ldk-node-jvm/lib/src/test/kotlin/org/lightningdevkit/ldknode/LibraryTest.kt

@@ -224,7 +224,7 @@ class LibraryTest {
 
  val invoice = node2.bolt11Payment().receive(2500000u, "asdf", 9217u)
 
- node1.bolt11Payment().send(invoice)
+ node1.bolt11Payment().send(invoice, null)
 
  val paymentSuccessfulEvent = node1.waitNextEvent()
  println("Got event: $paymentSuccessfulEvent")

bindings/ldk_node.udl

@@ -16,6 +16,7 @@ dictionary Config {
 	u64 probing_liquidity_limit_multiplier;
 	LogLevel log_level;
 	AnchorChannelsConfig? anchor_channels_config;
+	SendingParameters? sending_parameters_config;
 };
 
 dictionary AnchorChannelsConfig {
@@ -93,9 +94,9 @@ interface Node {
 
 interface Bolt11Payment {
 	[Throws=NodeError]
-	PaymentId send([ByRef]Bolt11Invoice invoice);
+	PaymentId send([ByRef]Bolt11Invoice invoice, SendingParameters? sending_parameters);
 	[Throws=NodeError]
-	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat);
+	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes([ByRef]Bolt11Invoice invoice);
 	[Throws=NodeError]
@@ -135,7 +136,7 @@ interface Bolt12Payment {
 
 interface SpontaneousPayment {
 	[Throws=NodeError]
-	PaymentId send(u64 amount_msat, PublicKey node_id);
+	PaymentId send(u64 amount_msat, PublicKey node_id, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes(u64 amount_msat, PublicKey node_id);
 };
@@ -319,6 +320,13 @@ dictionary PaymentDetails {
 	u64 latest_update_timestamp;
 };
 
+dictionary SendingParameters {
+ u64? max_total_routing_fee_msat;
+ u32? max_total_cltv_expiry_delta;
+ u8? max_path_count;
+ u8? max_channel_saturation_power_of_half;
+};
+
 [NonExhaustive]
 enum Network {
 	"Bitcoin",

src/config.rs

@@ -1,5 +1,7 @@
 use std::time::Duration;
 
+use crate::payment::SendingParameters;
+
 use lightning::ln::msgs::SocketAddress;
 use lightning::util::config::UserConfig;
 use lightning::util::logger::Level as LogLevel;
@@ -86,6 +88,7 @@ pub(crate) const WALLET_KEYS_SEED_LEN: usize = 64;
 /// | `probing_liquidity_limit_multiplier` | 3 |
 /// | `log_level` | Debug |
 /// | `anchor_channels_config` | Some(..) |
+/// | `sending_parameters_config` | None |
 ///
 /// See [`AnchorChannelsConfig`] for more information on its respective default values.
 ///
@@ -147,6 +150,12 @@ pub struct Config {
 	/// closure. We *will* however still try to get the Anchor spending transactions confirmed
 	/// on-chain with the funds available.
 	pub anchor_channels_config: Option<AnchorChannelsConfig>,
+
+	/// Configuration options for payment routing and pathfinding.
+	///
+	/// Setting the `SendingParameters` provides flexibility to customize how payments are routed,
+	/// including setting limits on routing fees, CLTV expiry, and channel utilization.
+	pub sending_parameters_config: Option<SendingParameters>,
 }
 
 impl Default for Config {
@@ -164,6 +173,7 @@ impl Default for Config {
  probing_liquidity_limit_multiplier: DEFAULT_PROBING_LIQUIDITY_LIMIT_MULTIPLIER,
  log_level: DEFAULT_LOG_LEVEL,
  anchor_channels_config: Some(AnchorChannelsConfig::default()),
+ sending_parameters_config: None,
  }
 	}
 }

src/lib.rs

@@ -56,7 +56,7 @@
 //! node.event_handled();
 //!
 //! let invoice = Bolt11Invoice::from_str("INVOICE_STR").unwrap();
-//! node.bolt11_payment().send(&invoice).unwrap();
+//! node.bolt11_payment().send(&invoice, None).unwrap();
 //!
 //! node.stop().unwrap();
 //! }

src/payment/bolt11.rs

@@ -11,6 +11,7 @@ use crate::payment::store::{
 	LSPFeeLimits, PaymentDetails, PaymentDetailsUpdate, PaymentDirection, PaymentKind,
 	PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::peer_store::{PeerInfo, PeerStore};
 use crate::types::{ChannelManager, KeysManager};
 
@@ -69,13 +70,20 @@ impl Bolt11Payment {
 	}
 
 	/// Send a payment given an invoice.
-	pub fn send(&self, invoice: &Bolt11Invoice) -> Result<PaymentId, Error> {
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, invoice: &Bolt11Invoice, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
  }
 
- let (payment_hash, recipient_onion, route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
+ let (payment_hash, recipient_onion, mut route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
  log_error!(self.logger, "Failed to send payment due to the given invoice being \"zero-amount\". Please use send_using_amount instead.");
  Error::InvalidInvoice
  })?;
@@ -90,6 +98,40 @@ impl Bolt11Payment {
  }
  }
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let payment_secret = Some(*invoice.payment_secret());
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
 
@@ -148,14 +190,20 @@ impl Bolt11Payment {
  }
 	}
 
-	/// Send a payment given an invoice and an amount in millisatoshi.
+	/// Send a payment given an invoice and an amount in millisatoshis.
 	///
 	/// This will fail if the amount given is less than the value required by the given invoice.
 	///
 	/// This can be used to pay a so-called "zero-amount" invoice, i.e., an invoice that leaves the
 	/// amount paid to be determined by the user.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
 	pub fn send_using_amount(
  &self, invoice: &Bolt11Invoice, amount_msat: u64,
+ sending_parameters: Option<SendingParameters>,
 	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
@@ -196,9 +244,43 @@ impl Bolt11Payment {
  .with_bolt11_features(features.clone())
  .map_err(|_| Error::InvalidInvoice)?;
  }
- let route_params =
+ let mut route_params =
  RouteParameters::from_payment_params_and_value(payment_params, amount_msat);
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
  let recipient_fields = RecipientOnionFields::secret_only(*payment_secret);
 

src/payment/mod.rs

@@ -13,3 +13,52 @@ pub use onchain::OnchainPayment;
 pub use spontaneous::SpontaneousPayment;
 pub use store::{LSPFeeLimits, PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus};
 pub use unified_qr::{QrPaymentResult, UnifiedQrPayment};
+
+/// Represents information used to route a payment.
+#[derive(Clone, Debug, PartialEq)]
+pub struct SendingParameters {
+	/// The maximum total fees, in millisatoshi, that may accrue during route finding.
+	///
+	/// This limit also applies to the total fees that may arise while retrying failed payment
+	/// paths.
+	///
+	/// Note that values below a few sats may result in some paths being spuriously ignored.
+	pub max_total_routing_fee_msat: Option<u64>,
+
+	/// The maximum total CLTV delta we accept for the route.
+	///
+	/// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
+	///
+	/// [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`]: lightning::routing::router::DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA
+	pub max_total_cltv_expiry_delta: Option<u32>,
+
+	/// The maximum number of paths that may be used by (MPP) payments.
+	///
+	/// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
+	///
+	/// [`DEFAULT_MAX_PATH_COUNT`]: lightning::routing::router::DEFAULT_MAX_PATH_COUNT
+	pub max_path_count: Option<u8>,
+
+	/// Selects the maximum share of a channel's total capacity which will be sent over a channel,
+	/// as a power of 1/2.
+	///
+	/// A higher value prefers to send the payment using more MPP parts whereas
+	/// a lower value prefers to send larger MPP parts, potentially saturating channels and
+	/// increasing failure probability for those paths.
+	///
+	/// Note that this restriction will be relaxed during pathfinding after paths which meet this
+	/// restriction have been found. While paths which meet this criteria will be searched for, it
+	/// is ultimately up to the scorer to select them over other paths.
+	///
+	/// Examples:
+	///
+	/// | Value | Max Proportion of Channel Capacity Used |
+	/// |-------|-----------------------------------------|
+	/// | 0 | Up to 100% of the channel’s capacity |
+	/// | 1 | Up to 50% of the channel’s capacity |
+	/// | 2 | Up to 25% of the channel’s capacity |
+	/// | 3 | Up to 12.5% of the channel’s capacity |
+	///
+	/// Default value: 2
+	pub max_channel_saturation_power_of_half: Option<u8>,
+}

src/payment/spontaneous.rs

@@ -6,6 +6,7 @@ use crate::logger::{log_error, log_info, FilesystemLogger, Logger};
 use crate::payment::store::{
 	PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::types::{ChannelManager, KeysManager};
 
 use lightning::ln::channelmanager::{PaymentId, RecipientOnionFields, Retry, RetryableSendFailure};
@@ -41,8 +42,15 @@ impl SpontaneousPayment {
  Self { runtime, channel_manager, keys_manager, payment_store, config, logger }
 	}
 
-	/// Send a spontaneous, aka. "keysend", payment
-	pub fn send(&self, amount_msat: u64, node_id: PublicKey) -> Result<PaymentId, Error> {
+	/// Send a spontaneous aka. "keysend", payment.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, amount_msat: u64, node_id: PublicKey, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
@@ -61,10 +69,45 @@ impl SpontaneousPayment {
  }
  }
 
- let route_params = RouteParameters::from_payment_params_and_value(
+ let mut route_params = RouteParameters::from_payment_params_and_value(
  PaymentParameters::from_node_id(node_id, self.config.default_cltv_expiry_delta),
  amount_msat,
  );
+
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let recipient_fields = RecipientOnionFields::spontaneous_empty();
 
  match self.channel_manager.send_spontaneous_payment_with_retry(

src/payment/unified_qr.rs

@@ -143,7 +143,7 @@ impl UnifiedQrPayment {
  }
 
  if let Some(invoice) = uri_network_checked.extras.bolt11_invoice {
- match self.bolt11_invoice.send(&invoice) {
+ match self.bolt11_invoice.send(&invoice, None) {
  Ok(payment_id) => return Ok(QrPaymentResult::Bolt11 { payment_id }),
  Err(e) => log_error!(self.logger, "Failed to send BOLT11 invoice: {:?}. This is part of a unified QR code payment. Falling back to the on-chain transaction.", e),
  }

src/uniffi_types.rs

@@ -5,7 +5,7 @@
 
 pub use crate::graph::{ChannelInfo, ChannelUpdateInfo, NodeAnnouncementInfo, NodeInfo};
 pub use crate::payment::store::{LSPFeeLimits, PaymentDirection, PaymentKind, PaymentStatus};
-pub use crate::payment::QrPaymentResult;
+pub use crate::payment::{QrPaymentResult, SendingParameters};
 
 pub use lightning::events::{ClosureReason, PaymentFailureReason};
 pub use lightning::ln::{ChannelId, PaymentHash, PaymentPreimage, PaymentSecret};

bindings/kotlin/ldk-node-jvm/lib/src/test/kotlin/org/lightningdevkit/ldknode/LibraryTest.kt

@@ -224,7 +224,7 @@ class LibraryTest {
 
  val invoice = node2.bolt11Payment().receive(2500000u, "asdf", 9217u)
 
- node1.bolt11Payment().send(invoice)
+ node1.bolt11Payment().send(invoice, null)
 
  val paymentSuccessfulEvent = node1.waitNextEvent()
  println("Got event: $paymentSuccessfulEvent")

bindings/ldk_node.udl

@@ -16,6 +16,7 @@ dictionary Config {
 	u64 probing_liquidity_limit_multiplier;
 	LogLevel log_level;
 	AnchorChannelsConfig? anchor_channels_config;
+	SendingParameters? sending_parameters_config;
 };
 
 dictionary AnchorChannelsConfig {
@@ -93,9 +94,9 @@ interface Node {
 
 interface Bolt11Payment {
 	[Throws=NodeError]
-	PaymentId send([ByRef]Bolt11Invoice invoice);
+	PaymentId send([ByRef]Bolt11Invoice invoice, SendingParameters? sending_parameters);
 	[Throws=NodeError]
-	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat);
+	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes([ByRef]Bolt11Invoice invoice);
 	[Throws=NodeError]
@@ -135,7 +136,7 @@ interface Bolt12Payment {
 
 interface SpontaneousPayment {
 	[Throws=NodeError]
-	PaymentId send(u64 amount_msat, PublicKey node_id);
+	PaymentId send(u64 amount_msat, PublicKey node_id, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes(u64 amount_msat, PublicKey node_id);
 };
@@ -319,6 +320,13 @@ dictionary PaymentDetails {
 	u64 latest_update_timestamp;
 };
 
+dictionary SendingParameters {
+ u64? max_total_routing_fee_msat;
+ u32? max_total_cltv_expiry_delta;
+ u8? max_path_count;
+ u8? max_channel_saturation_power_of_half;
+};
+
 [NonExhaustive]
 enum Network {
 	"Bitcoin",

src/config.rs

@@ -1,5 +1,7 @@
 use std::time::Duration;
 
+use crate::payment::SendingParameters;
+
 use lightning::ln::msgs::SocketAddress;
 use lightning::util::config::UserConfig;
 use lightning::util::logger::Level as LogLevel;
@@ -86,6 +88,7 @@ pub(crate) const WALLET_KEYS_SEED_LEN: usize = 64;
 /// | `probing_liquidity_limit_multiplier` | 3 |
 /// | `log_level` | Debug |
 /// | `anchor_channels_config` | Some(..) |
+/// | `sending_parameters_config` | None |
 ///
 /// See [`AnchorChannelsConfig`] for more information on its respective default values.
 ///
@@ -147,6 +150,12 @@ pub struct Config {
 	/// closure. We *will* however still try to get the Anchor spending transactions confirmed
 	/// on-chain with the funds available.
 	pub anchor_channels_config: Option<AnchorChannelsConfig>,
+
+	/// Configuration options for payment routing and pathfinding.
+	///
+	/// Setting the `SendingParameters` provides flexibility to customize how payments are routed,
+	/// including setting limits on routing fees, CLTV expiry, and channel utilization.
+	pub sending_parameters_config: Option<SendingParameters>,
 }
 
 impl Default for Config {
@@ -164,6 +173,7 @@ impl Default for Config {
  probing_liquidity_limit_multiplier: DEFAULT_PROBING_LIQUIDITY_LIMIT_MULTIPLIER,
  log_level: DEFAULT_LOG_LEVEL,
  anchor_channels_config: Some(AnchorChannelsConfig::default()),
+ sending_parameters_config: None,
  }
 	}
 }

src/lib.rs

@@ -56,7 +56,7 @@
 //! node.event_handled();
 //!
 //! let invoice = Bolt11Invoice::from_str("INVOICE_STR").unwrap();
-//! node.bolt11_payment().send(&invoice).unwrap();
+//! node.bolt11_payment().send(&invoice, None).unwrap();
 //!
 //! node.stop().unwrap();
 //! }

src/payment/bolt11.rs

@@ -11,6 +11,7 @@ use crate::payment::store::{
 	LSPFeeLimits, PaymentDetails, PaymentDetailsUpdate, PaymentDirection, PaymentKind,
 	PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::peer_store::{PeerInfo, PeerStore};
 use crate::types::{ChannelManager, KeysManager};
 
@@ -69,13 +70,20 @@ impl Bolt11Payment {
 	}
 
 	/// Send a payment given an invoice.
-	pub fn send(&self, invoice: &Bolt11Invoice) -> Result<PaymentId, Error> {
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, invoice: &Bolt11Invoice, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
  }
 
- let (payment_hash, recipient_onion, route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
+ let (payment_hash, recipient_onion, mut route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
  log_error!(self.logger, "Failed to send payment due to the given invoice being \"zero-amount\". Please use send_using_amount instead.");
  Error::InvalidInvoice
  })?;
@@ -90,6 +98,40 @@ impl Bolt11Payment {
  }
  }
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let payment_secret = Some(*invoice.payment_secret());
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
 
@@ -148,14 +190,20 @@ impl Bolt11Payment {
  }
 	}
 
-	/// Send a payment given an invoice and an amount in millisatoshi.
+	/// Send a payment given an invoice and an amount in millisatoshis.
 	///
 	/// This will fail if the amount given is less than the value required by the given invoice.
 	///
 	/// This can be used to pay a so-called "zero-amount" invoice, i.e., an invoice that leaves the
 	/// amount paid to be determined by the user.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
 	pub fn send_using_amount(
  &self, invoice: &Bolt11Invoice, amount_msat: u64,
+ sending_parameters: Option<SendingParameters>,
 	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
@@ -196,9 +244,43 @@ impl Bolt11Payment {
  .with_bolt11_features(features.clone())
  .map_err(|_| Error::InvalidInvoice)?;
  }
- let route_params =
+ let mut route_params =
  RouteParameters::from_payment_params_and_value(payment_params, amount_msat);
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
  let recipient_fields = RecipientOnionFields::secret_only(*payment_secret);
 

src/payment/mod.rs

@@ -13,3 +13,52 @@ pub use onchain::OnchainPayment;
 pub use spontaneous::SpontaneousPayment;
 pub use store::{LSPFeeLimits, PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus};
 pub use unified_qr::{QrPaymentResult, UnifiedQrPayment};
+
+/// Represents information used to route a payment.
+#[derive(Clone, Debug, PartialEq)]
+pub struct SendingParameters {
+	/// The maximum total fees, in millisatoshi, that may accrue during route finding.
+	///
+	/// This limit also applies to the total fees that may arise while retrying failed payment
+	/// paths.
+	///
+	/// Note that values below a few sats may result in some paths being spuriously ignored.
+	pub max_total_routing_fee_msat: Option<u64>,
+
+	/// The maximum total CLTV delta we accept for the route.
+	///
+	/// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
+	///
+	/// [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`]: lightning::routing::router::DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA
+	pub max_total_cltv_expiry_delta: Option<u32>,
+
+	/// The maximum number of paths that may be used by (MPP) payments.
+	///
+	/// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
+	///
+	/// [`DEFAULT_MAX_PATH_COUNT`]: lightning::routing::router::DEFAULT_MAX_PATH_COUNT
+	pub max_path_count: Option<u8>,
+
+	/// Selects the maximum share of a channel's total capacity which will be sent over a channel,
+	/// as a power of 1/2.
+	///
+	/// A higher value prefers to send the payment using more MPP parts whereas
+	/// a lower value prefers to send larger MPP parts, potentially saturating channels and
+	/// increasing failure probability for those paths.
+	///
+	/// Note that this restriction will be relaxed during pathfinding after paths which meet this
+	/// restriction have been found. While paths which meet this criteria will be searched for, it
+	/// is ultimately up to the scorer to select them over other paths.
+	///
+	/// Examples:
+	///
+	/// | Value | Max Proportion of Channel Capacity Used |
+	/// |-------|-----------------------------------------|
+	/// | 0 | Up to 100% of the channel’s capacity |
+	/// | 1 | Up to 50% of the channel’s capacity |
+	/// | 2 | Up to 25% of the channel’s capacity |
+	/// | 3 | Up to 12.5% of the channel’s capacity |
+	///
+	/// Default value: 2
+	pub max_channel_saturation_power_of_half: Option<u8>,
+}

src/payment/spontaneous.rs

@@ -6,6 +6,7 @@ use crate::logger::{log_error, log_info, FilesystemLogger, Logger};
 use crate::payment::store::{
 	PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::types::{ChannelManager, KeysManager};
 
 use lightning::ln::channelmanager::{PaymentId, RecipientOnionFields, Retry, RetryableSendFailure};
@@ -41,8 +42,15 @@ impl SpontaneousPayment {
  Self { runtime, channel_manager, keys_manager, payment_store, config, logger }
 	}
 
-	/// Send a spontaneous, aka. "keysend", payment
-	pub fn send(&self, amount_msat: u64, node_id: PublicKey) -> Result<PaymentId, Error> {
+	/// Send a spontaneous aka. "keysend", payment.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, amount_msat: u64, node_id: PublicKey, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
@@ -61,10 +69,45 @@ impl SpontaneousPayment {
  }
  }
 
- let route_params = RouteParameters::from_payment_params_and_value(
+ let mut route_params = RouteParameters::from_payment_params_and_value(
  PaymentParameters::from_node_id(node_id, self.config.default_cltv_expiry_delta),
  amount_msat,
  );
+
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let recipient_fields = RecipientOnionFields::spontaneous_empty();
 
  match self.channel_manager.send_spontaneous_payment_with_retry(

src/payment/unified_qr.rs

@@ -143,7 +143,7 @@ impl UnifiedQrPayment {
  }
 
  if let Some(invoice) = uri_network_checked.extras.bolt11_invoice {
- match self.bolt11_invoice.send(&invoice) {
+ match self.bolt11_invoice.send(&invoice, None) {
  Ok(payment_id) => return Ok(QrPaymentResult::Bolt11 { payment_id }),
  Err(e) => log_error!(self.logger, "Failed to send BOLT11 invoice: {:?}. This is part of a unified QR code payment. Falling back to the on-chain transaction.", e),
  }

src/uniffi_types.rs

@@ -5,7 +5,7 @@
 
 pub use crate::graph::{ChannelInfo, ChannelUpdateInfo, NodeAnnouncementInfo, NodeInfo};
 pub use crate::payment::store::{LSPFeeLimits, PaymentDirection, PaymentKind, PaymentStatus};
-pub use crate::payment::QrPaymentResult;
+pub use crate::payment::{QrPaymentResult, SendingParameters};
 
 pub use lightning::events::{ClosureReason, PaymentFailureReason};
 pub use lightning::ln::{ChannelId, PaymentHash, PaymentPreimage, PaymentSecret};

bindings/kotlin/ldk-node-jvm/lib/src/test/kotlin/org/lightningdevkit/ldknode/LibraryTest.kt

@@ -224,7 +224,7 @@ class LibraryTest {
 
  val invoice = node2.bolt11Payment().receive(2500000u, "asdf", 9217u)
 
- node1.bolt11Payment().send(invoice)
+ node1.bolt11Payment().send(invoice, null)
 
  val paymentSuccessfulEvent = node1.waitNextEvent()
  println("Got event: $paymentSuccessfulEvent")

bindings/ldk_node.udl

@@ -16,6 +16,7 @@ dictionary Config {
 	u64 probing_liquidity_limit_multiplier;
 	LogLevel log_level;
 	AnchorChannelsConfig? anchor_channels_config;
+	SendingParameters? sending_parameters_config;
 };
 
 dictionary AnchorChannelsConfig {
@@ -93,9 +94,9 @@ interface Node {
 
 interface Bolt11Payment {
 	[Throws=NodeError]
-	PaymentId send([ByRef]Bolt11Invoice invoice);
+	PaymentId send([ByRef]Bolt11Invoice invoice, SendingParameters? sending_parameters);
 	[Throws=NodeError]
-	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat);
+	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes([ByRef]Bolt11Invoice invoice);
 	[Throws=NodeError]
@@ -135,7 +136,7 @@ interface Bolt12Payment {
 
 interface SpontaneousPayment {
 	[Throws=NodeError]
-	PaymentId send(u64 amount_msat, PublicKey node_id);
+	PaymentId send(u64 amount_msat, PublicKey node_id, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes(u64 amount_msat, PublicKey node_id);
 };
@@ -319,6 +320,13 @@ dictionary PaymentDetails {
 	u64 latest_update_timestamp;
 };
 
+dictionary SendingParameters {
+ u64? max_total_routing_fee_msat;
+ u32? max_total_cltv_expiry_delta;
+ u8? max_path_count;
+ u8? max_channel_saturation_power_of_half;
+};
+
 [NonExhaustive]
 enum Network {
 	"Bitcoin",

src/config.rs

@@ -1,5 +1,7 @@
 use std::time::Duration;
 
+use crate::payment::SendingParameters;
+
 use lightning::ln::msgs::SocketAddress;
 use lightning::util::config::UserConfig;
 use lightning::util::logger::Level as LogLevel;
@@ -86,6 +88,7 @@ pub(crate) const WALLET_KEYS_SEED_LEN: usize = 64;
 /// | `probing_liquidity_limit_multiplier` | 3 |
 /// | `log_level` | Debug |
 /// | `anchor_channels_config` | Some(..) |
+/// | `sending_parameters_config` | None |
 ///
 /// See [`AnchorChannelsConfig`] for more information on its respective default values.
 ///
@@ -147,6 +150,12 @@ pub struct Config {
 	/// closure. We *will* however still try to get the Anchor spending transactions confirmed
 	/// on-chain with the funds available.
 	pub anchor_channels_config: Option<AnchorChannelsConfig>,
+
+	/// Configuration options for payment routing and pathfinding.
+	///
+	/// Setting the `SendingParameters` provides flexibility to customize how payments are routed,
+	/// including setting limits on routing fees, CLTV expiry, and channel utilization.
+	pub sending_parameters_config: Option<SendingParameters>,
 }
 
 impl Default for Config {
@@ -164,6 +173,7 @@ impl Default for Config {
  probing_liquidity_limit_multiplier: DEFAULT_PROBING_LIQUIDITY_LIMIT_MULTIPLIER,
  log_level: DEFAULT_LOG_LEVEL,
  anchor_channels_config: Some(AnchorChannelsConfig::default()),
+ sending_parameters_config: None,
  }
 	}
 }

src/lib.rs

@@ -56,7 +56,7 @@
 //! node.event_handled();
 //!
 //! let invoice = Bolt11Invoice::from_str("INVOICE_STR").unwrap();
-//! node.bolt11_payment().send(&invoice).unwrap();
+//! node.bolt11_payment().send(&invoice, None).unwrap();
 //!
 //! node.stop().unwrap();
 //! }

src/payment/bolt11.rs

@@ -11,6 +11,7 @@ use crate::payment::store::{
 	LSPFeeLimits, PaymentDetails, PaymentDetailsUpdate, PaymentDirection, PaymentKind,
 	PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::peer_store::{PeerInfo, PeerStore};
 use crate::types::{ChannelManager, KeysManager};
 
@@ -69,13 +70,20 @@ impl Bolt11Payment {
 	}
 
 	/// Send a payment given an invoice.
-	pub fn send(&self, invoice: &Bolt11Invoice) -> Result<PaymentId, Error> {
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, invoice: &Bolt11Invoice, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
  }
 
- let (payment_hash, recipient_onion, route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
+ let (payment_hash, recipient_onion, mut route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
  log_error!(self.logger, "Failed to send payment due to the given invoice being \"zero-amount\". Please use send_using_amount instead.");
  Error::InvalidInvoice
  })?;
@@ -90,6 +98,40 @@ impl Bolt11Payment {
  }
  }
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let payment_secret = Some(*invoice.payment_secret());
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
 
@@ -148,14 +190,20 @@ impl Bolt11Payment {
  }
 	}
 
-	/// Send a payment given an invoice and an amount in millisatoshi.
+	/// Send a payment given an invoice and an amount in millisatoshis.
 	///
 	/// This will fail if the amount given is less than the value required by the given invoice.
 	///
 	/// This can be used to pay a so-called "zero-amount" invoice, i.e., an invoice that leaves the
 	/// amount paid to be determined by the user.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
 	pub fn send_using_amount(
  &self, invoice: &Bolt11Invoice, amount_msat: u64,
+ sending_parameters: Option<SendingParameters>,
 	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
@@ -196,9 +244,43 @@ impl Bolt11Payment {
  .with_bolt11_features(features.clone())
  .map_err(|_| Error::InvalidInvoice)?;
  }
- let route_params =
+ let mut route_params =
  RouteParameters::from_payment_params_and_value(payment_params, amount_msat);
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
  let recipient_fields = RecipientOnionFields::secret_only(*payment_secret);
 

src/payment/mod.rs

@@ -13,3 +13,52 @@ pub use onchain::OnchainPayment;
 pub use spontaneous::SpontaneousPayment;
 pub use store::{LSPFeeLimits, PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus};
 pub use unified_qr::{QrPaymentResult, UnifiedQrPayment};
+
+/// Represents information used to route a payment.
+#[derive(Clone, Debug, PartialEq)]
+pub struct SendingParameters {
+	/// The maximum total fees, in millisatoshi, that may accrue during route finding.
+	///
+	/// This limit also applies to the total fees that may arise while retrying failed payment
+	/// paths.
+	///
+	/// Note that values below a few sats may result in some paths being spuriously ignored.
+	pub max_total_routing_fee_msat: Option<u64>,
+
+	/// The maximum total CLTV delta we accept for the route.
+	///
+	/// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
+	///
+	/// [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`]: lightning::routing::router::DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA
+	pub max_total_cltv_expiry_delta: Option<u32>,
+
+	/// The maximum number of paths that may be used by (MPP) payments.
+	///
+	/// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
+	///
+	/// [`DEFAULT_MAX_PATH_COUNT`]: lightning::routing::router::DEFAULT_MAX_PATH_COUNT
+	pub max_path_count: Option<u8>,
+
+	/// Selects the maximum share of a channel's total capacity which will be sent over a channel,
+	/// as a power of 1/2.
+	///
+	/// A higher value prefers to send the payment using more MPP parts whereas
+	/// a lower value prefers to send larger MPP parts, potentially saturating channels and
+	/// increasing failure probability for those paths.
+	///
+	/// Note that this restriction will be relaxed during pathfinding after paths which meet this
+	/// restriction have been found. While paths which meet this criteria will be searched for, it
+	/// is ultimately up to the scorer to select them over other paths.
+	///
+	/// Examples:
+	///
+	/// | Value | Max Proportion of Channel Capacity Used |
+	/// |-------|-----------------------------------------|
+	/// | 0 | Up to 100% of the channel’s capacity |
+	/// | 1 | Up to 50% of the channel’s capacity |
+	/// | 2 | Up to 25% of the channel’s capacity |
+	/// | 3 | Up to 12.5% of the channel’s capacity |
+	///
+	/// Default value: 2
+	pub max_channel_saturation_power_of_half: Option<u8>,
+}

src/payment/spontaneous.rs

@@ -6,6 +6,7 @@ use crate::logger::{log_error, log_info, FilesystemLogger, Logger};
 use crate::payment::store::{
 	PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::types::{ChannelManager, KeysManager};
 
 use lightning::ln::channelmanager::{PaymentId, RecipientOnionFields, Retry, RetryableSendFailure};
@@ -41,8 +42,15 @@ impl SpontaneousPayment {
  Self { runtime, channel_manager, keys_manager, payment_store, config, logger }
 	}
 
-	/// Send a spontaneous, aka. "keysend", payment
-	pub fn send(&self, amount_msat: u64, node_id: PublicKey) -> Result<PaymentId, Error> {
+	/// Send a spontaneous aka. "keysend", payment.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, amount_msat: u64, node_id: PublicKey, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
@@ -61,10 +69,45 @@ impl SpontaneousPayment {
  }
  }
 
- let route_params = RouteParameters::from_payment_params_and_value(
+ let mut route_params = RouteParameters::from_payment_params_and_value(
  PaymentParameters::from_node_id(node_id, self.config.default_cltv_expiry_delta),
  amount_msat,
  );
+
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let recipient_fields = RecipientOnionFields::spontaneous_empty();
 
  match self.channel_manager.send_spontaneous_payment_with_retry(

src/payment/unified_qr.rs

@@ -143,7 +143,7 @@ impl UnifiedQrPayment {
  }
 
  if let Some(invoice) = uri_network_checked.extras.bolt11_invoice {
- match self.bolt11_invoice.send(&invoice) {
+ match self.bolt11_invoice.send(&invoice, None) {
  Ok(payment_id) => return Ok(QrPaymentResult::Bolt11 { payment_id }),
  Err(e) => log_error!(self.logger, "Failed to send BOLT11 invoice: {:?}. This is part of a unified QR code payment. Falling back to the on-chain transaction.", e),
  }

src/uniffi_types.rs

@@ -5,7 +5,7 @@
 
 pub use crate::graph::{ChannelInfo, ChannelUpdateInfo, NodeAnnouncementInfo, NodeInfo};
 pub use crate::payment::store::{LSPFeeLimits, PaymentDirection, PaymentKind, PaymentStatus};
-pub use crate::payment::QrPaymentResult;
+pub use crate::payment::{QrPaymentResult, SendingParameters};
 
 pub use lightning::events::{ClosureReason, PaymentFailureReason};
 pub use lightning::ln::{ChannelId, PaymentHash, PaymentPreimage, PaymentSecret};

bindings/kotlin/ldk-node-jvm/lib/src/test/kotlin/org/lightningdevkit/ldknode/LibraryTest.kt

@@ -224,7 +224,7 @@ class LibraryTest {
 
  val invoice = node2.bolt11Payment().receive(2500000u, "asdf", 9217u)
 
- node1.bolt11Payment().send(invoice)
+ node1.bolt11Payment().send(invoice, null)
 
  val paymentSuccessfulEvent = node1.waitNextEvent()
  println("Got event: $paymentSuccessfulEvent")

bindings/ldk_node.udl

@@ -16,6 +16,7 @@ dictionary Config {
 	u64 probing_liquidity_limit_multiplier;
 	LogLevel log_level;
 	AnchorChannelsConfig? anchor_channels_config;
+	SendingParameters? sending_parameters_config;
 };
 
 dictionary AnchorChannelsConfig {
@@ -93,9 +94,9 @@ interface Node {
 
 interface Bolt11Payment {
 	[Throws=NodeError]
-	PaymentId send([ByRef]Bolt11Invoice invoice);
+	PaymentId send([ByRef]Bolt11Invoice invoice, SendingParameters? sending_parameters);
 	[Throws=NodeError]
-	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat);
+	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes([ByRef]Bolt11Invoice invoice);
 	[Throws=NodeError]
@@ -135,7 +136,7 @@ interface Bolt12Payment {
 
 interface SpontaneousPayment {
 	[Throws=NodeError]
-	PaymentId send(u64 amount_msat, PublicKey node_id);
+	PaymentId send(u64 amount_msat, PublicKey node_id, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes(u64 amount_msat, PublicKey node_id);
 };
@@ -319,6 +320,13 @@ dictionary PaymentDetails {
 	u64 latest_update_timestamp;
 };
 
+dictionary SendingParameters {
+ u64? max_total_routing_fee_msat;
+ u32? max_total_cltv_expiry_delta;
+ u8? max_path_count;
+ u8? max_channel_saturation_power_of_half;
+};
+
 [NonExhaustive]
 enum Network {
 	"Bitcoin",

src/config.rs

@@ -1,5 +1,7 @@
 use std::time::Duration;
 
+use crate::payment::SendingParameters;
+
 use lightning::ln::msgs::SocketAddress;
 use lightning::util::config::UserConfig;
 use lightning::util::logger::Level as LogLevel;
@@ -86,6 +88,7 @@ pub(crate) const WALLET_KEYS_SEED_LEN: usize = 64;
 /// | `probing_liquidity_limit_multiplier` | 3 |
 /// | `log_level` | Debug |
 /// | `anchor_channels_config` | Some(..) |
+/// | `sending_parameters_config` | None |
 ///
 /// See [`AnchorChannelsConfig`] for more information on its respective default values.
 ///
@@ -147,6 +150,12 @@ pub struct Config {
 	/// closure. We *will* however still try to get the Anchor spending transactions confirmed
 	/// on-chain with the funds available.
 	pub anchor_channels_config: Option<AnchorChannelsConfig>,
+
+	/// Configuration options for payment routing and pathfinding.
+	///
+	/// Setting the `SendingParameters` provides flexibility to customize how payments are routed,
+	/// including setting limits on routing fees, CLTV expiry, and channel utilization.
+	pub sending_parameters_config: Option<SendingParameters>,
 }
 
 impl Default for Config {
@@ -164,6 +173,7 @@ impl Default for Config {
  probing_liquidity_limit_multiplier: DEFAULT_PROBING_LIQUIDITY_LIMIT_MULTIPLIER,
  log_level: DEFAULT_LOG_LEVEL,
  anchor_channels_config: Some(AnchorChannelsConfig::default()),
+ sending_parameters_config: None,
  }
 	}
 }

src/lib.rs

@@ -56,7 +56,7 @@
 //! node.event_handled();
 //!
 //! let invoice = Bolt11Invoice::from_str("INVOICE_STR").unwrap();
-//! node.bolt11_payment().send(&invoice).unwrap();
+//! node.bolt11_payment().send(&invoice, None).unwrap();
 //!
 //! node.stop().unwrap();
 //! }

src/payment/bolt11.rs

@@ -11,6 +11,7 @@ use crate::payment::store::{
 	LSPFeeLimits, PaymentDetails, PaymentDetailsUpdate, PaymentDirection, PaymentKind,
 	PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::peer_store::{PeerInfo, PeerStore};
 use crate::types::{ChannelManager, KeysManager};
 
@@ -69,13 +70,20 @@ impl Bolt11Payment {
 	}
 
 	/// Send a payment given an invoice.
-	pub fn send(&self, invoice: &Bolt11Invoice) -> Result<PaymentId, Error> {
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, invoice: &Bolt11Invoice, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
  }
 
- let (payment_hash, recipient_onion, route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
+ let (payment_hash, recipient_onion, mut route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
  log_error!(self.logger, "Failed to send payment due to the given invoice being \"zero-amount\". Please use send_using_amount instead.");
  Error::InvalidInvoice
  })?;
@@ -90,6 +98,40 @@ impl Bolt11Payment {
  }
  }
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let payment_secret = Some(*invoice.payment_secret());
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
 
@@ -148,14 +190,20 @@ impl Bolt11Payment {
  }
 	}
 
-	/// Send a payment given an invoice and an amount in millisatoshi.
+	/// Send a payment given an invoice and an amount in millisatoshis.
 	///
 	/// This will fail if the amount given is less than the value required by the given invoice.
 	///
 	/// This can be used to pay a so-called "zero-amount" invoice, i.e., an invoice that leaves the
 	/// amount paid to be determined by the user.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
 	pub fn send_using_amount(
  &self, invoice: &Bolt11Invoice, amount_msat: u64,
+ sending_parameters: Option<SendingParameters>,
 	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
@@ -196,9 +244,43 @@ impl Bolt11Payment {
  .with_bolt11_features(features.clone())
  .map_err(|_| Error::InvalidInvoice)?;
  }
- let route_params =
+ let mut route_params =
  RouteParameters::from_payment_params_and_value(payment_params, amount_msat);
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
  let recipient_fields = RecipientOnionFields::secret_only(*payment_secret);
 

src/payment/mod.rs

@@ -13,3 +13,52 @@ pub use onchain::OnchainPayment;
 pub use spontaneous::SpontaneousPayment;
 pub use store::{LSPFeeLimits, PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus};
 pub use unified_qr::{QrPaymentResult, UnifiedQrPayment};
+
+/// Represents information used to route a payment.
+#[derive(Clone, Debug, PartialEq)]
+pub struct SendingParameters {
+	/// The maximum total fees, in millisatoshi, that may accrue during route finding.
+	///
+	/// This limit also applies to the total fees that may arise while retrying failed payment
+	/// paths.
+	///
+	/// Note that values below a few sats may result in some paths being spuriously ignored.
+	pub max_total_routing_fee_msat: Option<u64>,
+
+	/// The maximum total CLTV delta we accept for the route.
+	///
+	/// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
+	///
+	/// [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`]: lightning::routing::router::DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA
+	pub max_total_cltv_expiry_delta: Option<u32>,
+
+	/// The maximum number of paths that may be used by (MPP) payments.
+	///
+	/// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
+	///
+	/// [`DEFAULT_MAX_PATH_COUNT`]: lightning::routing::router::DEFAULT_MAX_PATH_COUNT
+	pub max_path_count: Option<u8>,
+
+	/// Selects the maximum share of a channel's total capacity which will be sent over a channel,
+	/// as a power of 1/2.
+	///
+	/// A higher value prefers to send the payment using more MPP parts whereas
+	/// a lower value prefers to send larger MPP parts, potentially saturating channels and
+	/// increasing failure probability for those paths.
+	///
+	/// Note that this restriction will be relaxed during pathfinding after paths which meet this
+	/// restriction have been found. While paths which meet this criteria will be searched for, it
+	/// is ultimately up to the scorer to select them over other paths.
+	///
+	/// Examples:
+	///
+	/// | Value | Max Proportion of Channel Capacity Used |
+	/// |-------|-----------------------------------------|
+	/// | 0 | Up to 100% of the channel’s capacity |
+	/// | 1 | Up to 50% of the channel’s capacity |
+	/// | 2 | Up to 25% of the channel’s capacity |
+	/// | 3 | Up to 12.5% of the channel’s capacity |
+	///
+	/// Default value: 2
+	pub max_channel_saturation_power_of_half: Option<u8>,
+}

src/payment/spontaneous.rs

@@ -6,6 +6,7 @@ use crate::logger::{log_error, log_info, FilesystemLogger, Logger};
 use crate::payment::store::{
 	PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::types::{ChannelManager, KeysManager};
 
 use lightning::ln::channelmanager::{PaymentId, RecipientOnionFields, Retry, RetryableSendFailure};
@@ -41,8 +42,15 @@ impl SpontaneousPayment {
  Self { runtime, channel_manager, keys_manager, payment_store, config, logger }
 	}
 
-	/// Send a spontaneous, aka. "keysend", payment
-	pub fn send(&self, amount_msat: u64, node_id: PublicKey) -> Result<PaymentId, Error> {
+	/// Send a spontaneous aka. "keysend", payment.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, amount_msat: u64, node_id: PublicKey, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
@@ -61,10 +69,45 @@ impl SpontaneousPayment {
  }
  }
 
- let route_params = RouteParameters::from_payment_params_and_value(
+ let mut route_params = RouteParameters::from_payment_params_and_value(
  PaymentParameters::from_node_id(node_id, self.config.default_cltv_expiry_delta),
  amount_msat,
  );
+
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let recipient_fields = RecipientOnionFields::spontaneous_empty();
 
  match self.channel_manager.send_spontaneous_payment_with_retry(

src/payment/unified_qr.rs

@@ -143,7 +143,7 @@ impl UnifiedQrPayment {
  }
 
  if let Some(invoice) = uri_network_checked.extras.bolt11_invoice {
- match self.bolt11_invoice.send(&invoice) {
+ match self.bolt11_invoice.send(&invoice, None) {
  Ok(payment_id) => return Ok(QrPaymentResult::Bolt11 { payment_id }),
  Err(e) => log_error!(self.logger, "Failed to send BOLT11 invoice: {:?}. This is part of a unified QR code payment. Falling back to the on-chain transaction.", e),
  }

src/uniffi_types.rs

@@ -5,7 +5,7 @@
 
 pub use crate::graph::{ChannelInfo, ChannelUpdateInfo, NodeAnnouncementInfo, NodeInfo};
 pub use crate::payment::store::{LSPFeeLimits, PaymentDirection, PaymentKind, PaymentStatus};
-pub use crate::payment::QrPaymentResult;
+pub use crate::payment::{QrPaymentResult, SendingParameters};
 
 pub use lightning::events::{ClosureReason, PaymentFailureReason};
 pub use lightning::ln::{ChannelId, PaymentHash, PaymentPreimage, PaymentSecret};

bindings/kotlin/ldk-node-jvm/lib/src/test/kotlin/org/lightningdevkit/ldknode/LibraryTest.kt

@@ -224,7 +224,7 @@ class LibraryTest {
 
  val invoice = node2.bolt11Payment().receive(2500000u, "asdf", 9217u)
 
- node1.bolt11Payment().send(invoice)
+ node1.bolt11Payment().send(invoice, null)
 
  val paymentSuccessfulEvent = node1.waitNextEvent()
  println("Got event: $paymentSuccessfulEvent")

bindings/ldk_node.udl

@@ -16,6 +16,7 @@ dictionary Config {
 	u64 probing_liquidity_limit_multiplier;
 	LogLevel log_level;
 	AnchorChannelsConfig? anchor_channels_config;
+	SendingParameters? sending_parameters_config;
 };
 
 dictionary AnchorChannelsConfig {
@@ -93,9 +94,9 @@ interface Node {
 
 interface Bolt11Payment {
 	[Throws=NodeError]
-	PaymentId send([ByRef]Bolt11Invoice invoice);
+	PaymentId send([ByRef]Bolt11Invoice invoice, SendingParameters? sending_parameters);
 	[Throws=NodeError]
-	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat);
+	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes([ByRef]Bolt11Invoice invoice);
 	[Throws=NodeError]
@@ -135,7 +136,7 @@ interface Bolt12Payment {
 
 interface SpontaneousPayment {
 	[Throws=NodeError]
-	PaymentId send(u64 amount_msat, PublicKey node_id);
+	PaymentId send(u64 amount_msat, PublicKey node_id, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes(u64 amount_msat, PublicKey node_id);
 };
@@ -319,6 +320,13 @@ dictionary PaymentDetails {
 	u64 latest_update_timestamp;
 };
 
+dictionary SendingParameters {
+ u64? max_total_routing_fee_msat;
+ u32? max_total_cltv_expiry_delta;
+ u8? max_path_count;
+ u8? max_channel_saturation_power_of_half;
+};
+
 [NonExhaustive]
 enum Network {
 	"Bitcoin",

src/config.rs

@@ -1,5 +1,7 @@
 use std::time::Duration;
 
+use crate::payment::SendingParameters;
+
 use lightning::ln::msgs::SocketAddress;
 use lightning::util::config::UserConfig;
 use lightning::util::logger::Level as LogLevel;
@@ -86,6 +88,7 @@ pub(crate) const WALLET_KEYS_SEED_LEN: usize = 64;
 /// | `probing_liquidity_limit_multiplier` | 3 |
 /// | `log_level` | Debug |
 /// | `anchor_channels_config` | Some(..) |
+/// | `sending_parameters_config` | None |
 ///
 /// See [`AnchorChannelsConfig`] for more information on its respective default values.
 ///
@@ -147,6 +150,12 @@ pub struct Config {
 	/// closure. We *will* however still try to get the Anchor spending transactions confirmed
 	/// on-chain with the funds available.
 	pub anchor_channels_config: Option<AnchorChannelsConfig>,
+
+	/// Configuration options for payment routing and pathfinding.
+	///
+	/// Setting the `SendingParameters` provides flexibility to customize how payments are routed,
+	/// including setting limits on routing fees, CLTV expiry, and channel utilization.
+	pub sending_parameters_config: Option<SendingParameters>,
 }
 
 impl Default for Config {
@@ -164,6 +173,7 @@ impl Default for Config {
  probing_liquidity_limit_multiplier: DEFAULT_PROBING_LIQUIDITY_LIMIT_MULTIPLIER,
  log_level: DEFAULT_LOG_LEVEL,
  anchor_channels_config: Some(AnchorChannelsConfig::default()),
+ sending_parameters_config: None,
  }
 	}
 }

src/lib.rs

@@ -56,7 +56,7 @@
 //! node.event_handled();
 //!
 //! let invoice = Bolt11Invoice::from_str("INVOICE_STR").unwrap();
-//! node.bolt11_payment().send(&invoice).unwrap();
+//! node.bolt11_payment().send(&invoice, None).unwrap();
 //!
 //! node.stop().unwrap();
 //! }

src/payment/bolt11.rs

@@ -11,6 +11,7 @@ use crate::payment::store::{
 	LSPFeeLimits, PaymentDetails, PaymentDetailsUpdate, PaymentDirection, PaymentKind,
 	PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::peer_store::{PeerInfo, PeerStore};
 use crate::types::{ChannelManager, KeysManager};
 
@@ -69,13 +70,20 @@ impl Bolt11Payment {
 	}
 
 	/// Send a payment given an invoice.
-	pub fn send(&self, invoice: &Bolt11Invoice) -> Result<PaymentId, Error> {
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, invoice: &Bolt11Invoice, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
  }
 
- let (payment_hash, recipient_onion, route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
+ let (payment_hash, recipient_onion, mut route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
  log_error!(self.logger, "Failed to send payment due to the given invoice being \"zero-amount\". Please use send_using_amount instead.");
  Error::InvalidInvoice
  })?;
@@ -90,6 +98,40 @@ impl Bolt11Payment {
  }
  }
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let payment_secret = Some(*invoice.payment_secret());
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
 
@@ -148,14 +190,20 @@ impl Bolt11Payment {
  }
 	}
 
-	/// Send a payment given an invoice and an amount in millisatoshi.
+	/// Send a payment given an invoice and an amount in millisatoshis.
 	///
 	/// This will fail if the amount given is less than the value required by the given invoice.
 	///
 	/// This can be used to pay a so-called "zero-amount" invoice, i.e., an invoice that leaves the
 	/// amount paid to be determined by the user.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
 	pub fn send_using_amount(
  &self, invoice: &Bolt11Invoice, amount_msat: u64,
+ sending_parameters: Option<SendingParameters>,
 	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
@@ -196,9 +244,43 @@ impl Bolt11Payment {
  .with_bolt11_features(features.clone())
  .map_err(|_| Error::InvalidInvoice)?;
  }
- let route_params =
+ let mut route_params =
  RouteParameters::from_payment_params_and_value(payment_params, amount_msat);
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
  let recipient_fields = RecipientOnionFields::secret_only(*payment_secret);
 

src/payment/mod.rs

@@ -13,3 +13,52 @@ pub use onchain::OnchainPayment;
 pub use spontaneous::SpontaneousPayment;
 pub use store::{LSPFeeLimits, PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus};
 pub use unified_qr::{QrPaymentResult, UnifiedQrPayment};
+
+/// Represents information used to route a payment.
+#[derive(Clone, Debug, PartialEq)]
+pub struct SendingParameters {
+	/// The maximum total fees, in millisatoshi, that may accrue during route finding.
+	///
+	/// This limit also applies to the total fees that may arise while retrying failed payment
+	/// paths.
+	///
+	/// Note that values below a few sats may result in some paths being spuriously ignored.
+	pub max_total_routing_fee_msat: Option<u64>,
+
+	/// The maximum total CLTV delta we accept for the route.
+	///
+	/// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
+	///
+	/// [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`]: lightning::routing::router::DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA
+	pub max_total_cltv_expiry_delta: Option<u32>,
+
+	/// The maximum number of paths that may be used by (MPP) payments.
+	///
+	/// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
+	///
+	/// [`DEFAULT_MAX_PATH_COUNT`]: lightning::routing::router::DEFAULT_MAX_PATH_COUNT
+	pub max_path_count: Option<u8>,
+
+	/// Selects the maximum share of a channel's total capacity which will be sent over a channel,
+	/// as a power of 1/2.
+	///
+	/// A higher value prefers to send the payment using more MPP parts whereas
+	/// a lower value prefers to send larger MPP parts, potentially saturating channels and
+	/// increasing failure probability for those paths.
+	///
+	/// Note that this restriction will be relaxed during pathfinding after paths which meet this
+	/// restriction have been found. While paths which meet this criteria will be searched for, it
+	/// is ultimately up to the scorer to select them over other paths.
+	///
+	/// Examples:
+	///
+	/// | Value | Max Proportion of Channel Capacity Used |
+	/// |-------|-----------------------------------------|
+	/// | 0 | Up to 100% of the channel’s capacity |
+	/// | 1 | Up to 50% of the channel’s capacity |
+	/// | 2 | Up to 25% of the channel’s capacity |
+	/// | 3 | Up to 12.5% of the channel’s capacity |
+	///
+	/// Default value: 2
+	pub max_channel_saturation_power_of_half: Option<u8>,
+}

src/payment/spontaneous.rs

@@ -6,6 +6,7 @@ use crate::logger::{log_error, log_info, FilesystemLogger, Logger};
 use crate::payment::store::{
 	PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::types::{ChannelManager, KeysManager};
 
 use lightning::ln::channelmanager::{PaymentId, RecipientOnionFields, Retry, RetryableSendFailure};
@@ -41,8 +42,15 @@ impl SpontaneousPayment {
  Self { runtime, channel_manager, keys_manager, payment_store, config, logger }
 	}
 
-	/// Send a spontaneous, aka. "keysend", payment
-	pub fn send(&self, amount_msat: u64, node_id: PublicKey) -> Result<PaymentId, Error> {
+	/// Send a spontaneous aka. "keysend", payment.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, amount_msat: u64, node_id: PublicKey, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
@@ -61,10 +69,45 @@ impl SpontaneousPayment {
  }
  }
 
- let route_params = RouteParameters::from_payment_params_and_value(
+ let mut route_params = RouteParameters::from_payment_params_and_value(
  PaymentParameters::from_node_id(node_id, self.config.default_cltv_expiry_delta),
  amount_msat,
  );
+
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let recipient_fields = RecipientOnionFields::spontaneous_empty();
 
  match self.channel_manager.send_spontaneous_payment_with_retry(

src/payment/unified_qr.rs

@@ -143,7 +143,7 @@ impl UnifiedQrPayment {
  }
 
  if let Some(invoice) = uri_network_checked.extras.bolt11_invoice {
- match self.bolt11_invoice.send(&invoice) {
+ match self.bolt11_invoice.send(&invoice, None) {
  Ok(payment_id) => return Ok(QrPaymentResult::Bolt11 { payment_id }),
  Err(e) => log_error!(self.logger, "Failed to send BOLT11 invoice: {:?}. This is part of a unified QR code payment. Falling back to the on-chain transaction.", e),
  }

src/uniffi_types.rs

@@ -5,7 +5,7 @@
 
 pub use crate::graph::{ChannelInfo, ChannelUpdateInfo, NodeAnnouncementInfo, NodeInfo};
 pub use crate::payment::store::{LSPFeeLimits, PaymentDirection, PaymentKind, PaymentStatus};
-pub use crate::payment::QrPaymentResult;
+pub use crate::payment::{QrPaymentResult, SendingParameters};
 
 pub use lightning::events::{ClosureReason, PaymentFailureReason};
 pub use lightning::ln::{ChannelId, PaymentHash, PaymentPreimage, PaymentSecret};

bindings/kotlin/ldk-node-jvm/lib/src/test/kotlin/org/lightningdevkit/ldknode/LibraryTest.kt

@@ -224,7 +224,7 @@ class LibraryTest {
 
  val invoice = node2.bolt11Payment().receive(2500000u, "asdf", 9217u)
 
- node1.bolt11Payment().send(invoice)
+ node1.bolt11Payment().send(invoice, null)
 
  val paymentSuccessfulEvent = node1.waitNextEvent()
  println("Got event: $paymentSuccessfulEvent")

bindings/ldk_node.udl

@@ -16,6 +16,7 @@ dictionary Config {
 	u64 probing_liquidity_limit_multiplier;
 	LogLevel log_level;
 	AnchorChannelsConfig? anchor_channels_config;
+	SendingParameters? sending_parameters_config;
 };
 
 dictionary AnchorChannelsConfig {
@@ -93,9 +94,9 @@ interface Node {
 
 interface Bolt11Payment {
 	[Throws=NodeError]
-	PaymentId send([ByRef]Bolt11Invoice invoice);
+	PaymentId send([ByRef]Bolt11Invoice invoice, SendingParameters? sending_parameters);
 	[Throws=NodeError]
-	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat);
+	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes([ByRef]Bolt11Invoice invoice);
 	[Throws=NodeError]
@@ -135,7 +136,7 @@ interface Bolt12Payment {
 
 interface SpontaneousPayment {
 	[Throws=NodeError]
-	PaymentId send(u64 amount_msat, PublicKey node_id);
+	PaymentId send(u64 amount_msat, PublicKey node_id, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes(u64 amount_msat, PublicKey node_id);
 };
@@ -319,6 +320,13 @@ dictionary PaymentDetails {
 	u64 latest_update_timestamp;
 };
 
+dictionary SendingParameters {
+ u64? max_total_routing_fee_msat;
+ u32? max_total_cltv_expiry_delta;
+ u8? max_path_count;
+ u8? max_channel_saturation_power_of_half;
+};
+
 [NonExhaustive]
 enum Network {
 	"Bitcoin",

src/config.rs

@@ -1,5 +1,7 @@
 use std::time::Duration;
 
+use crate::payment::SendingParameters;
+
 use lightning::ln::msgs::SocketAddress;
 use lightning::util::config::UserConfig;
 use lightning::util::logger::Level as LogLevel;
@@ -86,6 +88,7 @@ pub(crate) const WALLET_KEYS_SEED_LEN: usize = 64;
 /// | `probing_liquidity_limit_multiplier` | 3 |
 /// | `log_level` | Debug |
 /// | `anchor_channels_config` | Some(..) |
+/// | `sending_parameters_config` | None |
 ///
 /// See [`AnchorChannelsConfig`] for more information on its respective default values.
 ///
@@ -147,6 +150,12 @@ pub struct Config {
 	/// closure. We *will* however still try to get the Anchor spending transactions confirmed
 	/// on-chain with the funds available.
 	pub anchor_channels_config: Option<AnchorChannelsConfig>,
+
+	/// Configuration options for payment routing and pathfinding.
+	///
+	/// Setting the `SendingParameters` provides flexibility to customize how payments are routed,
+	/// including setting limits on routing fees, CLTV expiry, and channel utilization.
+	pub sending_parameters_config: Option<SendingParameters>,
 }
 
 impl Default for Config {
@@ -164,6 +173,7 @@ impl Default for Config {
  probing_liquidity_limit_multiplier: DEFAULT_PROBING_LIQUIDITY_LIMIT_MULTIPLIER,
  log_level: DEFAULT_LOG_LEVEL,
  anchor_channels_config: Some(AnchorChannelsConfig::default()),
+ sending_parameters_config: None,
  }
 	}
 }

src/lib.rs

@@ -56,7 +56,7 @@
 //! node.event_handled();
 //!
 //! let invoice = Bolt11Invoice::from_str("INVOICE_STR").unwrap();
-//! node.bolt11_payment().send(&invoice).unwrap();
+//! node.bolt11_payment().send(&invoice, None).unwrap();
 //!
 //! node.stop().unwrap();
 //! }

src/payment/bolt11.rs

@@ -11,6 +11,7 @@ use crate::payment::store::{
 	LSPFeeLimits, PaymentDetails, PaymentDetailsUpdate, PaymentDirection, PaymentKind,
 	PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::peer_store::{PeerInfo, PeerStore};
 use crate::types::{ChannelManager, KeysManager};
 
@@ -69,13 +70,20 @@ impl Bolt11Payment {
 	}
 
 	/// Send a payment given an invoice.
-	pub fn send(&self, invoice: &Bolt11Invoice) -> Result<PaymentId, Error> {
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, invoice: &Bolt11Invoice, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
  }
 
- let (payment_hash, recipient_onion, route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
+ let (payment_hash, recipient_onion, mut route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
  log_error!(self.logger, "Failed to send payment due to the given invoice being \"zero-amount\". Please use send_using_amount instead.");
  Error::InvalidInvoice
  })?;
@@ -90,6 +98,40 @@ impl Bolt11Payment {
  }
  }
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let payment_secret = Some(*invoice.payment_secret());
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
 
@@ -148,14 +190,20 @@ impl Bolt11Payment {
  }
 	}
 
-	/// Send a payment given an invoice and an amount in millisatoshi.
+	/// Send a payment given an invoice and an amount in millisatoshis.
 	///
 	/// This will fail if the amount given is less than the value required by the given invoice.
 	///
 	/// This can be used to pay a so-called "zero-amount" invoice, i.e., an invoice that leaves the
 	/// amount paid to be determined by the user.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
 	pub fn send_using_amount(
  &self, invoice: &Bolt11Invoice, amount_msat: u64,
+ sending_parameters: Option<SendingParameters>,
 	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
@@ -196,9 +244,43 @@ impl Bolt11Payment {
  .with_bolt11_features(features.clone())
  .map_err(|_| Error::InvalidInvoice)?;
  }
- let route_params =
+ let mut route_params =
  RouteParameters::from_payment_params_and_value(payment_params, amount_msat);
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
  let recipient_fields = RecipientOnionFields::secret_only(*payment_secret);
 

src/payment/mod.rs

@@ -13,3 +13,52 @@ pub use onchain::OnchainPayment;
 pub use spontaneous::SpontaneousPayment;
 pub use store::{LSPFeeLimits, PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus};
 pub use unified_qr::{QrPaymentResult, UnifiedQrPayment};
+
+/// Represents information used to route a payment.
+#[derive(Clone, Debug, PartialEq)]
+pub struct SendingParameters {
+	/// The maximum total fees, in millisatoshi, that may accrue during route finding.
+	///
+	/// This limit also applies to the total fees that may arise while retrying failed payment
+	/// paths.
+	///
+	/// Note that values below a few sats may result in some paths being spuriously ignored.
+	pub max_total_routing_fee_msat: Option<u64>,
+
+	/// The maximum total CLTV delta we accept for the route.
+	///
+	/// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
+	///
+	/// [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`]: lightning::routing::router::DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA
+	pub max_total_cltv_expiry_delta: Option<u32>,
+
+	/// The maximum number of paths that may be used by (MPP) payments.
+	///
+	/// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
+	///
+	/// [`DEFAULT_MAX_PATH_COUNT`]: lightning::routing::router::DEFAULT_MAX_PATH_COUNT
+	pub max_path_count: Option<u8>,
+
+	/// Selects the maximum share of a channel's total capacity which will be sent over a channel,
+	/// as a power of 1/2.
+	///
+	/// A higher value prefers to send the payment using more MPP parts whereas
+	/// a lower value prefers to send larger MPP parts, potentially saturating channels and
+	/// increasing failure probability for those paths.
+	///
+	/// Note that this restriction will be relaxed during pathfinding after paths which meet this
+	/// restriction have been found. While paths which meet this criteria will be searched for, it
+	/// is ultimately up to the scorer to select them over other paths.
+	///
+	/// Examples:
+	///
+	/// | Value | Max Proportion of Channel Capacity Used |
+	/// |-------|-----------------------------------------|
+	/// | 0 | Up to 100% of the channel’s capacity |
+	/// | 1 | Up to 50% of the channel’s capacity |
+	/// | 2 | Up to 25% of the channel’s capacity |
+	/// | 3 | Up to 12.5% of the channel’s capacity |
+	///
+	/// Default value: 2
+	pub max_channel_saturation_power_of_half: Option<u8>,
+}

src/payment/spontaneous.rs

@@ -6,6 +6,7 @@ use crate::logger::{log_error, log_info, FilesystemLogger, Logger};
 use crate::payment::store::{
 	PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::types::{ChannelManager, KeysManager};
 
 use lightning::ln::channelmanager::{PaymentId, RecipientOnionFields, Retry, RetryableSendFailure};
@@ -41,8 +42,15 @@ impl SpontaneousPayment {
  Self { runtime, channel_manager, keys_manager, payment_store, config, logger }
 	}
 
-	/// Send a spontaneous, aka. "keysend", payment
-	pub fn send(&self, amount_msat: u64, node_id: PublicKey) -> Result<PaymentId, Error> {
+	/// Send a spontaneous aka. "keysend", payment.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, amount_msat: u64, node_id: PublicKey, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
@@ -61,10 +69,45 @@ impl SpontaneousPayment {
  }
  }
 
- let route_params = RouteParameters::from_payment_params_and_value(
+ let mut route_params = RouteParameters::from_payment_params_and_value(
  PaymentParameters::from_node_id(node_id, self.config.default_cltv_expiry_delta),
  amount_msat,
  );
+
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let recipient_fields = RecipientOnionFields::spontaneous_empty();
 
  match self.channel_manager.send_spontaneous_payment_with_retry(

src/payment/unified_qr.rs

@@ -143,7 +143,7 @@ impl UnifiedQrPayment {
  }
 
  if let Some(invoice) = uri_network_checked.extras.bolt11_invoice {
- match self.bolt11_invoice.send(&invoice) {
+ match self.bolt11_invoice.send(&invoice, None) {
  Ok(payment_id) => return Ok(QrPaymentResult::Bolt11 { payment_id }),
  Err(e) => log_error!(self.logger, "Failed to send BOLT11 invoice: {:?}. This is part of a unified QR code payment. Falling back to the on-chain transaction.", e),
  }

src/uniffi_types.rs

@@ -5,7 +5,7 @@
 
 pub use crate::graph::{ChannelInfo, ChannelUpdateInfo, NodeAnnouncementInfo, NodeInfo};
 pub use crate::payment::store::{LSPFeeLimits, PaymentDirection, PaymentKind, PaymentStatus};
-pub use crate::payment::QrPaymentResult;
+pub use crate::payment::{QrPaymentResult, SendingParameters};
 
 pub use lightning::events::{ClosureReason, PaymentFailureReason};
 pub use lightning::ln::{ChannelId, PaymentHash, PaymentPreimage, PaymentSecret};

bindings/kotlin/ldk-node-jvm/lib/src/test/kotlin/org/lightningdevkit/ldknode/LibraryTest.kt

@@ -224,7 +224,7 @@ class LibraryTest {
 
  val invoice = node2.bolt11Payment().receive(2500000u, "asdf", 9217u)
 
- node1.bolt11Payment().send(invoice)
+ node1.bolt11Payment().send(invoice, null)
 
  val paymentSuccessfulEvent = node1.waitNextEvent()
  println("Got event: $paymentSuccessfulEvent")

bindings/ldk_node.udl

@@ -16,6 +16,7 @@ dictionary Config {
 	u64 probing_liquidity_limit_multiplier;
 	LogLevel log_level;
 	AnchorChannelsConfig? anchor_channels_config;
+	SendingParameters? sending_parameters_config;
 };
 
 dictionary AnchorChannelsConfig {
@@ -93,9 +94,9 @@ interface Node {
 
 interface Bolt11Payment {
 	[Throws=NodeError]
-	PaymentId send([ByRef]Bolt11Invoice invoice);
+	PaymentId send([ByRef]Bolt11Invoice invoice, SendingParameters? sending_parameters);
 	[Throws=NodeError]
-	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat);
+	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes([ByRef]Bolt11Invoice invoice);
 	[Throws=NodeError]
@@ -135,7 +136,7 @@ interface Bolt12Payment {
 
 interface SpontaneousPayment {
 	[Throws=NodeError]
-	PaymentId send(u64 amount_msat, PublicKey node_id);
+	PaymentId send(u64 amount_msat, PublicKey node_id, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes(u64 amount_msat, PublicKey node_id);
 };
@@ -319,6 +320,13 @@ dictionary PaymentDetails {
 	u64 latest_update_timestamp;
 };
 
+dictionary SendingParameters {
+ u64? max_total_routing_fee_msat;
+ u32? max_total_cltv_expiry_delta;
+ u8? max_path_count;
+ u8? max_channel_saturation_power_of_half;
+};
+
 [NonExhaustive]
 enum Network {
 	"Bitcoin",

src/config.rs

@@ -1,5 +1,7 @@
 use std::time::Duration;
 
+use crate::payment::SendingParameters;
+
 use lightning::ln::msgs::SocketAddress;
 use lightning::util::config::UserConfig;
 use lightning::util::logger::Level as LogLevel;
@@ -86,6 +88,7 @@ pub(crate) const WALLET_KEYS_SEED_LEN: usize = 64;
 /// | `probing_liquidity_limit_multiplier` | 3 |
 /// | `log_level` | Debug |
 /// | `anchor_channels_config` | Some(..) |
+/// | `sending_parameters_config` | None |
 ///
 /// See [`AnchorChannelsConfig`] for more information on its respective default values.
 ///
@@ -147,6 +150,12 @@ pub struct Config {
 	/// closure. We *will* however still try to get the Anchor spending transactions confirmed
 	/// on-chain with the funds available.
 	pub anchor_channels_config: Option<AnchorChannelsConfig>,
+
+	/// Configuration options for payment routing and pathfinding.
+	///
+	/// Setting the `SendingParameters` provides flexibility to customize how payments are routed,
+	/// including setting limits on routing fees, CLTV expiry, and channel utilization.
+	pub sending_parameters_config: Option<SendingParameters>,
 }
 
 impl Default for Config {
@@ -164,6 +173,7 @@ impl Default for Config {
  probing_liquidity_limit_multiplier: DEFAULT_PROBING_LIQUIDITY_LIMIT_MULTIPLIER,
  log_level: DEFAULT_LOG_LEVEL,
  anchor_channels_config: Some(AnchorChannelsConfig::default()),
+ sending_parameters_config: None,
  }
 	}
 }

src/lib.rs

@@ -56,7 +56,7 @@
 //! node.event_handled();
 //!
 //! let invoice = Bolt11Invoice::from_str("INVOICE_STR").unwrap();
-//! node.bolt11_payment().send(&invoice).unwrap();
+//! node.bolt11_payment().send(&invoice, None).unwrap();
 //!
 //! node.stop().unwrap();
 //! }

src/payment/bolt11.rs

@@ -11,6 +11,7 @@ use crate::payment::store::{
 	LSPFeeLimits, PaymentDetails, PaymentDetailsUpdate, PaymentDirection, PaymentKind,
 	PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::peer_store::{PeerInfo, PeerStore};
 use crate::types::{ChannelManager, KeysManager};
 
@@ -69,13 +70,20 @@ impl Bolt11Payment {
 	}
 
 	/// Send a payment given an invoice.
-	pub fn send(&self, invoice: &Bolt11Invoice) -> Result<PaymentId, Error> {
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, invoice: &Bolt11Invoice, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
  }
 
- let (payment_hash, recipient_onion, route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
+ let (payment_hash, recipient_onion, mut route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
  log_error!(self.logger, "Failed to send payment due to the given invoice being \"zero-amount\". Please use send_using_amount instead.");
  Error::InvalidInvoice
  })?;
@@ -90,6 +98,40 @@ impl Bolt11Payment {
  }
  }
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let payment_secret = Some(*invoice.payment_secret());
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
 
@@ -148,14 +190,20 @@ impl Bolt11Payment {
  }
 	}
 
-	/// Send a payment given an invoice and an amount in millisatoshi.
+	/// Send a payment given an invoice and an amount in millisatoshis.
 	///
 	/// This will fail if the amount given is less than the value required by the given invoice.
 	///
 	/// This can be used to pay a so-called "zero-amount" invoice, i.e., an invoice that leaves the
 	/// amount paid to be determined by the user.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
 	pub fn send_using_amount(
  &self, invoice: &Bolt11Invoice, amount_msat: u64,
+ sending_parameters: Option<SendingParameters>,
 	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
@@ -196,9 +244,43 @@ impl Bolt11Payment {
  .with_bolt11_features(features.clone())
  .map_err(|_| Error::InvalidInvoice)?;
  }
- let route_params =
+ let mut route_params =
  RouteParameters::from_payment_params_and_value(payment_params, amount_msat);
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
  let recipient_fields = RecipientOnionFields::secret_only(*payment_secret);
 

src/payment/mod.rs

@@ -13,3 +13,52 @@ pub use onchain::OnchainPayment;
 pub use spontaneous::SpontaneousPayment;
 pub use store::{LSPFeeLimits, PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus};
 pub use unified_qr::{QrPaymentResult, UnifiedQrPayment};
+
+/// Represents information used to route a payment.
+#[derive(Clone, Debug, PartialEq)]
+pub struct SendingParameters {
+	/// The maximum total fees, in millisatoshi, that may accrue during route finding.
+	///
+	/// This limit also applies to the total fees that may arise while retrying failed payment
+	/// paths.
+	///
+	/// Note that values below a few sats may result in some paths being spuriously ignored.
+	pub max_total_routing_fee_msat: Option<u64>,
+
+	/// The maximum total CLTV delta we accept for the route.
+	///
+	/// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
+	///
+	/// [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`]: lightning::routing::router::DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA
+	pub max_total_cltv_expiry_delta: Option<u32>,
+
+	/// The maximum number of paths that may be used by (MPP) payments.
+	///
+	/// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
+	///
+	/// [`DEFAULT_MAX_PATH_COUNT`]: lightning::routing::router::DEFAULT_MAX_PATH_COUNT
+	pub max_path_count: Option<u8>,
+
+	/// Selects the maximum share of a channel's total capacity which will be sent over a channel,
+	/// as a power of 1/2.
+	///
+	/// A higher value prefers to send the payment using more MPP parts whereas
+	/// a lower value prefers to send larger MPP parts, potentially saturating channels and
+	/// increasing failure probability for those paths.
+	///
+	/// Note that this restriction will be relaxed during pathfinding after paths which meet this
+	/// restriction have been found. While paths which meet this criteria will be searched for, it
+	/// is ultimately up to the scorer to select them over other paths.
+	///
+	/// Examples:
+	///
+	/// | Value | Max Proportion of Channel Capacity Used |
+	/// |-------|-----------------------------------------|
+	/// | 0 | Up to 100% of the channel’s capacity |
+	/// | 1 | Up to 50% of the channel’s capacity |
+	/// | 2 | Up to 25% of the channel’s capacity |
+	/// | 3 | Up to 12.5% of the channel’s capacity |
+	///
+	/// Default value: 2
+	pub max_channel_saturation_power_of_half: Option<u8>,
+}

src/payment/spontaneous.rs

@@ -6,6 +6,7 @@ use crate::logger::{log_error, log_info, FilesystemLogger, Logger};
 use crate::payment::store::{
 	PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::types::{ChannelManager, KeysManager};
 
 use lightning::ln::channelmanager::{PaymentId, RecipientOnionFields, Retry, RetryableSendFailure};
@@ -41,8 +42,15 @@ impl SpontaneousPayment {
  Self { runtime, channel_manager, keys_manager, payment_store, config, logger }
 	}
 
-	/// Send a spontaneous, aka. "keysend", payment
-	pub fn send(&self, amount_msat: u64, node_id: PublicKey) -> Result<PaymentId, Error> {
+	/// Send a spontaneous aka. "keysend", payment.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, amount_msat: u64, node_id: PublicKey, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
@@ -61,10 +69,45 @@ impl SpontaneousPayment {
  }
  }
 
- let route_params = RouteParameters::from_payment_params_and_value(
+ let mut route_params = RouteParameters::from_payment_params_and_value(
  PaymentParameters::from_node_id(node_id, self.config.default_cltv_expiry_delta),
  amount_msat,
  );
+
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let recipient_fields = RecipientOnionFields::spontaneous_empty();
 
  match self.channel_manager.send_spontaneous_payment_with_retry(

src/payment/unified_qr.rs

@@ -143,7 +143,7 @@ impl UnifiedQrPayment {
  }
 
  if let Some(invoice) = uri_network_checked.extras.bolt11_invoice {
- match self.bolt11_invoice.send(&invoice) {
+ match self.bolt11_invoice.send(&invoice, None) {
  Ok(payment_id) => return Ok(QrPaymentResult::Bolt11 { payment_id }),
  Err(e) => log_error!(self.logger, "Failed to send BOLT11 invoice: {:?}. This is part of a unified QR code payment. Falling back to the on-chain transaction.", e),
  }

src/uniffi_types.rs

@@ -5,7 +5,7 @@
 
 pub use crate::graph::{ChannelInfo, ChannelUpdateInfo, NodeAnnouncementInfo, NodeInfo};
 pub use crate::payment::store::{LSPFeeLimits, PaymentDirection, PaymentKind, PaymentStatus};
-pub use crate::payment::QrPaymentResult;
+pub use crate::payment::{QrPaymentResult, SendingParameters};
 
 pub use lightning::events::{ClosureReason, PaymentFailureReason};
 pub use lightning::ln::{ChannelId, PaymentHash, PaymentPreimage, PaymentSecret};

bindings/kotlin/ldk-node-jvm/lib/src/test/kotlin/org/lightningdevkit/ldknode/LibraryTest.kt

@@ -224,7 +224,7 @@ class LibraryTest {
 
  val invoice = node2.bolt11Payment().receive(2500000u, "asdf", 9217u)
 
- node1.bolt11Payment().send(invoice)
+ node1.bolt11Payment().send(invoice, null)
 
  val paymentSuccessfulEvent = node1.waitNextEvent()
  println("Got event: $paymentSuccessfulEvent")

bindings/ldk_node.udl

@@ -16,6 +16,7 @@ dictionary Config {
 	u64 probing_liquidity_limit_multiplier;
 	LogLevel log_level;
 	AnchorChannelsConfig? anchor_channels_config;
+	SendingParameters? sending_parameters_config;
 };
 
 dictionary AnchorChannelsConfig {
@@ -93,9 +94,9 @@ interface Node {
 
 interface Bolt11Payment {
 	[Throws=NodeError]
-	PaymentId send([ByRef]Bolt11Invoice invoice);
+	PaymentId send([ByRef]Bolt11Invoice invoice, SendingParameters? sending_parameters);
 	[Throws=NodeError]
-	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat);
+	PaymentId send_using_amount([ByRef]Bolt11Invoice invoice, u64 amount_msat, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes([ByRef]Bolt11Invoice invoice);
 	[Throws=NodeError]
@@ -135,7 +136,7 @@ interface Bolt12Payment {
 
 interface SpontaneousPayment {
 	[Throws=NodeError]
-	PaymentId send(u64 amount_msat, PublicKey node_id);
+	PaymentId send(u64 amount_msat, PublicKey node_id, SendingParameters? sending_parameters);
 	[Throws=NodeError]
 	void send_probes(u64 amount_msat, PublicKey node_id);
 };
@@ -319,6 +320,13 @@ dictionary PaymentDetails {
 	u64 latest_update_timestamp;
 };
 
+dictionary SendingParameters {
+ u64? max_total_routing_fee_msat;
+ u32? max_total_cltv_expiry_delta;
+ u8? max_path_count;
+ u8? max_channel_saturation_power_of_half;
+};
+
 [NonExhaustive]
 enum Network {
 	"Bitcoin",

src/config.rs

@@ -1,5 +1,7 @@
 use std::time::Duration;
 
+use crate::payment::SendingParameters;
+
 use lightning::ln::msgs::SocketAddress;
 use lightning::util::config::UserConfig;
 use lightning::util::logger::Level as LogLevel;
@@ -86,6 +88,7 @@ pub(crate) const WALLET_KEYS_SEED_LEN: usize = 64;
 /// | `probing_liquidity_limit_multiplier` | 3 |
 /// | `log_level` | Debug |
 /// | `anchor_channels_config` | Some(..) |
+/// | `sending_parameters_config` | None |
 ///
 /// See [`AnchorChannelsConfig`] for more information on its respective default values.
 ///
@@ -147,6 +150,12 @@ pub struct Config {
 	/// closure. We *will* however still try to get the Anchor spending transactions confirmed
 	/// on-chain with the funds available.
 	pub anchor_channels_config: Option<AnchorChannelsConfig>,
+
+	/// Configuration options for payment routing and pathfinding.
+	///
+	/// Setting the `SendingParameters` provides flexibility to customize how payments are routed,
+	/// including setting limits on routing fees, CLTV expiry, and channel utilization.
+	pub sending_parameters_config: Option<SendingParameters>,
 }
 
 impl Default for Config {
@@ -164,6 +173,7 @@ impl Default for Config {
  probing_liquidity_limit_multiplier: DEFAULT_PROBING_LIQUIDITY_LIMIT_MULTIPLIER,
  log_level: DEFAULT_LOG_LEVEL,
  anchor_channels_config: Some(AnchorChannelsConfig::default()),
+ sending_parameters_config: None,
  }
 	}
 }

src/lib.rs

@@ -56,7 +56,7 @@
 //! node.event_handled();
 //!
 //! let invoice = Bolt11Invoice::from_str("INVOICE_STR").unwrap();
-//! node.bolt11_payment().send(&invoice).unwrap();
+//! node.bolt11_payment().send(&invoice, None).unwrap();
 //!
 //! node.stop().unwrap();
 //! }

src/payment/bolt11.rs

@@ -11,6 +11,7 @@ use crate::payment::store::{
 	LSPFeeLimits, PaymentDetails, PaymentDetailsUpdate, PaymentDirection, PaymentKind,
 	PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::peer_store::{PeerInfo, PeerStore};
 use crate::types::{ChannelManager, KeysManager};
 
@@ -69,13 +70,20 @@ impl Bolt11Payment {
 	}
 
 	/// Send a payment given an invoice.
-	pub fn send(&self, invoice: &Bolt11Invoice) -> Result<PaymentId, Error> {
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, invoice: &Bolt11Invoice, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
  }
 
- let (payment_hash, recipient_onion, route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
+ let (payment_hash, recipient_onion, mut route_params) = payment::payment_parameters_from_invoice(&invoice).map_err(|_| {
  log_error!(self.logger, "Failed to send payment due to the given invoice being \"zero-amount\". Please use send_using_amount instead.");
  Error::InvalidInvoice
  })?;
@@ -90,6 +98,40 @@ impl Bolt11Payment {
  }
  }
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let payment_secret = Some(*invoice.payment_secret());
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
 
@@ -148,14 +190,20 @@ impl Bolt11Payment {
  }
 	}
 
-	/// Send a payment given an invoice and an amount in millisatoshi.
+	/// Send a payment given an invoice and an amount in millisatoshis.
 	///
 	/// This will fail if the amount given is less than the value required by the given invoice.
 	///
 	/// This can be used to pay a so-called "zero-amount" invoice, i.e., an invoice that leaves the
 	/// amount paid to be determined by the user.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
 	pub fn send_using_amount(
  &self, invoice: &Bolt11Invoice, amount_msat: u64,
+ sending_parameters: Option<SendingParameters>,
 	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
@@ -196,9 +244,43 @@ impl Bolt11Payment {
  .with_bolt11_features(features.clone())
  .map_err(|_| Error::InvalidInvoice)?;
  }
- let route_params =
+ let mut route_params =
  RouteParameters::from_payment_params_and_value(payment_params, amount_msat);
 
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let retry_strategy = Retry::Timeout(LDK_PAYMENT_RETRY_TIMEOUT);
  let recipient_fields = RecipientOnionFields::secret_only(*payment_secret);
 

src/payment/mod.rs

@@ -13,3 +13,52 @@ pub use onchain::OnchainPayment;
 pub use spontaneous::SpontaneousPayment;
 pub use store::{LSPFeeLimits, PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus};
 pub use unified_qr::{QrPaymentResult, UnifiedQrPayment};
+
+/// Represents information used to route a payment.
+#[derive(Clone, Debug, PartialEq)]
+pub struct SendingParameters {
+	/// The maximum total fees, in millisatoshi, that may accrue during route finding.
+	///
+	/// This limit also applies to the total fees that may arise while retrying failed payment
+	/// paths.
+	///
+	/// Note that values below a few sats may result in some paths being spuriously ignored.
+	pub max_total_routing_fee_msat: Option<u64>,
+
+	/// The maximum total CLTV delta we accept for the route.
+	///
+	/// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
+	///
+	/// [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`]: lightning::routing::router::DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA
+	pub max_total_cltv_expiry_delta: Option<u32>,
+
+	/// The maximum number of paths that may be used by (MPP) payments.
+	///
+	/// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
+	///
+	/// [`DEFAULT_MAX_PATH_COUNT`]: lightning::routing::router::DEFAULT_MAX_PATH_COUNT
+	pub max_path_count: Option<u8>,
+
+	/// Selects the maximum share of a channel's total capacity which will be sent over a channel,
+	/// as a power of 1/2.
+	///
+	/// A higher value prefers to send the payment using more MPP parts whereas
+	/// a lower value prefers to send larger MPP parts, potentially saturating channels and
+	/// increasing failure probability for those paths.
+	///
+	/// Note that this restriction will be relaxed during pathfinding after paths which meet this
+	/// restriction have been found. While paths which meet this criteria will be searched for, it
+	/// is ultimately up to the scorer to select them over other paths.
+	///
+	/// Examples:
+	///
+	/// | Value | Max Proportion of Channel Capacity Used |
+	/// |-------|-----------------------------------------|
+	/// | 0 | Up to 100% of the channel’s capacity |
+	/// | 1 | Up to 50% of the channel’s capacity |
+	/// | 2 | Up to 25% of the channel’s capacity |
+	/// | 3 | Up to 12.5% of the channel’s capacity |
+	///
+	/// Default value: 2
+	pub max_channel_saturation_power_of_half: Option<u8>,
+}

src/payment/spontaneous.rs

@@ -6,6 +6,7 @@ use crate::logger::{log_error, log_info, FilesystemLogger, Logger};
 use crate::payment::store::{
 	PaymentDetails, PaymentDirection, PaymentKind, PaymentStatus, PaymentStore,
 };
+use crate::payment::SendingParameters;
 use crate::types::{ChannelManager, KeysManager};
 
 use lightning::ln::channelmanager::{PaymentId, RecipientOnionFields, Retry, RetryableSendFailure};
@@ -41,8 +42,15 @@ impl SpontaneousPayment {
  Self { runtime, channel_manager, keys_manager, payment_store, config, logger }
 	}
 
-	/// Send a spontaneous, aka. "keysend", payment
-	pub fn send(&self, amount_msat: u64, node_id: PublicKey) -> Result<PaymentId, Error> {
+	/// Send a spontaneous aka. "keysend", payment.
+	///
+	/// If [`SendingParameters`] are provided they will override the node's default routing parameters
+	/// on a per-field basis. Each field in `SendingParameters` that is set replaces the corresponding
+	/// default value. Fields that are not set fall back to the node's configured defaults. If no
+	/// `SendingParameters` are provided, the method fully relies on these defaults.
+	pub fn send(
+ &self, amount_msat: u64, node_id: PublicKey, sending_parameters: Option<SendingParameters>,
+	) -> Result<PaymentId, Error> {
  let rt_lock = self.runtime.read().unwrap();
  if rt_lock.is_none() {
  return Err(Error::NotRunning);
@@ -61,10 +69,45 @@ impl SpontaneousPayment {
  }
  }
 
- let route_params = RouteParameters::from_payment_params_and_value(
+ let mut route_params = RouteParameters::from_payment_params_and_value(
  PaymentParameters::from_node_id(node_id, self.config.default_cltv_expiry_delta),
  amount_msat,
  );
+
+ if let Some(user_set_params) = sending_parameters {
+ if let Some(mut default_params) =
+ self.config.sending_parameters_config.as_ref().cloned()
+ {
+ default_params.max_total_routing_fee_msat = user_set_params
+ .max_total_routing_fee_msat
+ .or(default_params.max_total_routing_fee_msat);
+ default_params.max_total_cltv_expiry_delta = user_set_params
+ .max_total_cltv_expiry_delta
+ .or(default_params.max_total_cltv_expiry_delta);
+ default_params.max_path_count =
+ user_set_params.max_path_count.or(default_params.max_path_count);
+ default_params.max_channel_saturation_power_of_half = user_set_params
+ .max_channel_saturation_power_of_half
+ .or(default_params.max_channel_saturation_power_of_half);
+
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+ } else if let Some(default_params) = &self.config.sending_parameters_config {
+ route_params.max_total_routing_fee_msat = default_params.max_total_routing_fee_msat;
+ route_params.payment_params.max_total_cltv_expiry_delta =
+ default_params.max_total_cltv_expiry_delta.unwrap_or_default();
+ route_params.payment_params.max_path_count =
+ default_params.max_path_count.unwrap_or_default();
+ route_params.payment_params.max_channel_saturation_power_of_half =
+ default_params.max_channel_saturation_power_of_half.unwrap_or_default();
+ }
+
  let recipient_fields = RecipientOnionFields::spontaneous_empty();
 
  match self.channel_manager.send_spontaneous_payment_with_retry(

src/payment/unified_qr.rs

@@ -143,7 +143,7 @@ impl UnifiedQrPayment {
  }
 
  if let Some(invoice) = uri_network_checked.extras.bolt11_invoice {
- match self.bolt11_invoice.send(&invoice) {
+ match self.bolt11_invoice.send(&invoice, None) {
  Ok(payment_id) => return Ok(QrPaymentResult::Bolt11 { payment_id }),
  Err(e) => log_error!(self.logger, "Failed to send BOLT11 invoice: {:?}. This is part of a unified QR code payment. Falling back to the on-chain transaction.", e),
  }

src/uniffi_types.rs

@@ -5,7 +5,7 @@
 
 pub use crate::graph::{ChannelInfo, ChannelUpdateInfo, NodeAnnouncementInfo, NodeInfo};
 pub use crate::payment::store::{LSPFeeLimits, PaymentDirection, PaymentKind, PaymentStatus};
-pub use crate::payment::QrPaymentResult;
+pub use crate::payment::{QrPaymentResult, SendingParameters};
 
 pub use lightning::events::{ClosureReason, PaymentFailureReason};
 pub use lightning::ln::{ChannelId, PaymentHash, PaymentPreimage, PaymentSecret};