Add SendingParameters to bolt11 send_using_amount

Added the optional `SendingParameters` to `send_using_amount` in
`Bolt11Payment`. If the user provides sending params the values
will be overridden otherwise they'll use the default values.

Author: slanesuke

bindings/ldk_node.udl

@@ -96,7 +96,7 @@ interface Bolt11Payment {
 	[Throws=NodeError]
 	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]

src/payment/bolt11.rs

@@ -190,14 +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() {
@@ -238,9 +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);
 

tests/common/mod.rs

@@ -541,7 +541,7 @@ pub(crate) fn do_channel_full_cycle<E: ElectrumApi>(
 	let underpaid_amount = invoice_amount_2_msat - 1;
 	assert_eq!(
 		Err(NodeError::InvalidAmount),
-		node_a.bolt11_payment().send_using_amount(&invoice, underpaid_amount)
+		node_a.bolt11_payment().send_using_amount(&invoice, underpaid_amount, None)
 	);
 
 	println!("\nB overpaid receive");
@@ -550,7 +550,7 @@ pub(crate) fn do_channel_full_cycle<E: ElectrumApi>(
 
 	println!("\nA overpaid send");
 	let payment_id =
-		node_a.bolt11_payment().send_using_amount(&invoice, overpaid_amount_msat).unwrap();
+		node_a.bolt11_payment().send_using_amount(&invoice, overpaid_amount_msat, None).unwrap();
 	expect_event!(node_a, PaymentSuccessful);
 	let received_amount = match node_b.wait_next_event() {
 		ref e @ Event::PaymentReceived { amount_msat, .. } => {
@@ -584,7 +584,7 @@ pub(crate) fn do_channel_full_cycle<E: ElectrumApi>(
 	println!("\nA send_using_amount");
 	let payment_id = node_a
 		.bolt11_payment()
-		.send_using_amount(&variable_amount_invoice, determined_amount_msat)
+		.send_using_amount(&variable_amount_invoice, determined_amount_msat, None)
 		.unwrap();
 
 	expect_event!(node_a, PaymentSuccessful);