Yield call to send_payment after a timeout and return a pending payment

libs/sdk-bindings/src/breez_sdk.udl

@@ -401,6 +401,7 @@ interface BreezEvent {
     NewBlock(u32 block);
     InvoicePaid(InvoicePaidDetails details);
     Synced();
+    PaymentStarted(Payment details);
     PaymentSucceed(Payment details);
     PaymentFailed(PaymentFailedData details);
     BackupStarted();
@@ -749,6 +750,7 @@ dictionary SendPaymentRequest {
     string bolt11;
     u64? amount_msat = null;
     string? label = null;
+    u64? pending_timeout_sec = null;
 };
 
 dictionary SendSpontaneousPaymentRequest {

libs/sdk-core/src/breez_services.rs

@@ -94,6 +94,10 @@ pub enum BreezEvent {
     },
     /// Indicates that the local SDK state has just been sync-ed with the remote components
     Synced,
+    /// Indicates that an outgoing payment has started
+    PaymentStarted {
+        details: Payment,
+    },
     /// Indicates that an outgoing payment has been completed successfully
     PaymentSucceed {
         details: Payment,
@@ -116,6 +120,11 @@ pub enum BreezEvent {
         details: SwapInfo,
     },
 }
+impl BreezEvent {
+    pub(crate) fn payment_started(payment: Payment) -> Self {
+        Self::PaymentStarted { details: payment }
+    }
+}
 
 #[derive(Clone, Debug, PartialEq)]
 pub struct BackupFailedData {
@@ -282,7 +291,7 @@ impl BreezServices {
     /// Calling `send_payment` ensures that the payment is not already completed, if so it will result in an error.
     /// If the invoice doesn't specify an amount, the amount is taken from the `amount_msat` arg.
     pub async fn send_payment(
-        &self,
+        self: &Arc<BreezServices>,
         req: SendPaymentRequest,
     ) -> Result<SendPaymentResponse, SendPaymentError> {
         self.start_node().await?;
@@ -314,25 +323,38 @@ impl BreezServices {
         {
             Some(_) => Err(SendPaymentError::AlreadyPaid),
             None => {
-                self.persist_pending_payment(&parsed_invoice, amount_msat, req.label.clone())?;
-                let payment_res = self
-                    .node_api
-                    .send_payment(
-                        parsed_invoice.bolt11.clone(),
-                        req.amount_msat,
-                        req.label.clone(),
-                    )
-                    .map_err(Into::into)
-                    .await;
-                let payment = self
-                    .on_payment_completed(
-                        parsed_invoice.payee_pubkey.clone(),
-                        Some(parsed_invoice),
-                        req.label,
-                        payment_res,
-                    )
+                let pending_payment =
+                    self.persist_pending_payment(&parsed_invoice, amount_msat, req.label.clone())?;
+                self.notify_event_listeners(BreezEvent::payment_started(pending_payment.clone()))
                     .await?;
-                Ok(SendPaymentResponse { payment })
+
+                let (tx, rx) = tokio::sync::oneshot::channel();
+                let cloned = self.clone();
+                tokio::spawn(async move {
+                    let label = req.label;
+                    let payee_pk = parsed_invoice.payee_pubkey.clone();
+                    let bolt11 = parsed_invoice.bolt11.clone();
+
+                    let payment_res = cloned
+                        .node_api
+                        .send_payment(bolt11, req.amount_msat, label.clone())
+                        .map_err(Into::into)
+                        .await;
+                    let result = cloned
+                        .on_payment_completed(payee_pk, Some(parsed_invoice), label, payment_res)
+                        .await;
+                    let _ = tx.send(result);
+                });
+
+                let pending_timeout_sec = req.pending_timeout_sec.unwrap_or(u64::MAX);
+                match tokio::time::timeout(Duration::from_secs(pending_timeout_sec), rx).await {
+                    Ok(Ok(result)) => result.map(SendPaymentResponse::from_payment),
+                    Ok(Err(_)) => {
+                        error!("The send_payment sender (tx) dropped without sending a message");
+                        Err(SendPaymentError::payment_failed("Payment call interrupted"))
+                    }
+                    Err(_) => Ok(SendPaymentResponse::from_payment(pending_payment)),
+                }
             }
         }
     }
@@ -367,7 +389,10 @@ impl BreezServices {
     /// is made.
     ///
     /// This method will return an [anyhow::Error] when any validation check fails.
-    pub async fn lnurl_pay(&self, req: LnUrlPayRequest) -> Result<LnUrlPayResult, LnUrlPayError> {
+    pub async fn lnurl_pay(
+        self: &Arc<BreezServices>,
+        req: LnUrlPayRequest,
+    ) -> Result<LnUrlPayResult, LnUrlPayError> {
         match validate_lnurl_pay(
             req.amount_msat,
             req.comment,
@@ -382,8 +407,8 @@ impl BreezServices {
             ValidatedCallbackResponse::EndpointSuccess { data: cb } => {
                 let pay_req = SendPaymentRequest {
                     bolt11: cb.pr.clone(),
-                    amount_msat: None,
                     label: req.payment_label,
+                    ..Default::default()
                 };
                 let invoice = parse_invoice(cb.pr.as_str())?;
 
@@ -1171,7 +1196,7 @@ impl BreezServices {
         invoice: &LNInvoice,
         amount_msat: u64,
         label: Option<String>,
-    ) -> Result<(), SendPaymentError> {
+    ) -> Result<Payment, SendPaymentError> {
         self.persister.insert_or_update_payments(
             &[Payment {
                 id: invoice.payment_hash.clone(),
@@ -1218,7 +1243,12 @@ impl BreezServices {
                 attempted_error: None,
             },
         )?;
-        Ok(())
+
+        self.persister
+            .get_payment_by_hash(&invoice.payment_hash)?
+            .ok_or(SendPaymentError::Generic {
+                err: "Payment not found".to_string(),
+            })
     }
 
     async fn on_payment_completed(

libs/sdk-core/src/bridge_generated.io.rs

@@ -1072,6 +1072,7 @@ impl Wire2Api<SendPaymentRequest> for wire_SendPaymentRequest {
             bolt11: self.bolt11.wire2api(),
             amount_msat: self.amount_msat.wire2api(),
             label: self.label.wire2api(),
+            pending_timeout_sec: self.pending_timeout_sec.wire2api(),
         }
     }
 }
@@ -1390,6 +1391,7 @@ pub struct wire_SendPaymentRequest {
     bolt11: *mut wire_uint_8_list,
     amount_msat: *mut u64,
     label: *mut wire_uint_8_list,
+    pending_timeout_sec: *mut u64,
 }
 
 #[repr(C)]
@@ -1997,6 +1999,7 @@ impl NewWithNullPtr for wire_SendPaymentRequest {
             bolt11: core::ptr::null_mut(),
             amount_msat: core::ptr::null_mut(),
             label: core::ptr::null_mut(),
+            pending_timeout_sec: core::ptr::null_mut(),
         }
     }
 }

libs/sdk-core/src/bridge_generated.rs

@@ -1105,19 +1105,22 @@ impl support::IntoDart for BreezEvent {
                 vec![1.into_dart(), details.into_into_dart().into_dart()]
             }
             Self::Synced => vec![2.into_dart()],
-            Self::PaymentSucceed { details } => {
+            Self::PaymentStarted { details } => {
                 vec![3.into_dart(), details.into_into_dart().into_dart()]
             }
-            Self::PaymentFailed { details } => {
+            Self::PaymentSucceed { details } => {
                 vec![4.into_dart(), details.into_into_dart().into_dart()]
             }
-            Self::BackupStarted => vec![5.into_dart()],
-            Self::BackupSucceeded => vec![6.into_dart()],
+            Self::PaymentFailed { details } => {
+                vec![5.into_dart(), details.into_into_dart().into_dart()]
+            }
+            Self::BackupStarted => vec![6.into_dart()],
+            Self::BackupSucceeded => vec![7.into_dart()],
             Self::BackupFailed { details } => {
-                vec![7.into_dart(), details.into_into_dart().into_dart()]
+                vec![8.into_dart(), details.into_into_dart().into_dart()]
             }
             Self::SwapUpdated { details } => {
-                vec![8.into_dart(), details.into_into_dart().into_dart()]
+                vec![9.into_dart(), details.into_into_dart().into_dart()]
             }
         }
         .into_dart()

libs/sdk-core/src/error.rs

@@ -765,6 +765,13 @@ pub enum SendPaymentError {
     #[error("Service connectivity: {err}")]
     ServiceConnectivity { err: String },
 }
+impl SendPaymentError {
+    pub(crate) fn payment_failed(err: &str) -> Self {
+        Self::PaymentFailed {
+            err: err.to_string(),
+        }
+    }
+}
 
 impl From<anyhow::Error> for SendPaymentError {
     fn from(err: anyhow::Error) -> Self {

libs/sdk-core/src/models.rs

@@ -476,6 +476,7 @@ pub struct Config {
     /// the folder should exist before starting the SDK.
     pub working_dir: String,
     pub network: Network,
+    /// Maps to the CLN `retry_for` config when paying invoices (`lightning-pay`)
     pub payment_timeout_sec: u32,
     pub default_lsp_id: Option<String>,
     pub api_key: Option<String>,
@@ -871,14 +872,17 @@ pub struct ReceivePaymentResponse {
 }
 
 /// Represents a send payment request.
-#[derive(Clone, Debug, Serialize, Deserialize)]
+#[derive(Clone, Debug, Default, Serialize, Deserialize)]
 pub struct SendPaymentRequest {
     /// The bolt11 invoice
     pub bolt11: String,
     /// The amount to pay in millisatoshis. Should only be set when `bolt11` is a zero-amount invoice.
     pub amount_msat: Option<u64>,
     /// The external label or identifier of the [Payment]
     pub label: Option<String>,
+    /// If set, a timeout in seconds, that [crate::BreezServices::send_payment] will return a
+    /// pending payment if not already finished. Otherwise it will return when finished.
+    pub pending_timeout_sec: Option<u64>,
 }
 
 /// Represents a TLV entry for a keysend payment.
@@ -908,6 +912,11 @@ pub struct SendSpontaneousPaymentRequest {
 pub struct SendPaymentResponse {
     pub payment: Payment,
 }
+impl SendPaymentResponse {
+    pub(crate) fn from_payment(payment: Payment) -> Self {
+        Self { payment }
+    }
+}
 
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct ReportPaymentFailureDetails {

libs/sdk-flutter/ios/Classes/bridge_generated.h

@@ -112,6 +112,7 @@ typedef struct wire_SendPaymentRequest {
   struct wire_uint_8_list *bolt11;
   uint64_t *amount_msat;
   struct wire_uint_8_list *label;
+  uint64_t *pending_timeout_sec;
 } wire_SendPaymentRequest;
 
 typedef struct wire_TlvEntry {

libs/sdk-flutter/lib/bridge_generated.dart

@@ -396,6 +396,11 @@ sealed class BreezEvent with _$BreezEvent {
   /// Indicates that the local SDK state has just been sync-ed with the remote components
   const factory BreezEvent.synced() = BreezEvent_Synced;
 
+  /// Indicates that an outgoing payment has started
+  const factory BreezEvent.paymentStarted({
+    required Payment details,
+  }) = BreezEvent_PaymentStarted;
+
   /// Indicates that an outgoing payment has been completed successfully
   const factory BreezEvent.paymentSucceed({
     required Payment details,
@@ -520,6 +525,8 @@ class Config {
   /// the folder should exist before starting the SDK.
   final String workingDir;
   final Network network;
+
+  /// Maps to the CLN `retry_for` config when paying invoices (`lightning-pay`)
   final int paymentTimeoutSec;
   final String? defaultLspId;
   final String? apiKey;
@@ -1796,10 +1803,15 @@ class SendPaymentRequest {
   /// The external label or identifier of the [Payment]
   final String? label;
 
+  /// If set, a timeout in seconds, that [crate::BreezServices::send_payment] will return a
+  /// pending payment if not already finished. Otherwise it will return when finished.
+  final int? pendingTimeoutSec;
+
   const SendPaymentRequest({
     required this.bolt11,
     this.amountMsat,
     this.label,
+    this.pendingTimeoutSec,
   });
 }
 
@@ -3315,22 +3327,26 @@ class BreezSdkCoreImpl implements BreezSdkCore {
       case 2:
         return BreezEvent_Synced();
       case 3:
-        return BreezEvent_PaymentSucceed(
+        return BreezEvent_PaymentStarted(
           details: _wire2api_box_autoadd_payment(raw[1]),
         );
       case 4:
+        return BreezEvent_PaymentSucceed(
+          details: _wire2api_box_autoadd_payment(raw[1]),
+        );
+      case 5:
         return BreezEvent_PaymentFailed(
           details: _wire2api_box_autoadd_payment_failed_data(raw[1]),
         );
-      case 5:
-        return BreezEvent_BackupStarted();
       case 6:
-        return BreezEvent_BackupSucceeded();
+        return BreezEvent_BackupStarted();
       case 7:
+        return BreezEvent_BackupSucceeded();
+      case 8:
         return BreezEvent_BackupFailed(
           details: _wire2api_box_autoadd_backup_failed_data(raw[1]),
         );
-      case 8:
+      case 9:
         return BreezEvent_SwapUpdated(
           details: _wire2api_box_autoadd_swap_info(raw[1]),
         );
@@ -5044,6 +5060,7 @@ class BreezSdkCorePlatform extends FlutterRustBridgeBase<BreezSdkCoreWire> {
     wireObj.bolt11 = api2wire_String(apiObj.bolt11);
     wireObj.amount_msat = api2wire_opt_box_autoadd_u64(apiObj.amountMsat);
     wireObj.label = api2wire_opt_String(apiObj.label);
+    wireObj.pending_timeout_sec = api2wire_opt_box_autoadd_u64(apiObj.pendingTimeoutSec);
   }
 
   void _api_fill_to_wire_send_spontaneous_payment_request(
@@ -6590,6 +6607,8 @@ final class wire_SendPaymentRequest extends ffi.Struct {
   external ffi.Pointer<ffi.Uint64> amount_msat;
 
   external ffi.Pointer<wire_uint_8_list> label;
+
+  external ffi.Pointer<ffi.Uint64> pending_timeout_sec;
 }
 
 final class wire_TlvEntry extends ffi.Struct {