notifications: handle pending L402 payment

Author: bhandras

notifications/manager.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/lightninglabs/aperture/l402"
 	"github.com/lightninglabs/loop/swapserverrpc"
+	"github.com/lightningnetwork/lnd/lntypes"
 	"google.golang.org/grpc"
 )
 
@@ -169,7 +170,7 @@ func (m *Manager) Run(ctx context.Context) error {
 		// the FetchL402 method. As a client might not have outbound
 		// capacity yet, we'll retry until we get a valid response.
 		if !m.hasL402 {
-			_, err := m.cfg.CurrentToken()
+			token, err := m.cfg.CurrentToken()
 			if err != nil {
 				// We only log the error if it's not the case
 				// that we don't have a token yet to avoid
@@ -180,6 +181,15 @@ func (m *Manager) Run(ctx context.Context) error {
 				}
 				continue
 			}
+
+			// If the preimage is empty, we don't have a valid L402
+			// yet so we'll continue to retry with the incremental
+			// backoff.
+			emptyPreimage := lntypes.Preimage{}
+			if token.Preimage == emptyPreimage {
+				continue
+			}
+
 			m.hasL402 = true
 		}
 

notifications/manager_test.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/lightninglabs/aperture/l402"
 	"github.com/lightninglabs/loop/swapserverrpc"
+	"github.com/lightningnetwork/lnd/lntypes"
 	"github.com/stretchr/testify/require"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/metadata"
@@ -111,7 +112,9 @@ func TestManager_ReservationNotification(t *testing.T) {
 		Client: mockClient,
 		CurrentToken: func() (*l402.Token, error) {
 			// Simulate successful fetching of L402
-			return nil, nil
+			return &l402.Token{
+				Preimage: lntypes.Preimage{1, 2, 3},
+			}, nil
 		},
 	})
 
@@ -208,7 +211,10 @@ func TestManager_Backoff(t *testing.T) {
 	mgr := NewManager(&Config{
 		Client: mockClient,
 		CurrentToken: func() (*l402.Token, error) {
-			return &l402.Token{}, nil
+			// Simulate successful fetching of L402
+			return &l402.Token{
+				Preimage: lntypes.Preimage{1, 2, 3},
+			}, nil
 		},
 	})
 
@@ -297,7 +303,10 @@ func TestManager_MinAliveConnTime(t *testing.T) {
 		Client:           mockClient,
 		MinAliveConnTime: minAlive,
 		CurrentToken: func() (*l402.Token, error) {
-			return &l402.Token{}, nil
+			// Simulate successful fetching of L402
+			return &l402.Token{
+				Preimage: lntypes.Preimage{1, 2, 3},
+			}, nil
 		},
 	})