Merge pull request #123 from getAlby/feat/make-invoice-lnd

feat: lnd implementation of MakeInvoice

alby.go

@@ -93,6 +93,21 @@ func (svc *AlbyOAuthService) MakeInvoice(ctx context.Context, senderPubkey strin
 		}).Errorf("App not found: %v", err)
 		return "", "", err
 	}
+
+	// amount provided in msat, but Alby API currently only supports sats. Will get truncated to a whole sat value
+	var amountSat int64 = amount / 1000
+	// make sure amount is not converted to 0
+	if (amount > 0 && amountSat == 0) {
+		svc.Logger.WithFields(logrus.Fields{
+			"senderPubkey":    senderPubkey,
+			"amount":          amount,
+			"description":     description,
+			"descriptionHash": descriptionHash,
+			"expiry":          expiry,
+		}).Errorf("Value must be 1 sat or greater");
+		return "", "", errors.New("Value must be 1 sat or greater")
+	}
+
 	svc.Logger.WithFields(logrus.Fields{
 		"senderPubkey":    senderPubkey,
 		"amount":          amount,
@@ -110,7 +125,7 @@ func (svc *AlbyOAuthService) MakeInvoice(ctx context.Context, senderPubkey strin
 
 	body := bytes.NewBuffer([]byte{})
 	payload := &MakeInvoiceRequest{
-		Amount: amount,
+		Amount: amountSat,
 		Description: description,
 		DescriptionHash: descriptionHash,
 		// TODO: support expiry

handle_make_invoice_request.go

@@ -53,6 +53,21 @@ func (svc *Service) HandleMakeInvoiceEvent(ctx context.Context, request *Nip47Re
 		return nil, err
 	}
 
+	if makeInvoiceParams.Description != "" && makeInvoiceParams.DescriptionHash != "" {
+		svc.Logger.WithFields(logrus.Fields{
+			"eventId":   event.ID,
+			"eventKind": event.Kind,
+			"appId":     app.ID,
+		}).Errorf("Only one of description, description_hash can be provided")
+
+		return svc.createResponse(event, Nip47Response{
+			Error: &Nip47Error{
+				Code:    NIP_47_OTHER,
+				Message: "Only one of description, description_hash can be provided",
+			},
+		}, ss)
+	}
+
 	svc.Logger.WithFields(logrus.Fields{
 		"eventId":         event.ID,
 		"eventKind":       event.Kind,
@@ -63,6 +78,8 @@ func (svc *Service) HandleMakeInvoiceEvent(ctx context.Context, request *Nip47Re
 		"expiry":          makeInvoiceParams.Expiry,
 	}).Info("Making invoice")
 
+
+
 	invoice, paymentHash, err := svc.lnClient.MakeInvoice(ctx, event.PubKey, makeInvoiceParams.Amount, makeInvoiceParams.Description, makeInvoiceParams.DescriptionHash, makeInvoiceParams.Expiry)
 	if err != nil {
 		svc.Logger.WithFields(logrus.Fields{
@@ -92,7 +109,7 @@ func (svc *Service) HandleMakeInvoiceEvent(ctx context.Context, request *Nip47Re
 	nostrEvent.State = NOSTR_EVENT_STATE_HANDLER_EXECUTED
 	svc.db.Save(&nostrEvent)
 	return svc.createResponse(event, Nip47Response{
-		ResultType: NIP_47_GET_BALANCE_METHOD,
+		ResultType: NIP_47_MAKE_INVOICE_METHOD,
 		Result: responsePayload,
 	},
 	ss)

lnd.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"encoding/hex"
+	"errors"
 	"fmt"
 
 	"github.com/sirupsen/logrus"
@@ -46,7 +47,29 @@ func (svc *LNDService) GetBalance(ctx context.Context, senderPubkey string) (bal
 }
 
 func (svc *LNDService) MakeInvoice(ctx context.Context, senderPubkey string, amount int64, description string, descriptionHash string, expiry int64) (invoice string, paymentHash string, err error) {
-	return "", "", fmt.Errorf("not implemented")
+	var descriptionHashBytes []byte
+
+	if descriptionHash != "" {
+		descriptionHashBytes, err = hex.DecodeString(descriptionHash)
+
+		if err != nil || len(descriptionHashBytes) != 32 {
+			svc.Logger.WithFields(logrus.Fields{
+				"senderPubkey":    senderPubkey,
+				"amount":          amount,
+				"description":     description,
+				"descriptionHash": descriptionHash,
+				"expiry":          expiry,
+			}).Errorf("Invalid description hash")
+			return "", "", errors.New("Description hash must be 32 bytes hex")
+		}
+	}
+
+	resp, err := svc.client.AddInvoice(ctx, &lnrpc.Invoice{ValueMsat: amount, Memo: description, DescriptionHash: descriptionHashBytes, Expiry: expiry})
+	if err != nil {
+		return "", "", err
+	}
+
+	return resp.GetPaymentRequest(), hex.EncodeToString(resp.GetRHash()), nil
 }
 
 func (svc *LNDService) SendPaymentSync(ctx context.Context, senderPubkey, payReq string) (preimage string, err error) {

models.go

@@ -21,6 +21,7 @@ const (
 	NIP_47_ERROR_UNAUTHORIZED         = "UNAUTHORIZED"
 	NIP_47_ERROR_EXPIRED              = "EXPIRED"
 	NIP_47_ERROR_RESTRICTED           = "RESTRICTED"
+	NIP_47_OTHER                      = "OTHER"
 	NIP_47_CAPABILITIES               = "pay_invoice,get_balance"
 )
 

service.go

@@ -26,6 +26,7 @@ type Service struct {
 var supportedMethods = map[string]bool{
 	NIP_47_PAY_INVOICE_METHOD: true,
 	NIP_47_GET_BALANCE_METHOD: true,
+	NIP_47_MAKE_INVOICE_METHOD: true,
 }
 
 func (svc *Service) GetUser(c echo.Context) (user *User, err error) {

service_test.go

@@ -28,7 +28,6 @@ const nip47MakeInvoiceJson = `
 	"params": {
 		"amount": 1000,
 		"description": "[[\"text/identifier\",\"hello@getalby.com\"],[\"text/plain\",\"Sats for Alby\"]]",
-		"description_hash": "7da78494568d0c8afcd972ea5f5464d6f8d222025c04704e3d19c338ed61cd1f",
 		"expiry": 3600
 	}
 }