return invoice status in lightning client

cashu/cashu.go

@@ -173,7 +173,7 @@ var (
  ProofAlreadyUsedErr = Error{Detail: "proofs already used", Code: ProofsErrCode}
  InvalidProofErr = Error{Detail: "invalid proof", Code: ProofsErrCode}
  InputsBelowOutputs = Error{Detail: "amount of input proofs is below amount of outputs", Code: ProofsErrCode}
- MeltQuoteNotExistErr = Error{Detail: "melt quote does not exist", Code: QuoteErrCode}
+ QuoteNotExistErr  = Error{Detail: "quote does not exist", Code: QuoteErrCode}
  InsufficientProofsAmount = Error{Detail: "insufficient amount in proofs", Code: ProofsErrCode}
  InvalidKeysetProof = Error{Detail: "proof from an invalid keyset", Code: ProofsErrCode}
  InvalidSignatureRequest = Error{Detail: "requested signature from non-active keyset", Code: KeysetErrCode}

mint/lightning/lightning.go

@@ -12,7 +12,7 @@ const (
 // Client interface to interact with a Lightning backend
 type Client interface {
  CreateInvoice(amount uint64) (Invoice, error)
- InvoiceSettled(hash string) (bool, error)
+ InvoiceStatus(hash string) (Invoice, error)
  FeeReserve(amount uint64) uint64
  SendPayment(request string, amount uint64) (string, error)
 }
@@ -39,6 +39,7 @@ type Invoice struct {
  Id string // random id generated by mint
  PaymentRequest string
  PaymentHash string
+ Preimage string
  Settled bool
  Redeemed bool
  Amount uint64

mint/lightning/lnd.go

@@ -99,19 +99,26 @@ func (lnd *LndClient) CreateInvoice(amount uint64) (Invoice, error) {
  return invoice, nil
 }
 
-func (lnd *LndClient) InvoiceSettled(hash string) (bool, error) {
+func (lnd *LndClient) InvoiceStatus(hash string) (Invoice, error) {
  hashBytes, err := hex.DecodeString(hash)
  if err != nil {
- return false, errors.New("invalid hash provided")
+ return Invoice{}, errors.New("invalid hash provided")
  }
 
  paymentHashRequest := lnrpc.PaymentHash{RHash: hashBytes}
  lookupInvoiceResponse, err := lnd.grpcClient.LookupInvoice(context.Background(), &paymentHashRequest)
  if err != nil {
- return false, fmt.Errorf("error getting invoice status: %v", err)
+ return Invoice{}, err
  }
 
- return lookupInvoiceResponse.State == lnrpc.Invoice_SETTLED, nil
+ invoice := Invoice{
+ PaymentRequest: lookupInvoiceResponse.PaymentRequest,
+ PaymentHash: hash,
+ Settled: lookupInvoiceResponse.State == lnrpc.Invoice_SETTLED,
+ Amount: uint64(lookupInvoiceResponse.Value),
+ }
+
+ return invoice, nil
 }
 
 func (lnd *LndClient) FeeReserve(amount uint64) uint64 {

mint/mint.go

@@ -134,18 +134,25 @@ func (m *Mint) GetMintQuoteState(method, quoteId string) (nut04.PostMintQuoteBol
 
  invoice := m.db.GetInvoice(quoteId)
  if invoice == nil {
- return nut04.PostMintQuoteBolt11Response{}, cashu.InvoiceNotExistErr
+ return nut04.PostMintQuoteBolt11Response{}, cashu.QuoteNotExistErr
  }
 
  // check if the invoice has been paid
- settled, _ := m.LightningClient.InvoiceSettled(invoice.PaymentHash)
- if settled != invoice.Settled {
- invoice.Settled = settled
+ status, err := m.LightningClient.InvoiceStatus(invoice.PaymentHash)
+ if err != nil {
+ return nut04.PostMintQuoteBolt11Response{}, fmt.Errorf("error checking invoice status: %v", err)
+ }
+ if status.Settled && status.Settled != invoice.Settled {
+ invoice.Settled = status.Settled
  m.db.SaveInvoice(*invoice)
  }
 
- quoteState := nut04.PostMintQuoteBolt11Response{Quote: invoice.Id,
- Request: invoice.PaymentRequest, Paid: settled, Expiry: invoice.Expiry}
+ quoteState := nut04.PostMintQuoteBolt11Response{
+ Quote: invoice.Id,
+ Request: invoice.PaymentRequest,
+ Paid: invoice.Settled,
+ Expiry: invoice.Expiry,
+ }
  return quoteState, nil
 }
 
@@ -163,8 +170,11 @@ func (m *Mint) MintTokens(method, id string, blindedMessages cashu.BlindedMessag
 
  var blindedSignatures cashu.BlindedSignatures
 
- settled, _ := m.LightningClient.InvoiceSettled(invoice.PaymentHash)
- if settled {
+ status, err := m.LightningClient.InvoiceStatus(invoice.PaymentHash)
+ if err != nil {
+ return nil, fmt.Errorf("error checking invoice status: %v", err)
+ }
+ if status.Settled {
  if invoice.Redeemed {
  return nil, cashu.InvoiceTokensIssuedErr
  }
@@ -295,7 +305,7 @@ func (m *Mint) GetMeltQuoteState(method, quoteId string) (MeltQuote, error) {
 
  meltQuote := m.db.GetMeltQuote(quoteId)
  if meltQuote == nil {
- return MeltQuote{}, cashu.MeltQuoteNotExistErr
+ return MeltQuote{}, cashu.QuoteNotExistErr
  }
 
  return *meltQuote, nil
@@ -310,7 +320,7 @@ func (m *Mint) MeltTokens(method, quoteId string, proofs cashu.Proofs) (MeltQuot
 
  meltQuote := m.db.GetMeltQuote(quoteId)
  if meltQuote == nil {
- return MeltQuote{}, cashu.MeltQuoteNotExistErr
+ return MeltQuote{}, cashu.QuoteNotExistErr
  }
 
  proofsAmount := proofs.Amount()

mint/server.go

@@ -191,7 +191,7 @@ func (ms *MintServer) mintRequest(rw http.ResponseWriter, req *http.Request) {
  reqMintResponse, err := ms.mint.RequestMintQuote(method, mintReq.Amount, mintReq.Unit)
  if err != nil {
  cashuErr, ok := err.(*cashu.Error)
- // RequestMintQuote will return err from lightning backend if invoice
+ // note: RequestMintQuote will return err from lightning backend if invoice
  // generation fails. Log that err from backend but return generic response to request
  if ok && cashuErr.Code == cashu.InvoiceErrCode {
  ms.writeErr(rw, req, cashu.StandardErr, cashuErr.Error())
@@ -218,6 +218,12 @@ func (ms *MintServer) mintQuoteState(rw http.ResponseWriter, req *http.Request)
 
  mintQuoteStateResponse, err := ms.mint.GetMintQuoteState(method, quoteId)
  if err != nil {
+ // if error is from lnd, log it but throw generic response
+ _, ok := err.(*cashu.Error)
+ if !ok {
+ ms.writeErr(rw, req, cashu.StandardErr, err.Error())
+ }
+
  ms.writeErr(rw, req, err)
  return
  }
@@ -243,6 +249,12 @@ func (ms *MintServer) mintTokensRequest(rw http.ResponseWriter, req *http.Reques
 
  blindedSignatures, err := ms.mint.MintTokens(method, mintReq.Quote, mintReq.Outputs)
  if err != nil {
+ // if error is from lnd, log it but throw generic response
+ _, ok := err.(*cashu.Error)
+ if !ok {
+ ms.writeErr(rw, req, cashu.StandardErr, err.Error())
+ }
+
  ms.writeErr(rw, req, err)
  return
  }