rpc: refactor obtaining an RFQ send quote into new method

rpcserver.go

@@ -6989,6 +6989,65 @@ func (r *rpcServer) EncodeCustomRecords(_ context.Context,
 	}
 }
 
+// fetchSendRfqQuote fetches a sell quote from the RFQ manager to fulfill an
+// invoice with the given set of params.
+func (r *rpcServer) fetchSendRfqQuote(ctx context.Context, assetID asset.ID,
+	invoiceAmt lnwire.MilliSatoshi, peerPubKey *route.Vertex,
+	expiryTimestamp time.Time) (*rfqrpc.PeerAcceptedSellQuote, error) {
+
+	// We can now query the asset channels we have.
+	assetChan, err := r.rfqChannel(ctx, assetID, peerPubKey)
+	if err != nil {
+		return nil, fmt.Errorf("error finding asset channel to "+
+			"use: %w", err)
+	}
+
+	// Even if the user didn't specify the peer public key before, we
+	// definitely know it now. So let's make sure it's always set.
+	peerPubKey = &assetChan.channelInfo.PubKeyBytes
+
+	sendQuote, err := r.AddAssetSellOrder(
+		ctx, &rfqrpc.AddAssetSellOrderRequest{
+			AssetSpecifier: &rfqrpc.AssetSpecifier{
+				Id: &rfqrpc.AssetSpecifier_AssetId{
+					AssetId: assetID[:],
+				},
+			},
+			PaymentMaxAmt: uint64(invoiceAmt),
+			Expiry:        uint64(expiryTimestamp.Unix()),
+			PeerPubKey:    peerPubKey[:],
+			TimeoutSeconds: uint32(
+				rfq.DefaultTimeout.Seconds(),
+			),
+		},
+	)
+	if err != nil {
+		return nil, fmt.Errorf("error adding sell order: %w", err)
+	}
+
+	var acceptedQuote *rfqrpc.PeerAcceptedSellQuote
+	switch r := sendQuote.Response.(type) {
+	case *rfqrpc.AddAssetSellOrderResponse_AcceptedQuote:
+		acceptedQuote = r.AcceptedQuote
+
+	case *rfqrpc.AddAssetSellOrderResponse_InvalidQuote:
+		return nil, fmt.Errorf("peer %v sent back an invalid "+
+			"quote, status: %v", r.InvalidQuote.Peer,
+			r.InvalidQuote.Status.String())
+
+	case *rfqrpc.AddAssetSellOrderResponse_RejectedQuote:
+		return nil, fmt.Errorf("peer %v rejected the quote, code: "+
+			"%v, error message: %v", r.RejectedQuote.Peer,
+			r.RejectedQuote.ErrorCode,
+			r.RejectedQuote.ErrorMessage)
+
+	default:
+		return nil, fmt.Errorf("unexpected response type: %T", r)
+	}
+
+	return acceptedQuote, nil
+}
+
 // SendPayment is a wrapper around lnd's routerrpc.SendPaymentV2 RPC method
 // with asset specific parameters. It allows RPC users to send asset keysend
 // payments (direct payments) or payments to an invoice with a specified asset
@@ -7113,18 +7172,6 @@ func (r *rpcServer) SendPayment(req *tchrpc.SendPaymentRequest,
 			peerPubKey = &parsedKey
 		}
 
-		// We can now query the asset channels we have.
-		assetChan, err := r.rfqChannel(ctx, assetID, peerPubKey)
-		if err != nil {
-			return fmt.Errorf("error finding asset channel to "+
-				"use: %w", err)
-		}
-
-		// Even if the user didn't specify the peer public key before,
-		// we definitely know it now. So let's make sure it's always
-		// set.
-		peerPubKey = &assetChan.channelInfo.PubKeyBytes
-
 		// paymentMaxAmt is the maximum amount that the counterparty is
 		// expected to pay. This is the amount that the invoice is
 		// asking for plus the fee limit in milli-satoshis.
@@ -7157,43 +7204,12 @@ func (r *rpcServer) SendPayment(req *tchrpc.SendPaymentRequest,
 		paymentMaxAmt += feeLimit
 
 		expiryTimestamp := invoice.Timestamp.Add(invoice.Expiry())
-		resp, err := r.AddAssetSellOrder(
-			ctx, &rfqrpc.AddAssetSellOrderRequest{
-				AssetSpecifier: &rfqrpc.AssetSpecifier{
-					Id: &rfqrpc.AssetSpecifier_AssetId{
-						AssetId: assetID[:],
-					},
-				},
-				PaymentMaxAmt: uint64(paymentMaxAmt),
-				Expiry:        uint64(expiryTimestamp.Unix()),
-				PeerPubKey:    peerPubKey[:],
-				TimeoutSeconds: uint32(
-					rfq.DefaultTimeout.Seconds(),
-				),
-			},
+		acceptedQuote, err := r.fetchSendRfqQuote(
+			ctx, assetID, paymentMaxAmt, peerPubKey,
+			expiryTimestamp,
 		)
 		if err != nil {
-			return fmt.Errorf("error adding sell order: %w", err)
-		}
-
-		var acceptedQuote *rfqrpc.PeerAcceptedSellQuote
-		switch r := resp.Response.(type) {
-		case *rfqrpc.AddAssetSellOrderResponse_AcceptedQuote:
-			acceptedQuote = r.AcceptedQuote
-
-		case *rfqrpc.AddAssetSellOrderResponse_InvalidQuote:
-			return fmt.Errorf("peer %v sent back an invalid "+
-				"quote, status: %v", r.InvalidQuote.Peer,
-				r.InvalidQuote.Status.String())
-
-		case *rfqrpc.AddAssetSellOrderResponse_RejectedQuote:
-			return fmt.Errorf("peer %v rejected the quote, code: "+
-				"%v, error message: %v", r.RejectedQuote.Peer,
-				r.RejectedQuote.ErrorCode,
-				r.RejectedQuote.ErrorMessage)
-
-		default:
-			return fmt.Errorf("unexpected response type: %T", r)
+			return fmt.Errorf("error sending RFQ quote: %w", err)
 		}
 
 		// Send out the information about the quote on the stream.