Add itest oracle harness

itest/log.go

@@ -0,0 +1,24 @@
+package itest
+
+import (
+	"github.com/btcsuite/btclog"
+	"github.com/lightningnetwork/lnd/build"
+)
+
+const Subsystem = "ITST"
+
+// log is a logger that is initialized with no output filters. This means the
+// package will not perform any logging by default until the caller requests it.
+var log btclog.Logger
+
+// The default amount of logging is none.
+func init() {
+	UseLogger(build.NewSubLogger(Subsystem, nil))
+}
+
+// UseLogger uses a specified Logger to output package logging info.
+// This should be used in preference to SetLogWriter if the caller is also
+// using btclog.
+func UseLogger(logger btclog.Logger) {
+	log = logger
+}

itest/oracle_harness.go

@@ -0,0 +1,325 @@
+package itest
+
+import (
+	"context"
+	"crypto/tls"
+	"encoding/hex"
+	"fmt"
+	"net"
+	"testing"
+	"time"
+
+	"github.com/btcsuite/btcd/btcec/v2"
+	"github.com/lightninglabs/taproot-assets/asset"
+	"github.com/lightninglabs/taproot-assets/rfqmath"
+	"github.com/lightninglabs/taproot-assets/rfqmsg"
+	oraclerpc "github.com/lightninglabs/taproot-assets/taprpc/priceoraclerpc"
+	"github.com/lightningnetwork/lnd/cert"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials"
+)
+
+// oracleHarness is a basic integration test RPC price oracle server harness.
+type oracleHarness struct {
+	oraclerpc.UnimplementedPriceOracleServer
+
+	listenAddr string
+
+	grpcListener net.Listener
+	grpcServer   *grpc.Server
+
+	// bidPrices is a map used internally by the oracle harness to store bid
+	// prices for certain assets. We use the asset specifier string as a
+	// unique identifier, since it will either contain an asset ID or a
+	// group key.
+	bidPrices map[string]rfqmath.BigIntFixedPoint
+
+	// askPrices is a map used internally by the oracle harness to store ask
+	// prices for certain assets. We use the asset specifier string as a
+	// unique identifier, since it will either contain an asset ID or a
+	// group key.
+	askPrices map[string]rfqmath.BigIntFixedPoint
+}
+
+// newOracleHarness returns a new oracle harness instance that is set to listen
+// on the provided address.
+func newOracleHarness(listenAddr string) *oracleHarness {
+	return &oracleHarness{
+		listenAddr: listenAddr,
+		bidPrices:  make(map[string]rfqmath.BigIntFixedPoint),
+		askPrices:  make(map[string]rfqmath.BigIntFixedPoint),
+	}
+}
+
+// setPrice sets the target bid and ask price for the provided specifier.
+func (o *oracleHarness) setPrice(specifier asset.Specifier, bidPrice,
+	askPrice rfqmath.BigIntFixedPoint) {
+
+	o.bidPrices[specifier.String()] = bidPrice
+	o.askPrices[specifier.String()] = askPrice
+}
+
+// start runs the oracle harness.
+func (o *oracleHarness) start(t *testing.T) {
+	// Start the mock RPC price oracle service.
+	//
+	// Generate self-signed certificate. This allows us to use TLS for the
+	// gRPC server.
+	tlsCert, err := generateSelfSignedCert()
+	require.NoError(t, err)
+
+	// Create the gRPC server with TLS
+	transportCredentials := credentials.NewTLS(&tls.Config{
+		Certificates: []tls.Certificate{tlsCert},
+	})
+	o.grpcServer = grpc.NewServer(grpc.Creds(transportCredentials))
+
+	serviceAddr := fmt.Sprintf("rfqrpc://%s", o.listenAddr)
+	log.Infof("Starting RPC price oracle service at address: %s\n",
+		serviceAddr)
+
+	oraclerpc.RegisterPriceOracleServer(o.grpcServer, o)
+
+	go func() {
+		var err error
+		o.grpcListener, err = net.Listen("tcp", o.listenAddr)
+		if err != nil {
+			log.Errorf("Error oracle listening: %v", err)
+			return
+		}
+		if err := o.grpcServer.Serve(o.grpcListener); err != nil {
+			log.Errorf("Error oracle serving: %v", err)
+		}
+	}()
+}
+
+// stop terminates the oracle harness.
+func (o *oracleHarness) stop() {
+	if o.grpcServer != nil {
+		o.grpcServer.Stop()
+	}
+	if o.grpcListener != nil {
+		_ = o.grpcListener.Close()
+	}
+}
+
+// getAssetRates returns the asset rates for a given transaction type.
+func (o *oracleHarness) getAssetRates(specifier asset.Specifier,
+	transactionType oraclerpc.TransactionType) (oraclerpc.AssetRates,
+	error) {
+
+	// Determine the rate based on the transaction type.
+	var subjectAssetRate rfqmath.BigIntFixedPoint
+	if transactionType == oraclerpc.TransactionType_PURCHASE {
+		rate, ok := o.bidPrices[specifier.String()]
+		if !ok {
+			return oraclerpc.AssetRates{}, fmt.Errorf("purchase "+
+				"price not found for %s", specifier.String())
+		}
+		subjectAssetRate = rate
+	} else {
+		rate, ok := o.askPrices[specifier.String()]
+		if !ok {
+			return oraclerpc.AssetRates{}, fmt.Errorf("sale "+
+				"price not found for %s", specifier.String())
+		}
+		subjectAssetRate = rate
+	}
+
+	// Marshal subject asset rate to RPC format.
+	rpcSubjectAssetToBtcRate, err := oraclerpc.MarshalBigIntFixedPoint(
+		subjectAssetRate,
+	)
+	if err != nil {
+		return oraclerpc.AssetRates{}, err
+	}
+
+	// Marshal payment asset rate to RPC format.
+	rpcPaymentAssetToBtcRate, err := oraclerpc.MarshalBigIntFixedPoint(
+		rfqmsg.MilliSatPerBtc,
+	)
+	if err != nil {
+		return oraclerpc.AssetRates{}, err
+	}
+
+	expiry := time.Now().Add(5 * time.Minute).Unix()
+	return oraclerpc.AssetRates{
+		SubjectAssetRate: rpcSubjectAssetToBtcRate,
+		PaymentAssetRate: rpcPaymentAssetToBtcRate,
+		ExpiryTimestamp:  uint64(expiry),
+	}, nil
+}
+
+// QueryAssetRates queries the asset rates for a given transaction type, subject
+// asset, and payment asset. An asset rate is the number of asset units per
+// BTC.
+//
+// Example use case:
+//
+// Alice is trying to pay an invoice by spending an asset. Alice therefore
+// requests that Bob (her asset channel counterparty) purchase the asset from
+// her. Bob's payment, in BTC, will pay the invoice.
+//
+// Alice requests a bid quote from Bob. Her request includes an asset rates hint
+// (ask). Alice obtains the asset rates hint by calling this endpoint. She sets:
+// - `SubjectAsset` to the asset she is trying to sell.
+// - `SubjectAssetMaxAmount` to the max channel asset outbound.
+// - `PaymentAsset` to BTC.
+// - `TransactionType` to SALE.
+// - `AssetRateHint` to nil.
+//
+// Bob calls this endpoint to get the bid quote asset rates that he will send as
+// a response to Alice's request. He sets:
+// - `SubjectAsset` to the asset that Alice is trying to sell.
+// - `SubjectAssetMaxAmount` to the value given in Alice's quote request.
+// - `PaymentAsset` to BTC.
+// - `TransactionType` to PURCHASE.
+// - `AssetRateHint` to the value given in Alice's quote request.
+func (o *oracleHarness) QueryAssetRates(_ context.Context,
+	req *oraclerpc.QueryAssetRatesRequest) (
+	*oraclerpc.QueryAssetRatesResponse, error) {
+
+	// Ensure that the payment asset is BTC. We only support BTC as the
+	// payment asset in this example.
+	if !oraclerpc.IsAssetBtc(req.PaymentAsset) {
+		log.Infof("Payment asset is not BTC: %v", req.PaymentAsset)
+
+		return &oraclerpc.QueryAssetRatesResponse{
+			Result: &oraclerpc.QueryAssetRatesResponse_Error{
+				Error: &oraclerpc.QueryAssetRatesErrResponse{
+					Message: "unsupported payment asset, " +
+						"only BTC is supported",
+				},
+			},
+		}, nil
+	}
+
+	// Ensure that the subject asset is set correctly.
+	specifier, err := parseSubjectAsset(req.SubjectAsset)
+	if err != nil {
+		log.Errorf("Error parsing subject asset: %v", err)
+		return nil, fmt.Errorf("error parsing subject asset: %w", err)
+	}
+
+	_, hasPurchase := o.bidPrices[specifier.String()]
+	_, hasSale := o.askPrices[specifier.String()]
+
+	log.Infof("Have for %s, purchase=%v, sale=%v", specifier.String(),
+		hasPurchase, hasSale)
+
+	// Ensure that the subject asset is supported.
+	if !hasPurchase || !hasSale {
+		log.Infof("Unsupported subject specifier: %v\n",
+			req.SubjectAsset)
+
+		return &oraclerpc.QueryAssetRatesResponse{
+			Result: &oraclerpc.QueryAssetRatesResponse_Error{
+				Error: &oraclerpc.QueryAssetRatesErrResponse{
+					Message: "unsupported subject asset",
+				},
+			},
+		}, nil
+	}
+
+	assetRates, err := o.getAssetRates(specifier, req.TransactionType)
+	if err != nil {
+		return nil, err
+	}
+
+	log.Infof("QueryAssetRates returning rates (subject_asset_rate=%v, "+
+		"payment_asset_rate=%v)", assetRates.SubjectAssetRate,
+		assetRates.PaymentAssetRate)
+
+	return &oraclerpc.QueryAssetRatesResponse{
+		Result: &oraclerpc.QueryAssetRatesResponse_Ok{
+			Ok: &oraclerpc.QueryAssetRatesOkResponse{
+				AssetRates: &assetRates,
+			},
+		},
+	}, nil
+}
+
+// parseSubjectAsset parses the subject asset from the given asset specifier.
+func parseSubjectAsset(subjectAsset *oraclerpc.AssetSpecifier) (asset.Specifier,
+	error) {
+
+	// Ensure that the subject asset is set.
+	if subjectAsset == nil {
+		return asset.Specifier{}, fmt.Errorf("subject asset is not " +
+			"set (nil)")
+	}
+
+	// Check the subject asset bytes if set.
+	var specifier asset.Specifier
+	switch {
+	case len(subjectAsset.GetAssetId()) > 0:
+		var assetID asset.ID
+		copy(assetID[:], subjectAsset.GetAssetId())
+		specifier = asset.NewSpecifierFromId(assetID)
+
+	case len(subjectAsset.GetAssetIdStr()) > 0:
+		assetIDBytes, err := hex.DecodeString(
+			subjectAsset.GetAssetIdStr(),
+		)
+		if err != nil {
+			return asset.Specifier{}, fmt.Errorf("error decoding "+
+				"asset ID hex string: %w", err)
+		}
+
+		var assetID asset.ID
+		copy(assetID[:], assetIDBytes)
+		specifier = asset.NewSpecifierFromId(assetID)
+
+	case len(subjectAsset.GetGroupKey()) > 0:
+		groupKeyBytes := subjectAsset.GetGroupKey()
+		groupKey, err := btcec.ParsePubKey(groupKeyBytes)
+		if err != nil {
+			return asset.Specifier{}, fmt.Errorf("error decoding "+
+				"asset group key: %w", err)
+		}
+
+		specifier = asset.NewSpecifierFromGroupKey(*groupKey)
+
+	case len(subjectAsset.GetGroupKeyStr()) > 0:
+		groupKeyBytes, err := hex.DecodeString(
+			subjectAsset.GetGroupKeyStr(),
+		)
+		if err != nil {
+			return asset.Specifier{}, fmt.Errorf("error decoding "+
+				" asset group key string: %w", err)
+		}
+
+		groupKey, err := btcec.ParsePubKey(groupKeyBytes)
+		if err != nil {
+			return asset.Specifier{}, fmt.Errorf("error decoding "+
+				"asset group key: %w", err)
+		}
+
+		specifier = asset.NewSpecifierFromGroupKey(*groupKey)
+
+	default:
+		return asset.Specifier{}, fmt.Errorf("subject asset " +
+			"specifier is empty")
+	}
+
+	return specifier, nil
+}
+
+// generateSelfSignedCert generates a self-signed TLS certificate and private
+// key.
+func generateSelfSignedCert() (tls.Certificate, error) {
+	certBytes, keyBytes, err := cert.GenCertPair(
+		"itest price oracle", nil, nil, false, 24*time.Hour,
+	)
+	if err != nil {
+		return tls.Certificate{}, err
+	}
+
+	tlsCert, err := tls.X509KeyPair(certBytes, keyBytes)
+	if err != nil {
+		return tls.Certificate{}, err
+	}
+
+	return tlsCert, nil
+}