rpcutils: move price oracle gRPC marshal functionality from taprpc

Move price oracle related gRPC marshalling functionality from the
taprpc package to the rpcutils package as preparation for future
modularization.

Author: ffranr

itest/oracle_harness.go

@@ -13,6 +13,7 @@ import (
 	"github.com/lightninglabs/taproot-assets/asset"
 	"github.com/lightninglabs/taproot-assets/rfqmath"
 	"github.com/lightninglabs/taproot-assets/rfqmsg"
+	"github.com/lightninglabs/taproot-assets/rpcutils"
 	oraclerpc "github.com/lightninglabs/taproot-assets/taprpc/priceoraclerpc"
 	"github.com/lightningnetwork/lnd/cert"
 	"github.com/stretchr/testify/require"
@@ -128,15 +129,15 @@ func (o *oracleHarness) getAssetRates(specifier asset.Specifier,
 	}
 
 	// Marshal subject asset rate to RPC format.
-	rpcSubjectAssetToBtcRate, err := oraclerpc.MarshalBigIntFixedPoint(
+	rpcSubjectAssetToBtcRate, err := rpcutils.MarshalBigIntFixedPoint(
 		subjectAssetRate,
 	)
 	if err != nil {
 		return oraclerpc.AssetRates{}, err
 	}
 
 	// Marshal payment asset rate to RPC format.
-	rpcPaymentAssetToBtcRate, err := oraclerpc.MarshalBigIntFixedPoint(
+	rpcPaymentAssetToBtcRate, err := rpcutils.MarshalBigIntFixedPoint(
 		rfqmsg.MilliSatPerBtc,
 	)
 	if err != nil {
@@ -182,7 +183,7 @@ func (o *oracleHarness) QueryAssetRates(_ context.Context,
 
 	// Ensure that the payment asset is BTC. We only support BTC as the
 	// payment asset in this example.
-	if !oraclerpc.IsAssetBtc(req.PaymentAsset) {
+	if !rpcutils.IsAssetBtc(req.PaymentAsset) {
 		log.Infof("Payment asset is not BTC: %v", req.PaymentAsset)
 
 		return &oraclerpc.QueryAssetRatesResponse{

rfq/oracle.go

@@ -11,6 +11,7 @@ import (
 	"github.com/lightninglabs/taproot-assets/asset"
 	"github.com/lightninglabs/taproot-assets/fn"
 	"github.com/lightninglabs/taproot-assets/rfqmsg"
+	"github.com/lightninglabs/taproot-assets/rpcutils"
 	oraclerpc "github.com/lightninglabs/taproot-assets/taprpc/priceoraclerpc"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"google.golang.org/grpc"
@@ -203,7 +204,7 @@ func (r *RpcPriceOracle) QueryAskPrice(ctx context.Context,
 
 	// Construct the RPC asset rates hint.
 	rpcAssetRatesHint, err := fn.MapOptionZ(
-		assetRateHint, oraclerpc.MarshalAssetRates,
+		assetRateHint, rpcutils.MarshalAssetRates,
 	).Unpack()
 	if err != nil {
 		return nil, err
@@ -242,7 +243,7 @@ func (r *RpcPriceOracle) QueryAskPrice(ctx context.Context,
 		}
 
 		// Unmarshal the subject asset to BTC rate.
-		rate, err := oraclerpc.UnmarshalFixedPoint(
+		rate, err := rpcutils.UnmarshalFixedPoint(
 			result.Ok.AssetRates.SubjectAssetRate,
 		)
 		if err != nil {
@@ -299,7 +300,7 @@ func (r *RpcPriceOracle) QueryBidPrice(ctx context.Context,
 
 	// Construct the RPC asset rates hint.
 	rpcAssetRatesHint, err := fn.MapOptionZ(
-		assetRateHint, oraclerpc.MarshalAssetRates,
+		assetRateHint, rpcutils.MarshalAssetRates,
 	).Unpack()
 	if err != nil {
 		return nil, err
@@ -333,7 +334,7 @@ func (r *RpcPriceOracle) QueryBidPrice(ctx context.Context,
 		}
 
 		// Unmarshal the subject asset to BTC rate.
-		rate, err := oraclerpc.UnmarshalFixedPoint(
+		rate, err := rpcutils.UnmarshalFixedPoint(
 			result.Ok.AssetRates.SubjectAssetRate,
 		)
 		if err != nil {

rfq/oracle_test.go

@@ -13,6 +13,7 @@ import (
 	"github.com/lightninglabs/taproot-assets/internal/test"
 	"github.com/lightninglabs/taproot-assets/rfqmath"
 	"github.com/lightninglabs/taproot-assets/rfqmsg"
+	"github.com/lightninglabs/taproot-assets/rpcutils"
 	"github.com/lightninglabs/taproot-assets/taprpc/priceoraclerpc"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/stretchr/testify/require"
@@ -41,7 +42,7 @@ func (p *mockRpcPriceOracleServer) QueryAssetRates(_ context.Context,
 	subjectAssetRate := rfqmath.NewBigIntFixedPoint(testAssetRate, 3)
 
 	// Marshal the subject asset rate to a fixed point.
-	subjectAssetFp, err := priceoraclerpc.MarshalBigIntFixedPoint(
+	subjectAssetFp, err := rpcutils.MarshalBigIntFixedPoint(
 		subjectAssetRate,
 	)
 	if err != nil {

taprpc/priceoraclerpc/marshal.go renamed to rpcutils/price_oracle_marshal.go

@@ -1,4 +1,4 @@
-package priceoraclerpc
+package rpcutils
 
 import (
 	"bytes"
@@ -8,12 +8,13 @@ import (
 
 	"github.com/lightninglabs/taproot-assets/rfqmath"
 	"github.com/lightninglabs/taproot-assets/rfqmsg"
+	"github.com/lightninglabs/taproot-assets/taprpc/priceoraclerpc"
 	lfn "github.com/lightningnetwork/lnd/fn/v2"
 )
 
 // IsAssetBtc is a helper function that returns true if the given asset
 // specifier represents BTC, and false otherwise.
-func IsAssetBtc(assetSpecifier *AssetSpecifier) bool {
+func IsAssetBtc(assetSpecifier *priceoraclerpc.AssetSpecifier) bool {
 	// An unset asset specifier does not represent BTC.
 	if assetSpecifier == nil {
 		return false
@@ -49,40 +50,46 @@ func IsAssetBtc(assetSpecifier *AssetSpecifier) bool {
 // MarshalAssetRates converts an asset rate to an RPC AssetRates.
 // The OK result has a pointer type so that it is nil if there is an error.
 // NOTE: The payment asset is assumed to be BTC.
-func MarshalAssetRates(assetRate rfqmsg.AssetRate) lfn.Result[*AssetRates] {
+func MarshalAssetRates(
+	assetRate rfqmsg.AssetRate) lfn.Result[*priceoraclerpc.AssetRates] {
+
 	// Marshal the subject asset rate.
 	subjectAssetRate, err := MarshalBigIntFixedPoint(assetRate.Rate)
 	if err != nil {
-		return lfn.Err[*AssetRates](err)
+		return lfn.Err[*priceoraclerpc.AssetRates](err)
 	}
 
 	// Marshal the payment asset rate. For now, we only support BTC as the
 	// payment asset.
 	paymentAssetRate, err := MarshalBigIntFixedPoint(rfqmsg.MilliSatPerBtc)
 	if err != nil {
-		return lfn.Err[*AssetRates](err)
+		return lfn.Err[*priceoraclerpc.AssetRates](err)
 	}
 
 	// Compute an expiry unix timestamp from the given asset rate expiry.
 	expiryTimestamp := uint64(assetRate.Expiry.Unix())
 
-	return lfn.Ok[*AssetRates](&AssetRates{
+	return lfn.Ok[*priceoraclerpc.AssetRates](&priceoraclerpc.AssetRates{
 		SubjectAssetRate: subjectAssetRate,
 		PaymentAssetRate: paymentAssetRate,
 		ExpiryTimestamp:  expiryTimestamp,
 	})
 }
 
 // MarshalBigIntFixedPoint converts a BigIntFixedPoint to an RPC FixedPoint.
-func MarshalBigIntFixedPoint(fp rfqmath.BigIntFixedPoint) (*FixedPoint, error) {
-	return &FixedPoint{
+func MarshalBigIntFixedPoint(
+	fp rfqmath.BigIntFixedPoint) (*priceoraclerpc.FixedPoint, error) {
+
+	return &priceoraclerpc.FixedPoint{
 		Coefficient: fp.Coefficient.String(),
 		Scale:       uint32(fp.Scale),
 	}, nil
 }
 
 // UnmarshalFixedPoint converts an RPC FixedPoint to a BigIntFixedPoint.
-func UnmarshalFixedPoint(fp *FixedPoint) (*rfqmath.BigIntFixedPoint, error) {
+func UnmarshalFixedPoint(
+	fp *priceoraclerpc.FixedPoint) (*rfqmath.BigIntFixedPoint, error) {
+
 	// Return an error is the scale component of the fixed point is greater
 	// than the max value of uint8.
 	if fp.Scale > 255 {

taprpc/priceoraclerpc/marshal_test.go renamed to rpcutils/price_oracle_marshal_test.go

@@ -1,17 +1,18 @@
-package priceoraclerpc
+package rpcutils
 
 import (
 	"encoding/hex"
 	"testing"
 
+	"github.com/lightninglabs/taproot-assets/taprpc/priceoraclerpc"
 	"github.com/stretchr/testify/require"
 )
 
 // isAssetBtcTC is a test case for the IsAssetBtc function.
 type isAssetBtcTC struct {
 	testName string
 
-	assetSpecifier *AssetSpecifier
+	assetSpecifier *priceoraclerpc.AssetSpecifier
 	expected       bool
 }
 
@@ -32,13 +33,13 @@ func TestIsAssetBtc(t *testing.T) {
 		},
 		{
 			testName:       "empty asset specifier",
-			assetSpecifier: &AssetSpecifier{},
+			assetSpecifier: &priceoraclerpc.AssetSpecifier{},
 			expected:       false,
 		},
 		{
 			testName: "asset specifier with zero asset ID bytes",
-			assetSpecifier: &AssetSpecifier{
-				Id: &AssetSpecifier_AssetId{
+			assetSpecifier: &priceoraclerpc.AssetSpecifier{
+				Id: &priceoraclerpc.AssetSpecifier_AssetId{
 					AssetId: zeroAssetId[:],
 				},
 			},
@@ -47,53 +48,53 @@ func TestIsAssetBtc(t *testing.T) {
 		{
 			testName: "asset specifier with incorrect length " +
 				"zero asset ID bytes",
-			assetSpecifier: &AssetSpecifier{
-				Id: &AssetSpecifier_AssetId{
+			assetSpecifier: &priceoraclerpc.AssetSpecifier{
+				Id: &priceoraclerpc.AssetSpecifier_AssetId{
 					AssetId: []byte{0, 0, 0},
 				},
 			},
 			expected: false,
 		},
 		{
 			testName: "asset specifier with empty asset ID bytes",
-			assetSpecifier: &AssetSpecifier{
-				Id: &AssetSpecifier_AssetId{
+			assetSpecifier: &priceoraclerpc.AssetSpecifier{
+				Id: &priceoraclerpc.AssetSpecifier_AssetId{
 					AssetId: []byte{},
 				},
 			},
 			expected: false,
 		},
 		{
 			testName: "asset specifier with zero asset ID string",
-			assetSpecifier: &AssetSpecifier{
-				Id: &AssetSpecifier_AssetIdStr{
+			assetSpecifier: &priceoraclerpc.AssetSpecifier{
+				Id: &priceoraclerpc.AssetSpecifier_AssetIdStr{
 					AssetIdStr: zeroAssetHexStr,
 				},
 			},
 			expected: true,
 		},
 		{
 			testName: "asset specifier with empty asset ID string",
-			assetSpecifier: &AssetSpecifier{
-				Id: &AssetSpecifier_AssetIdStr{
+			assetSpecifier: &priceoraclerpc.AssetSpecifier{
+				Id: &priceoraclerpc.AssetSpecifier_AssetIdStr{
 					AssetIdStr: "",
 				},
 			},
 			expected: false,
 		},
 		{
 			testName: "asset specifier with set group key bytes",
-			assetSpecifier: &AssetSpecifier{
-				Id: &AssetSpecifier_GroupKey{
+			assetSpecifier: &priceoraclerpc.AssetSpecifier{
+				Id: &priceoraclerpc.AssetSpecifier_GroupKey{
 					GroupKey: []byte{0, 0, 0},
 				},
 			},
 			expected: false,
 		},
 		{
 			testName: "asset specifier with set group key string",
-			assetSpecifier: &AssetSpecifier{
-				Id: &AssetSpecifier_GroupKeyStr{
+			assetSpecifier: &priceoraclerpc.AssetSpecifier{
+				Id: &priceoraclerpc.AssetSpecifier_GroupKeyStr{
 					GroupKeyStr: "test-group-key",
 				},
 			},