liquid: assume everyone else supports CT discount

Assume support for all peerswap CT discounts with protocol version up. Remove the previous Ask forgiveness not permission approach, and return an error if CT discount is not supported.
ElementsProject · Aug 31, 2024 · cdc6211 · cdc6211
1 parent 065b87c
commit cdc6211
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Showing 2 changed files with 16 additions and 54 deletions.
diff --git a/lwk/lwkwallet.go b/lwk/lwkwallet.go
@@ -161,6 +161,7 @@ func (r *LWKRpcWallet) CreateAndBroadcastTransaction(swapParams *swap.OpeningPar
 	ctx, cancel := context.WithTimeout(context.Background(), defaultContextTimeout)
 	defer cancel()
 	feerate := r.getFeeSatPerVByte(ctx).getValue() * kb
+	// todo: There will be an option in the tx builder to enable the discount.
 	fundedTx, err := r.lwkClient.send(ctx, &sendRequest{
 		Addressees: []*unvalidatedAddressee{
 			{

diff --git a/onchain/liquid.go b/onchain/liquid.go
@@ -85,19 +85,7 @@ func (l *LiquidOnChain) CreateOpeningTransaction(swapParams *swap.OpeningParams)
 const feeAmountPlaceholder = uint64(500)
 
 func (l *LiquidOnChain) CreatePreimageSpendingTransaction(swapParams *swap.OpeningParams, claimParams *swap.ClaimParams) (string, string, string, error) {
-	fee, err := l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindPreimageSpending, true)))
-	if err != nil {
-		log.Infof("error getting fee %v", err)
-		fee = feeAmountPlaceholder
-	}
-	txId, txHex, newAddr, err := l.createPreimageSpendingTransaction(swapParams, claimParams, fee)
-	if err == nil {
-		return txId, txHex, newAddr, nil
-	}
-	if !errors.Is(err, wallet.MinRelayFeeNotMetError) {
-		return "", "", "", err
-	}
-	fee, err = l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindPreimageSpending, false)))
+	fee, err := l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindPreimageSpending)))
 	if err != nil {
 		log.Infof("error getting fee %v", err)
 		fee = feeAmountPlaceholder
@@ -142,19 +130,7 @@ func (l *LiquidOnChain) createPreimageSpendingTransaction(swapParams *swap.Openi
 }
 
 func (l *LiquidOnChain) CreateCsvSpendingTransaction(swapParams *swap.OpeningParams, claimParams *swap.ClaimParams) (txId, txHex, address string, error error) {
-	fee, err := l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindPreimageSpending, true)))
-	if err != nil {
-		log.Infof("error getting fee %v", err)
-		fee = feeAmountPlaceholder
-	}
-	txId, txHex, newAddr, err := l.createCsvSpendingTransaction(swapParams, claimParams, fee)
-	if err == nil {
-		return txId, txHex, newAddr, nil
-	}
-	if !errors.Is(err, wallet.MinRelayFeeNotMetError) {
-		return "", "", "", err
-	}
-	fee, err = l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindPreimageSpending, false)))
+	fee, err := l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindPreimageSpending)))
 	if err != nil {
 		log.Infof("error getting fee %v", err)
 		fee = feeAmountPlaceholder
@@ -185,19 +161,7 @@ func (l *LiquidOnChain) createCsvSpendingTransaction(swapParams *swap.OpeningPar
 }
 
 func (l *LiquidOnChain) CreateCoopSpendingTransaction(swapParams *swap.OpeningParams, claimParams *swap.ClaimParams, takerSigner swap.Signer) (txId, txHex, address string, error error) {
-	fee, err := l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindCoop, true)))
-	if err != nil {
-		log.Infof("error getting fee %v", err)
-		fee = feeAmountPlaceholder
-	}
-	txId, txHex, newAddr, err := l.createCoopSpendingTransaction(swapParams, claimParams, takerSigner, fee)
-	if err == nil {
-		return txId, txHex, newAddr, nil
-	}
-	if !errors.Is(err, wallet.MinRelayFeeNotMetError) {
-		return "", "", "", err
-	}
-	fee, err = l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindCoop, false)))
+	fee, err := l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindCoop)))
 	if err != nil {
 		log.Infof("error getting fee %v", err)
 		fee = feeAmountPlaceholder
@@ -444,7 +408,7 @@ const (
 )
 
 // getEstimatedTxSize estimates the size of a transaction based on its kind and whether it's using Confidential Transactions (CT).
-func getEstimatedTxSize(t transactionKind, ctDiscount bool) int {
+func getEstimatedTxSize(t transactionKind) int {
 	txsize := 0
 	switch t {
 	case transactionKindPreimageSpending:
@@ -463,18 +427,15 @@ func getEstimatedTxSize(t transactionKind, ctDiscount bool) int {
 		// For unknown transaction types, assume a default size of 1360 bytes.
 		return 1360
 	}
-	if ctDiscount {
-		// If CT is enabled, the transaction size is reduced by 75%.
-		// TODO:
-		//   This is a placeholder value, the actual discount should
-		//   be calculated based on discount vsize.
-		//   To do this, we would need to construct the transaction, decode it, and then get the discounted vsize.
-		//   However, this would have a significant impact on the codebase.
-		//   As a temporary measure, we're taking a conservative approach and applying a 75% discount.
-		//   For the discount calculation, refer to https://github.com/ElementsProject/ELIPs/blob/main/elip-0200.mediawiki.
-		return txsize / 4
-	}
-	return txsize
+	// the transaction size is reduced by 75% for ct discount.
+	// TODO:
+	//   This is a placeholder value, the actual discount should
+	//   be calculated based on discount vsize.
+	//   To do this, we would need to construct the transaction, decode it, and then get the discounted vsize.
+	//   However, this would have a significant impact on the codebase.
+	//   As a temporary measure, we're taking a conservative approach and applying a 75% discount.
+	//   For the discount calculation, refer to https://github.com/ElementsProject/ELIPs/blob/main/elip-0200.mediawiki.
+	return txsize / 4
 }
 
 func (l *LiquidOnChain) TxIdFromHex(txHex string) (string, error) {
@@ -620,12 +581,12 @@ func (l *LiquidOnChain) Blech32ToScript(blech32Addr string) ([]byte, error) {
 }
 
 func (l *LiquidOnChain) GetRefundFee() (uint64, error) {
-	return l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindCoop, false)))
+	return l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindCoop)))
 }
 
 // GetFlatOpeningTXFee returns an estimate of the fee for the opening transaction.
 func (l *LiquidOnChain) GetFlatOpeningTXFee() (uint64, error) {
-	return l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindOpening, true)))
+	return l.liquidWallet.GetFee(int64(getEstimatedTxSize(transactionKindOpening)))
 }
 
 func (l *LiquidOnChain) GetAsset() string {