Archives
/
loop
mirror of https://github.com/lightninglabs/loop
2
0
Fork 0
Code Issues Releases Wiki Activity

loopin: store loop in on-chain fees

Browse Source
pull/347/head^2
carla 3 years ago
parent 9ce7fe4df9
commit 4911130671
No known key found for this signature in database
GPG Key ID: 4CA7FE54A6213C91
4 changed files with 109 additions and 25 deletions
Show Stats Download Patch File Download Diff File

64
loopin.go
Unescape Escape View File

@ -12,6 +12,7 @@ import (
"github.com/btcsuite/btcutil"
"github.com/btcsuite/btcd/chaincfg/chainhash"
"github.com/btcsuite/btcd/mempool"
"github.com/btcsuite/btcd/wire"
"github.com/lightninglabs/lndclient"
"github.com/lightninglabs/loop/labels"
@ -21,6 +22,7 @@ import (
"github.com/lightningnetwork/lnd/channeldb"
"github.com/lightningnetwork/lnd/lnrpc/invoicesrpc"
"github.com/lightningnetwork/lnd/lntypes"
"github.com/lightningnetwork/lnd/lnwallet/chainfee"
"github.com/lightningnetwork/lnd/lnwire"
)
@ -311,7 +313,7 @@ func awaitProbe(ctx context.Context, lnd lndclient.LndServices,
// resumeLoopInSwap returns a swap object representing a pending swap that has
// been restored from the database.
func resumeLoopInSwap(reqContext context.Context, cfg *swapConfig,
func resumeLoopInSwap(_ context.Context, cfg *swapConfig,
pend *loopdb.LoopIn) (*loopInSwap, error) {
hash := lntypes.Hash(sha256.Sum256(pend.Contract.Preimage[:]))
@ -339,6 +341,7 @@ func resumeLoopInSwap(reqContext context.Context, cfg *swapConfig,
swap.state = lastUpdate.State
swap.lastUpdateTime = lastUpdate.Time
swap.htlcTxHash = lastUpdate.HtlcTxHash
swap.cost = lastUpdate.Cost
}
return swap, nil
@ -516,8 +519,6 @@ func (s *loopInSwap) executeSwap(globalCtx context.Context) error {
return s.persistAndAnnounceState(globalCtx)
}
// TODO: Add miner fee of htlc tx to swap cost balance.
// The server is expected to see the htlc on-chain and knowing that it
// can sweep that htlc with the preimage, it should pay our swap
// invoice, receive the preimage and sweep the htlc. We are waiting for
@ -662,8 +663,11 @@ func (s *loopInSwap) publishOnChainHtlc(ctx context.Context) (bool, error) {
if err != nil {
return false, fmt.Errorf("send outputs: %v", err)
}
txHash := tx.TxHash()
s.log.Infof("Published on chain HTLC tx %v", txHash)
fee := getTxFee(tx, feeRate.FeePerKVByte())
s.log.Infof("Published on chain HTLC tx %v, fee: %v", txHash, fee)
// Persist the htlc hash so that after a restart we are still waiting
// for our own htlc. We don't need to announce to clients, because the
@ -672,6 +676,12 @@ func (s *loopInSwap) publishOnChainHtlc(ctx context.Context) (bool, error) {
// TODO(joostjager): Store tx hash before calling SendOutputs. This is
// not yet possible with the current lnd api.
s.htlcTxHash = &txHash
// We do not expect any on-chain fees to be recorded yet, and we only
// publish our htlc once, so we set our total on-chain costs to equal
// the fee for publishing the htlc.
s.cost.Onchain = fee
s.lastUpdateTime = time.Now()
if err := s.persistState(); err != nil {
return false, fmt.Errorf("persist htlc tx: %v", err)
@ -681,6 +691,16 @@ func (s *loopInSwap) publishOnChainHtlc(ctx context.Context) (bool, error) {
}
// getTxFee calculates our fee for a transaction that we have broadcast. We use
// sat per kvbyte because this is what lnd uses, and we will run into rounding
// issues if we do not use the same fee rate as lnd.
func getTxFee(tx *wire.MsgTx, fee chainfee.SatPerKVByte) btcutil.Amount {
btcTx := btcutil.NewTx(tx)
vsize := mempool.GetTxVirtualSize(btcTx)
return fee.FeeForVSize(vsize)
}
// waitForSwapComplete waits until a spending tx of the htlc gets confirmed and
// the swap invoice is either settled or canceled. If the htlc times out, the
// timeout tx will be published.
@ -709,17 +729,18 @@ func (s *loopInSwap) waitForSwapComplete(ctx context.Context,
}
// checkTimeout publishes the timeout tx if the contract has expired.
checkTimeout := func() error {
checkTimeout := func() (btcutil.Amount, error) {
if s.height >= s.LoopInContract.CltvExpiry {
return s.publishTimeoutTx(ctx, htlcOutpoint, htlcValue)
}
return nil
return 0, nil
}
// Check timeout at current height. After a restart we may want to
// publish the tx immediately.
err = checkTimeout()
var sweepFee btcutil.Amount
sweepFee, err = checkTimeout()
if err != nil {
return err
}
@ -737,7 +758,7 @@ func (s *loopInSwap) waitForSwapComplete(ctx context.Context,
case notification := <-s.blockEpochChan:
s.height = notification.(int32)
err := checkTimeout()
sweepFee, err = checkTimeout()
if err != nil {
return err
}
@ -749,7 +770,7 @@ func (s *loopInSwap) waitForSwapComplete(ctx context.Context,
spendDetails.SpenderTxHash)
err := s.processHtlcSpend(
ctx, spendDetails, htlcValue,
ctx, spendDetails, htlcValue, sweepFee,
)
if err != nil {
return err
@ -804,7 +825,8 @@ func (s *loopInSwap) waitForSwapComplete(ctx context.Context,
}
func (s *loopInSwap) processHtlcSpend(ctx context.Context,
spend *chainntnfs.SpendDetail, htlcValue btcutil.Amount) error {
spend *chainntnfs.SpendDetail, htlcValue,
sweepFee btcutil.Amount) error {
// Determine the htlc input of the spending tx and inspect the witness
// to findout whether a success or a timeout tx spend the htlc.
@ -817,6 +839,9 @@ func (s *loopInSwap) processHtlcSpend(ctx context.Context,
// server cost balance.
s.cost.Server += htlcValue
} else {
// We needed another on chain tx to sweep the timeout clause,
// which we now include in our costs.
s.cost.Onchain += sweepFee
s.setState(loopdb.StateFailTimeout)
// Now that the timeout tx confirmed, we can safely cancel the
@ -828,23 +853,24 @@ func (s *loopInSwap) processHtlcSpend(ctx context.Context,
if err != nil && err != channeldb.ErrInvoiceAlreadySettled {
return err
}
// TODO: Add miner fee of timeout tx to swap cost balance.
}
return nil
}
// publishTimeoutTx publishes a timeout tx after the on-chain htlc has expired.
// The swap failed and we are reclaiming our funds.
// publishTimeoutTx publishes a timeout tx after the on-chain htlc has expired,
// returning the fee that is paid by the sweep tx. We cannot update our swap
// costs in this function because it is called multiple times. The swap failed
// and we are reclaiming our funds.
func (s *loopInSwap) publishTimeoutTx(ctx context.Context,
htlcOutpoint *wire.OutPoint, htlcValue btcutil.Amount) error {
htlcOutpoint *wire.OutPoint, htlcValue btcutil.Amount) (btcutil.Amount,
error) {
if s.timeoutAddr == nil {
var err error
s.timeoutAddr, err = s.lnd.WalletKit.NextAddr(ctx)
if err != nil {
return err
return 0, err
}
}
@ -854,7 +880,7 @@ func (s *loopInSwap) publishTimeoutTx(ctx context.Context,
TimeoutTxConfTarget,
)
if err != nil {
return err
return 0, err
}
witnessFunc := func(sig []byte) (wire.TxWitness, error) {
@ -867,7 +893,7 @@ func (s *loopInSwap) publishTimeoutTx(ctx context.Context,
witnessFunc, htlcValue, fee, s.timeoutAddr,
)
if err != nil {
return err
return 0, err
}
timeoutTxHash := timeoutTx.TxHash()
@ -882,7 +908,7 @@ func (s *loopInSwap) publishTimeoutTx(ctx context.Context,
s.log.Warnf("publish timeout: %v", err)
}
return nil
return fee, nil
}
// persistAndAnnounceState updates the swap state on disk and sends out an

62
loopin_test.go
Unescape Escape View File

@ -64,9 +64,17 @@ func TestLoopInSuccess(t *testing.T) {
// Expect htlc to be published.
htlcTx := <-ctx.lnd.SendOutputsChannel
// Expect the same state to be written again with the htlc tx hash.
// We expect our cost to use the mock fee rate we set for our conf
// target.
cost := loopdb.SwapCost{
Onchain: getTxFee(&htlcTx, test.DefaultMockFee.FeePerKVByte()),
}
// Expect the same state to be written again with the htlc tx hash
// and on chain fee.
state := ctx.store.assertLoopInState(loopdb.StateHtlcPublished)
require.NotNil(t, state.HtlcTxHash)
require.Equal(t, cost, state.Cost)
// Expect register for htlc conf.
<-ctx.lnd.RegisterConfChannel
@ -186,14 +194,24 @@ func testLoopInTimeout(t *testing.T,
ctx.assertState(loopdb.StateHtlcPublished)
ctx.store.assertLoopInState(loopdb.StateHtlcPublished)
var htlcTx wire.MsgTx
var (
htlcTx wire.MsgTx
cost loopdb.SwapCost
)
if externalValue == 0 {
// Expect htlc to be published.
htlcTx = <-ctx.lnd.SendOutputsChannel
cost = loopdb.SwapCost{
Onchain: getTxFee(
&htlcTx, test.DefaultMockFee.FeePerKVByte(),
),
}
// Expect the same state to be written again with the htlc tx hash.
// Expect the same state to be written again with the htlc tx
// hash and cost.
state := ctx.store.assertLoopInState(loopdb.StateHtlcPublished)
require.NotNil(t, state.HtlcTxHash)
require.Equal(t, cost, state.Cost)
} else {
// Create an external htlc publish tx.
var pkScript []byte
@ -257,6 +275,15 @@ func testLoopInTimeout(t *testing.T,
// Expect timeout tx to be published.
timeoutTx := <-ctx.lnd.TxPublishChannel
// We can just get our sweep fee as we would in the swap code because
// our estimate is static.
fee, err := s.sweeper.GetSweepFee(
context.Background(), s.htlc.AddTimeoutToEstimator,
s.timeoutAddr, TimeoutTxConfTarget,
)
require.NoError(t, err)
cost.Onchain += fee
// Confirm timeout tx.
ctx.lnd.SpendChannel <- &chainntnfs.SpendDetail{
SpendingTx: timeoutTx,
@ -273,7 +300,8 @@ func testLoopInTimeout(t *testing.T,
}
ctx.assertState(loopdb.StateFailTimeout)
ctx.store.assertLoopInState(loopdb.StateFailTimeout)
state := ctx.store.assertLoopInState(loopdb.StateFailTimeout)
require.Equal(t, cost, state.Cost)
err = <-errChan
if err != nil {
@ -360,6 +388,16 @@ func testLoopInResume(t *testing.T, state loopdb.SwapState, expired bool,
},
}
// If we have already published the htlc, we expect our cost to already
// be published.
var cost loopdb.SwapCost
if state == loopdb.StateHtlcPublished {
cost = loopdb.SwapCost{
Onchain: 999,
}
pendSwap.Loop.Events[0].Cost = cost
}
htlc, err := swap.NewHtlc(
scriptVersion, contract.CltvExpiry, contract.SenderKey,
contract.ReceiverKey, testPreimage.Hash(), swap.HtlcNP2WSH,
@ -431,6 +469,11 @@ func testLoopInResume(t *testing.T, state loopdb.SwapState, expired bool,
// Expect htlc to be published.
htlcTx = <-ctx.lnd.SendOutputsChannel
cost = loopdb.SwapCost{
Onchain: getTxFee(
&htlcTx, test.DefaultMockFee.FeePerKVByte(),
),
}
// Expect the same state to be written again with the htlc tx
// hash.
@ -465,10 +508,11 @@ func testLoopInResume(t *testing.T, state loopdb.SwapState, expired bool,
// Server has already paid invoice before spending the htlc. Signal
// settled.
subscription.Update <- lndclient.InvoiceUpdate{
invoiceUpdate := lndclient.InvoiceUpdate{
State: channeldb.ContractSettled,
AmtPaid: 49000,
}
subscription.Update <- invoiceUpdate
// Swap is expected to move to the state InvoiceSettled
ctx.assertState(loopdb.StateInvoiceSettled)
@ -488,4 +532,12 @@ func testLoopInResume(t *testing.T, state loopdb.SwapState, expired bool,
}
ctx.assertState(loopdb.StateSuccess)
finalState := ctx.store.assertLoopInState(loopdb.StateSuccess)
// We expect our server fee to reflect as the difference between htlc
// value and invoice amount paid. We use our original on-chain cost, set
// earlier in the test, because we expect this value to be unchanged.
cost.Server = btcutil.Amount(htlcTx.TxOut[0].Value) -
invoiceUpdate.AmtPaid
require.Equal(t, cost, finalState.Cost)
}

2
release_notes.md
Unescape Escape View File

@ -24,3 +24,5 @@ This file tracks release notes for the loop client.
#### Breaking Changes
#### Bug Fixes
* A bug where loop in on-chain fees were not recorded properly has been
addressed.

6
test/walletkit_mock.go
Unescape Escape View File

@ -16,6 +16,10 @@ import (
"github.com/lightningnetwork/lnd/lnwallet/chainfee"
)
// DefaultMockFee is the default value we use for fee estimates when no values
// are set for specific conf targets.
var DefaultMockFee = chainfee.SatPerKWeight(10000)
type mockWalletKit struct {
lnd *LndMockServices
keyIndex int32
@ -123,7 +127,7 @@ func (m *mockWalletKit) EstimateFee(ctx context.Context, confTarget int32) (
feeEstimate, ok := m.feeEstimates[confTarget]
if !ok {
return 10000, nil
return DefaultMockFee, nil
}
return feeEstimate, nil

Write Preview
Loading…
Cancel
Save