lnd.xprv/sweep/walletsweep.go
Olaoluwa Osuntokun 73c9c2ee15
sweep+cnct+nursery+rpc: extract DetermineFeePerKw to func, add FeePreference
In this commit, we extract the existing determineFeePerKw method on the
RPC server into a new file in the sweep package. Along the way, we
consolidate code by introducing a new FeePreference struct, which allows
the caller to express their fee preference either in blocks to
confirmation, or a direct fee rate. This move takes a small step to
father decoupling calls in the main RPC server.
2019-01-09 15:55:17 -08:00

69 lines
2.0 KiB
Go

package sweep
import (
"fmt"
"github.com/lightningnetwork/lnd/lnwallet"
)
// FeePreference allows callers to express their time value for inclusion of a
// transaction into a block via either a confirmation target, or a fee rate.
type FeePreference struct {
// ConfTarget if non-zero, signals a fee preference expressed in the
// number of desired blocks between first broadcast, and confirmation.
ConfTarget uint32
// FeeRate if non-zero, signals a fee pre fence expressed in the fee
// rate expressed in sat/kw for a particular transaction.
FeeRate lnwallet.SatPerKWeight
}
// DetermineFeePerKw will determine the fee in sat/kw that should be paid given
// an estimator, a confirmation target, and a manual value for sat/byte. A
// value is chosen based on the two free parameters as one, or both of them can
// be zero.
func DetermineFeePerKw(feeEstimator lnwallet.FeeEstimator,
feePref FeePreference) (lnwallet.SatPerKWeight, error) {
switch {
// If the target number of confirmations is set, then we'll use that to
// consult our fee estimator for an adequate fee.
case feePref.ConfTarget != 0:
feePerKw, err := feeEstimator.EstimateFeePerKW(
uint32(feePref.ConfTarget),
)
if err != nil {
return 0, fmt.Errorf("unable to query fee "+
"estimator: %v", err)
}
return feePerKw, nil
// If a manual sat/byte fee rate is set, then we'll use that directly.
// We'll need to convert it to sat/kw as this is what we use
// internally.
case feePref.FeeRate != 0:
feePerKW := feePref.FeeRate
if feePerKW < lnwallet.FeePerKwFloor {
log.Infof("Manual fee rate input of %d sat/kw is "+
"too low, using %d sat/kw instead", feePerKW,
lnwallet.FeePerKwFloor)
feePerKW = lnwallet.FeePerKwFloor
}
return feePerKW, nil
// Otherwise, we'll attempt a relaxed confirmation target for the
// transaction
default:
feePerKw, err := feeEstimator.EstimateFeePerKW(6)
if err != nil {
return 0, fmt.Errorf("unable to query fee estimator: "+
"%v", err)
}
return feePerKw, nil
}
}