@ -1,4 +1,4 @@
package lnwallet
package chainfee
import (
"encoding/json"
@ -10,85 +10,41 @@ import (
"sync"
"time"
"github.com/btcsuite/btcd/blockchain"
"github.com/btcsuite/btcd/rpcclient"
"github.com/btcsuite/btcutil"
)
const (
// FeePerKwFloor is the lowest fee rate in sat/kw that we should use for
// determining transaction fees.
FeePerKwFloor SatPerKWeight = 253
// maxBlockTarget is the highest number of blocks confirmations that
// a WebAPIFee Estimator will cache fees for. This number is chosen
// a WebAPIEstimator will cache fees for. This number is chosen
// because it's the highest number of confs bitcoind will return a fee
// estimate for.
maxBlockTarget uint32 = 1009
// minBlockTarget is the lowest number of blocks confirmations that
// a WebAPIFee Estimator will cache fees for. Requesting an estimate for
// a WebAPIEstimator will cache fees for. Requesting an estimate for
// less than this will result in an error.
minBlockTarget uint32 = 2
// minFeeUpdateTimeout represents the minimum interval in which a
// WebAPIFee Estimator will request fresh fees from its API.
// WebAPIEstimator will request fresh fees from its API.
minFeeUpdateTimeout = 5 * time . Minute
// maxFeeUpdateTimeout represents the maximum interval in which a
// WebAPIFee Estimator will request fresh fees from its API.
// WebAPIEstimator will request fresh fees from its API.
maxFeeUpdateTimeout = 20 * time . Minute
)
// SatPerKVByte represents a fee rate in sat/kb.
type SatPerKVByte btcutil . Amount
// FeeForVSize calculates the fee resulting from this fee rate and the given
// vsize in vbytes.
func ( s SatPerKVByte ) FeeForVSize ( vbytes int64 ) btcutil . Amount {
return btcutil . Amount ( s ) * btcutil . Amount ( vbytes ) / 1000
}
// FeePerKWeight converts the current fee rate from sat/kb to sat/kw.
func ( s SatPerKVByte ) FeePerKWeight ( ) SatPerKWeight {
return SatPerKWeight ( s / blockchain . WitnessScaleFactor )
}
// String returns a human-readable string of the fee rate.
func ( s SatPerKVByte ) String ( ) string {
return fmt . Sprintf ( "%v sat/kb" , int64 ( s ) )
}
// SatPerKWeight represents a fee rate in sat/kw.
type SatPerKWeight btcutil . Amount
// FeeForWeight calculates the fee resulting from this fee rate and the given
// weight in weight units (wu).
func ( s SatPerKWeight ) FeeForWeight ( wu int64 ) btcutil . Amount {
// The resulting fee is rounded down, as specified in BOLT#03.
return btcutil . Amount ( s ) * btcutil . Amount ( wu ) / 1000
}
// FeePerKVByte converts the current fee rate from sat/kw to sat/kb.
func ( s SatPerKWeight ) FeePerKVByte ( ) SatPerKVByte {
return SatPerKVByte ( s * blockchain . WitnessScaleFactor )
}
// String returns a human-readable string of the fee rate.
func ( s SatPerKWeight ) String ( ) string {
return fmt . Sprintf ( "%v sat/kw" , int64 ( s ) )
}
// FeeEstimator provides the ability to estimate on-chain transaction fees for
// Estimator provides the ability to estimate on-chain transaction fees for
// various combinations of transaction sizes and desired confirmation time
// (measured by number of blocks).
type Fee Estimatorinterface {
type Estimator interface {
// EstimateFeePerKW takes in a target for the number of blocks until an
// initial confirmation and returns the estimated fee expressed in
// sat/kw.
EstimateFeePerKW ( numBlocks uint32 ) ( SatPerKWeight , error )
// Start signals the Fee Estimator to start any processes or goroutines
// Start signals the Estimator to start any processes or goroutines
// it needs to perform its duty.
Start ( ) error
@ -102,11 +58,11 @@ type FeeEstimator interface {
RelayFeePerKW ( ) SatPerKWeight
}
// StaticFee Estimator will return a static value for all fee calculation
// requests. It is designed to be replaced by a proper fee calculation
// implementation. The fees are not accessible directly, because changing them
// would not be thread safe.
type StaticFee Estimator struct {
// StaticEstimator will return a static value for all fee calculation requests.
// It is designed to be replaced by a proper fee calculation implementation.
// The fees are not accessible directly, because changing them would not be
// thread safe.
type StaticEstimator struct {
// feePerKW is the static fee rate in satoshis-per-vbyte that will be
// returned by this fee estimator.
feePerKW SatPerKWeight
@ -116,11 +72,10 @@ type StaticFeeEstimator struct {
relayFee SatPerKWeight
}
// NewStaticFeeEstimator returns a new static fee estimator instance.
func NewStaticFeeEstimator ( feePerKW ,
relayFee SatPerKWeight ) * StaticFeeEstimator {
// NewStaticEstimator returns a new static fee estimator instance.
func NewStaticEstimator ( feePerKW , relayFee SatPerKWeight ) * StaticEstimator {
return & StaticFee Estimator {
return & StaticEstimator {
feePerKW : feePerKW ,
relayFee : relayFee ,
}
@ -128,43 +83,43 @@ func NewStaticFeeEstimator(feePerKW,
// EstimateFeePerKW will return a static value for fee calculations.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( e StaticFee Estimator ) EstimateFeePerKW ( numBlocks uint32 ) ( SatPerKWeight , error ) {
// NOTE: This method is part of the Estimator interface.
func ( e StaticEstimator ) EstimateFeePerKW ( numBlocks uint32 ) ( SatPerKWeight , error ) {
return e . feePerKW , nil
}
// RelayFeePerKW returns the minimum fee rate required for transactions to be
// relayed.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( e StaticFee Estimator ) RelayFeePerKW ( ) SatPerKWeight {
// NOTE: This method is part of the Estimator interface.
func ( e StaticEstimator ) RelayFeePerKW ( ) SatPerKWeight {
return e . relayFee
}
// Start signals the Fee Estimator to start any processes or goroutines
// Start signals the Estimator to start any processes or goroutines
// it needs to perform its duty.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( e StaticFee Estimator ) Start ( ) error {
// NOTE: This method is part of the Estimator interface.
func ( e StaticEstimator ) Start ( ) error {
return nil
}
// Stop stops any spawned goroutines and cleans up the resources used
// by the fee estimator.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( e StaticFee Estimator ) Stop ( ) error {
// NOTE: This method is part of the Estimator interface.
func ( e StaticEstimator ) Stop ( ) error {
return nil
}
// A compile-time assertion to ensure that StaticFeeEstimator implements the
// Fee Estimator interface.
var _ Fee Estimator= ( * StaticFee Estimator ) ( nil )
// Estimator interface.
var _ Estimator = ( * StaticEstimator ) ( nil )
// BtcdFee Estimator is an implementation of the Fee Estimator interface backed
// BtcdEstimator is an implementation of the Estimator interface backed
// by the RPC interface of an active btcd node. This implementation will proxy
// any fee estimation requests to btcd's RPC interface.
type BtcdFee Estimator struct {
type BtcdEstimator struct {
// fallbackFeePerKW is the fall back fee rate in sat/kw that is returned
// if the fee estimator does not yet have enough data to actually
// produce fee estimates.
@ -179,13 +134,13 @@ type BtcdFeeEstimator struct {
btcdConn * rpcclient . Client
}
// NewBtcdFee Estimator creates a new BtcdFee Estimator given a fully populated
// NewBtcdEstimator creates a new BtcdEstimator given a fully populated
// rpc config that is able to successfully connect and authenticate with the
// btcd node, and also a fall back fee rate. The fallback fee rate is used in
// the occasion that the estimator has insufficient data, or returns zero for a
// fee estimate.
func NewBtcdFee Estimator ( rpcConfig rpcclient . ConnConfig ,
fallBackFeeRate SatPerKWeight ) ( * BtcdFee Estimator , error ) {
func NewBtcdEstimator ( rpcConfig rpcclient . ConnConfig ,
fallBackFeeRate SatPerKWeight ) ( * BtcdEstimator , error ) {
rpcConfig . DisableConnectOnNew = true
rpcConfig . DisableAutoReconnect = false
@ -194,17 +149,17 @@ func NewBtcdFeeEstimator(rpcConfig rpcclient.ConnConfig,
return nil , err
}
return & BtcdFee Estimator {
return & BtcdEstimator {
fallbackFeePerKW : fallBackFeeRate ,
btcdConn : chainConn ,
} , nil
}
// Start signals the Fee Estimator to start any processes or goroutines
// Start signals the Estimator to start any processes or goroutines
// it needs to perform its duty.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( b * BtcdFee Estimator ) Start ( ) error {
// NOTE: This method is part of the Estimator interface.
func ( b * BtcdEstimator ) Start ( ) error {
if err := b . btcdConn . Connect ( 20 ) ; err != nil {
return err
}
@ -233,7 +188,7 @@ func (b *BtcdFeeEstimator) Start() error {
b . minFeePerKW = FeePerKwFloor
}
wa lletL og. Debugf ( "Using minimum fee rate of %v sat/kw" ,
log . Debugf ( "Using minimum fee rate of %v sat/kw" ,
int64 ( b . minFeePerKW ) )
return nil
@ -242,8 +197,8 @@ func (b *BtcdFeeEstimator) Start() error {
// Stop stops any spawned goroutines and cleans up the resources used
// by the fee estimator.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( b * BtcdFee Estimator ) Stop ( ) error {
// NOTE: This method is part of the Estimator interface.
func ( b * BtcdEstimator ) Stop ( ) error {
b . btcdConn . Shutdown ( )
return nil
@ -252,15 +207,15 @@ func (b *BtcdFeeEstimator) Stop() error {
// EstimateFeePerKW takes in a target for the number of blocks until an initial
// confirmation and returns the estimated fee expressed in sat/kw.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( b * BtcdFee Estimator ) EstimateFeePerKW ( numBlocks uint32 ) ( SatPerKWeight , error ) {
// NOTE: This method is part of the Estimator interface.
func ( b * BtcdEstimator ) EstimateFeePerKW ( numBlocks uint32 ) ( SatPerKWeight , error ) {
feeEstimate , err := b . fetchEstimate ( numBlocks )
switch {
// If the estimator doesn't have enough data, or returns an error, then
// to return a proper value, then we'll return the default fall back
// fee rate.
case err != nil :
wa lletL og. Errorf ( "unable to query estimator: %v" , err )
log . Errorf ( "unable to query estimator: %v" , err )
fallthrough
case feeEstimate == 0 :
@ -273,14 +228,14 @@ func (b *BtcdFeeEstimator) EstimateFeePerKW(numBlocks uint32) (SatPerKWeight, er
// RelayFeePerKW returns the minimum fee rate required for transactions to be
// relayed.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( b * BtcdFee Estimator ) RelayFeePerKW ( ) SatPerKWeight {
// NOTE: This method is part of the Estimator interface.
func ( b * BtcdEstimator ) RelayFeePerKW ( ) SatPerKWeight {
return b . minFeePerKW
}
// fetchEstimate returns a fee estimate for a transaction to be confirmed in
// confTarget blocks. The estimate is returned in sat/kw.
func ( b * BtcdFee Estimator ) fetchEstimate ( confTarget uint32 ) ( SatPerKWeight , error ) {
func ( b * BtcdEstimator ) fetchEstimate ( confTarget uint32 ) ( SatPerKWeight , error ) {
// First, we'll fetch the estimate for our confirmation target.
btcPerKB , err := b . btcdConn . EstimateFee ( int64 ( confTarget ) )
if err != nil {
@ -300,26 +255,26 @@ func (b *BtcdFeeEstimator) fetchEstimate(confTarget uint32) (SatPerKWeight, erro
// Finally, we'll enforce our fee floor.
if satPerKw < b . minFeePerKW {
wa lletL og. Debugf ( "Estimated fee rate of %v sat/kw is too low, " +
log . Debugf ( "Estimated fee rate of %v sat/kw is too low, " +
"using fee floor of %v sat/kw instead" , satPerKw ,
b . minFeePerKW )
satPerKw = b . minFeePerKW
}
wa lletL og. Debugf ( "Returning %v sat/kw for conf target of %v" ,
log . Debugf ( "Returning %v sat/kw for conf target of %v" ,
int64 ( satPerKw ) , confTarget )
return satPerKw , nil
}
// A compile-time assertion to ensure that BtcdFee Estimator implements the
// Fee Estimator interface.
var _ Fee Estimator= ( * BtcdFee Estimator ) ( nil )
// A compile-time assertion to ensure that BtcdEstimator implements the
// Estimator interface.
var _ Estimator = ( * BtcdEstimator ) ( nil )
// BitcoindFee Estimator is an implementation of the Fee Estimator interface
// backed by the RPC interface of an active bitcoind node. This implementation
// will proxy any fee estimation requests to bitcoind's RPC interface.
type BitcoindFee Estimator struct {
// BitcoindEstimator is an implementation of the Estimator interface backed by
// the RPC interface of an active bitcoind node. This implementation will proxy
// any fee estimation requests to bitcoind's RPC interface.
type BitcoindEstimator struct {
// fallbackFeePerKW is the fallback fee rate in sat/kw that is returned
// if the fee estimator does not yet have enough data to actually
// produce fee estimates.
@ -334,13 +289,13 @@ type BitcoindFeeEstimator struct {
bitcoindConn * rpcclient . Client
}
// NewBitcoindFee Estimator creates a new BitcoindFee Estimator given a fully
// populated rpc config that is able to successfully connect and authenticate
// with the bitcoind node, and also a fall back fee rate. The fallback fee rate
// is used i n the occasion that the estimator has insufficient data, or returns
// zero for a fee estimate.
func NewBitcoindFee Estimator ( rpcConfig rpcclient . ConnConfig ,
fallBackFeeRate SatPerKWeight ) ( * BitcoindFee Estimator , error ) {
// NewBitcoindEstimator creates a new BitcoindEstimator given a fully populated
// rpc config that is able to successfully connect and authenticate with th e
// bitcoind node, and also a fall back fee rate. The fallback fee rate is used
// in the occasion that the estimator has insufficient data, or returns zero
// for a fee estimate.
func NewBitcoindEstimator ( rpcConfig rpcclient . ConnConfig ,
fallBackFeeRate SatPerKWeight ) ( * BitcoindEstimator , error ) {
rpcConfig . DisableConnectOnNew = true
rpcConfig . DisableAutoReconnect = false
@ -351,17 +306,17 @@ func NewBitcoindFeeEstimator(rpcConfig rpcclient.ConnConfig,
return nil , err
}
return & BitcoindFee Estimator {
return & BitcoindEstimator {
fallbackFeePerKW : fallBackFeeRate ,
bitcoindConn : chainConn ,
} , nil
}
// Start signals the Fee Estimator to start any processes or goroutines
// Start signals the Estimator to start any processes or goroutines
// it needs to perform its duty.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( b * BitcoindFee Estimator ) Start ( ) error {
// NOTE: This method is part of the Estimator interface.
func ( b * BitcoindEstimator ) Start ( ) error {
// Once the connection to the backend node has been established, we'll
// query it for its minimum relay fee. Since the `getinfo` RPC has been
// deprecated for `bitcoind`, we'll need to send a `getnetworkinfo`
@ -396,7 +351,7 @@ func (b *BitcoindFeeEstimator) Start() error {
b . minFeePerKW = FeePerKwFloor
}
wa lletL og. Debugf ( "Using minimum fee rate of %v sat/kw" ,
log . Debugf ( "Using minimum fee rate of %v sat/kw" ,
int64 ( b . minFeePerKW ) )
return nil
@ -405,23 +360,23 @@ func (b *BitcoindFeeEstimator) Start() error {
// Stop stops any spawned goroutines and cleans up the resources used
// by the fee estimator.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( b * BitcoindFee Estimator ) Stop ( ) error {
// NOTE: This method is part of the Estimator interface.
func ( b * BitcoindEstimator ) Stop ( ) error {
return nil
}
// EstimateFeePerKW takes in a target for the number of blocks until an initial
// confirmation and returns the estimated fee expressed in sat/kw.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( b * BitcoindFee Estimator ) EstimateFeePerKW ( numBlocks uint32 ) ( SatPerKWeight , error ) {
// NOTE: This method is part of the Estimator interface.
func ( b * BitcoindEstimator ) EstimateFeePerKW ( numBlocks uint32 ) ( SatPerKWeight , error ) {
feeEstimate , err := b . fetchEstimate ( numBlocks )
switch {
// If the estimator doesn't have enough data, or returns an error, then
// to return a proper value, then we'll return the default fall back
// fee rate.
case err != nil :
wa lletL og. Errorf ( "unable to query estimator: %v" , err )
log . Errorf ( "unable to query estimator: %v" , err )
fallthrough
case feeEstimate == 0 :
@ -434,14 +389,14 @@ func (b *BitcoindFeeEstimator) EstimateFeePerKW(numBlocks uint32) (SatPerKWeight
// RelayFeePerKW returns the minimum fee rate required for transactions to be
// relayed.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( b * BitcoindFee Estimator ) RelayFeePerKW ( ) SatPerKWeight {
// NOTE: This method is part of the Estimator interface.
func ( b * BitcoindEstimator ) RelayFeePerKW ( ) SatPerKWeight {
return b . minFeePerKW
}
// fetchEstimate returns a fee estimate for a transaction to be confirmed in
// confTarget blocks. The estimate is returned in sat/kw.
func ( b * BitcoindFee Estimator ) fetchEstimate ( confTarget uint32 ) ( SatPerKWeight , error ) {
func ( b * BitcoindEstimator ) fetchEstimate ( confTarget uint32 ) ( SatPerKWeight , error ) {
// First, we'll send an "estimatesmartfee" command as a raw request,
// since it isn't supported by btcd but is available in bitcoind.
target , err := json . Marshal ( uint64 ( confTarget ) )
@ -478,26 +433,26 @@ func (b *BitcoindFeeEstimator) fetchEstimate(confTarget uint32) (SatPerKWeight,
// Finally, we'll enforce our fee floor.
if satPerKw < b . minFeePerKW {
wa lletL og. Debugf ( "Estimated fee rate of %v sat/kw is too low, " +
log . Debugf ( "Estimated fee rate of %v sat/kw is too low, " +
"using fee floor of %v sat/kw instead" , satPerKw ,
b . minFeePerKW )
satPerKw = b . minFeePerKW
}
wa lletL og. Debugf ( "Returning %v sat/kw for conf target of %v" ,
log . Debugf ( "Returning %v sat/kw for conf target of %v" ,
int64 ( satPerKw ) , confTarget )
return satPerKw , nil
}
// A compile-time assertion to ensure that BitcoindFee Estimator implements the
// Fee Estimator interface.
var _ Fee Estimator= ( * BitcoindFee Estimator ) ( nil )
// A compile-time assertion to ensure that BitcoindEstimator implements the
// Estimator interface.
var _ Estimator = ( * BitcoindEstimator ) ( nil )
// WebAPIFeeSource is an interface allows the WebAPIFee Estimator to query an
// WebAPIFeeSource is an interface allows the WebAPIEstimator to query an
// arbitrary HTTP-based fee estimator. Each new set/network will gain an
// implementation of this interface in order to allow the WebAPIFee Estimator to
// implementation of this interface in order to allow the WebAPIEstimator to
// be fully generic in its logic.
type WebAPIFeeSource interface {
// GenQueryURL generates the full query URL. The value returned by this
@ -554,9 +509,9 @@ func (s SparseConfFeeSource) ParseResponse(r io.Reader) (map[uint32]uint32, erro
// WebAPIFeeSource interface.
var _ WebAPIFeeSource = ( * SparseConfFeeSource ) ( nil )
// WebAPIFee Estimator is an implementation of the Fee Estimator interface that
// WebAPIEstimator is an implementation of the Estimator interface that
// queries an HTTP-based fee estimation from an existing web API.
type WebAPIFee Estimator struct {
type WebAPIEstimator struct {
started sync . Once
stopped sync . Once
@ -581,12 +536,12 @@ type WebAPIFeeEstimator struct {
wg sync . WaitGroup
}
// NewWebAPIFee Estimator creates a new WebAPIFee Estimator from a given URL and a
// NewWebAPIEstimator creates a new WebAPIEstimator from a given URL and a
// fallback default fee. The fees are updated whenever a new block is mined.
func NewWebAPIFee Estimator (
api WebAPIFeeSource , defaultFee SatPerKWeight ) * WebAPIFee Estimator {
func NewWebAPIEstimator (
api WebAPIFeeSource , defaultFee SatPerKWeight ) * WebAPIEstimator {
return & WebAPIFee Estimator {
return & WebAPIEstimator {
apiSource : api ,
feeByBlockTarget : make ( map [ uint32 ] uint32 ) ,
defaultFeePerKw : defaultFee ,
@ -597,8 +552,8 @@ func NewWebAPIFeeEstimator(
// EstimateFeePerKW takes in a target for the number of blocks until an initial
// confirmation and returns the estimated fee expressed in sat/kw.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( w * WebAPIFee Estimator ) EstimateFeePerKW ( numBlocks uint32 ) ( SatPerKWeight , error ) {
// NOTE: This method is part of the Estimator interface.
func ( w * WebAPIEstimator ) EstimateFeePerKW ( numBlocks uint32 ) ( SatPerKWeight , error ) {
if numBlocks > maxBlockTarget {
numBlocks = maxBlockTarget
} else if numBlocks < minBlockTarget {
@ -618,20 +573,20 @@ func (w *WebAPIFeeEstimator) EstimateFeePerKW(numBlocks uint32) (SatPerKWeight,
satPerKw = FeePerKwFloor
}
wa lletL og. Debugf ( "Web API returning %v sat/kw for conf target of %v" ,
log . Debugf ( "Web API returning %v sat/kw for conf target of %v" ,
int64 ( satPerKw ) , numBlocks )
return satPerKw , nil
}
// Start signals the Fee Estimator to start any processes or goroutines it needs
// Start signals the Estimator to start any processes or goroutines it needs
// to perform its duty.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( w * WebAPIFee Estimator ) Start ( ) error {
// NOTE: This method is part of the Estimator interface.
func ( w * WebAPIEstimator ) Start ( ) error {
var err error
w . started . Do ( func ( ) {
wa lletL og. Infof ( "Starting web API fee estimator" )
log . Infof ( "Starting web API fee estimator" )
w . updateFeeTicker = time . NewTicker ( w . randomFeeUpdateTimeout ( ) )
w . updateFeeEstimates ( )
@ -646,10 +601,10 @@ func (w *WebAPIFeeEstimator) Start() error {
// Stop stops any spawned goroutines and cleans up the resources used by the
// fee estimator.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( w * WebAPIFee Estimator ) Stop ( ) error {
// NOTE: This method is part of the Estimator interface.
func ( w * WebAPIEstimator ) Stop ( ) error {
w . stopped . Do ( func ( ) {
wa lletL og. Infof ( "Stopping web API fee estimator" )
log . Infof ( "Stopping web API fee estimator" )
w . updateFeeTicker . Stop ( )
@ -662,15 +617,15 @@ func (w *WebAPIFeeEstimator) Stop() error {
// RelayFeePerKW returns the minimum fee rate required for transactions to be
// relayed.
//
// NOTE: This method is part of the Fee Estimator interface.
func ( w * WebAPIFee Estimator ) RelayFeePerKW ( ) SatPerKWeight {
// NOTE: This method is part of the Estimator interface.
func ( w * WebAPIEstimator ) RelayFeePerKW ( ) SatPerKWeight {
return FeePerKwFloor
}
// randomFeeUpdateTimeout returns a random timeout between minFeeUpdateTimeout
// and maxFeeUpdateTimeout that will be used to determine how often the Estimator
// should retrieve fresh fees from its API.
func ( w * WebAPIFee Estimator ) randomFeeUpdateTimeout ( ) time . Duration {
func ( w * WebAPIEstimator ) randomFeeUpdateTimeout ( ) time . Duration {
lower := int64 ( minFeeUpdateTimeout )
upper := int64 ( maxFeeUpdateTimeout )
return time . Duration ( prand . Int63n ( upper - lower ) + lower )
@ -679,7 +634,7 @@ func (w *WebAPIFeeEstimator) randomFeeUpdateTimeout() time.Duration {
// getCachedFee takes in a target for the number of blocks until an initial
// confirmation and returns an estimated fee (if one was returned by the API). If
// the fee was not previously cached, we cache it here.
func ( w * WebAPIFee Estimator ) getCachedFee ( numBlocks uint32 ) ( uint32 , error ) {
func ( w * WebAPIEstimator ) getCachedFee ( numBlocks uint32 ) ( uint32 , error ) {
w . feesMtx . Lock ( )
defer w . feesMtx . Unlock ( )
@ -704,7 +659,7 @@ func (w *WebAPIFeeEstimator) getCachedFee(numBlocks uint32) (uint32, error) {
}
// updateFeeEstimates re-queries the API for fresh fees and caches them.
func ( w * WebAPIFee Estimator ) updateFeeEstimates ( ) {
func ( w * WebAPIEstimator ) updateFeeEstimates ( ) {
// Rather than use the default http.Client, we'll make a custom one
// which will allow us to control how long we'll wait to read the
// response from the service. This way, if the service is down or
@ -725,7 +680,7 @@ func (w *WebAPIFeeEstimator) updateFeeEstimates() {
targetURL := w . apiSource . GenQueryURL ( )
resp , err := netClient . Get ( targetURL )
if err != nil {
wa lletL og. Errorf ( "unable to query web api for fee response: %v" ,
log . Errorf ( "unable to query web api for fee response: %v" ,
err )
return
}
@ -735,7 +690,7 @@ func (w *WebAPIFeeEstimator) updateFeeEstimates() {
// to parse out the body to obtain our final result.
feesByBlockTarget , err := w . apiSource . ParseResponse ( resp . Body )
if err != nil {
wa lletL og. Errorf ( "unable to query web api for fee response: %v" ,
log . Errorf ( "unable to query web api for fee response: %v" ,
err )
return
}
@ -746,7 +701,7 @@ func (w *WebAPIFeeEstimator) updateFeeEstimates() {
}
// feeUpdateManager updates the fee estimates whenever a new block comes in.
func ( w * WebAPIFee Estimator ) feeUpdateManager ( ) {
func ( w * WebAPIEstimator ) feeUpdateManager ( ) {
defer w . wg . Done ( )
for {
@ -759,6 +714,6 @@ func (w *WebAPIFeeEstimator) feeUpdateManager() {
}
}
// A compile-time assertion to ensure that WebAPIFee Estimator implements the
// Fee Estimator interface.
var _ Fee Estimator= ( * WebAPIFee Estimator ) ( nil )
// A compile-time assertion to ensure that WebAPIEstimator implements the
// Estimator interface.
var _ Estimator = ( * WebAPIEstimator ) ( nil )
Olaoluwa Osuntokun
5 years ago