config: allow web fee estimation on regtest

chainregistry.go

@@ -2,6 +2,7 @@ package lnd
 
 import (
 	"encoding/hex"
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"net"
@@ -249,16 +250,15 @@ func newChainControlFromConfig(cfg *Config, localDB, remoteDB *channeldb.DB,
 			return nil, err
 		}
 
-		// If the user provided an API for fee estimation, activate it now.
+		// Map the deprecated neutrino feeurl flag to the general fee
+		// url.
 		if cfg.NeutrinoMode.FeeURL != "" {
-			ltndLog.Infof("Using API fee estimator!")
+			if cfg.FeeURL != "" {
+				return nil, errors.New("feeurl and " +
+					"neutrino.feeurl are mutually exclusive")
+			}
 
-			cc.feeEstimator = chainfee.NewWebAPIEstimator(
-				chainfee.SparseConfFeeSource{
-					URL: cfg.NeutrinoMode.FeeURL,
-				},
-				false,
-			)
+			cfg.FeeURL = cfg.NeutrinoMode.FeeURL
 		}
 
 		walletConfig.ChainSource = chain.NewNeutrinoClient(
@@ -485,6 +485,23 @@ func newChainControlFromConfig(cfg *Config, localDB, remoteDB *channeldb.DB,
 			homeChainConfig.Node)
 	}
 
+	// Override default fee estimator if an external service is specified.
+	if cfg.FeeURL != "" {
+		// Do not cache fees on regtest to make it easier to execute
+		// manual or automated test cases.
+		cacheFees := !cfg.Bitcoin.RegTest
+
+		ltndLog.Infof("Using external fee estimator %v: cached=%v",
+			cfg.FeeURL, cacheFees)
+
+		cc.feeEstimator = chainfee.NewWebAPIEstimator(
+			chainfee.SparseConfFeeSource{
+				URL: cfg.FeeURL,
+			},
+			!cacheFees,
+		)
+	}
+
 	// Start fee estimator.
 	if err := cc.feeEstimator.Start(); err != nil {
 		return nil, err

config.go

@@ -210,6 +210,8 @@ type Config struct {
 	MaxPendingChannels int    `long:"maxpendingchannels" description:"The maximum number of incoming pending channels permitted per peer."`
 	BackupFilePath     string `long:"backupfilepath" description:"The target location of the channel backup file"`
 
+	FeeURL string `long:"feeurl" description:"Optional URL for external fee estimation. If no URL is specified, the method for fee estimation will depend on the chosen backend and network."`
+
 	Bitcoin      *lncfg.Chain    `group:"Bitcoin" namespace:"bitcoin"`
 	BtcdMode     *lncfg.Btcd     `group:"btcd" namespace:"btcd"`
 	BitcoindMode *lncfg.Bitcoind `group:"bitcoind" namespace:"bitcoind"`

lncfg/neutrino.go

@@ -10,6 +10,6 @@ type Neutrino struct {
 	MaxPeers           int           `long:"maxpeers" description:"Max number of inbound and outbound peers"`
 	BanDuration        time.Duration `long:"banduration" description:"How long to ban misbehaving peers.  Valid time units are {s, m, h}.  Minimum 1 second"`
 	BanThreshold       uint32        `long:"banthreshold" description:"Maximum allowed ban score before disconnecting and banning misbehaving peers."`
-	FeeURL             string        `long:"feeurl" description:"Optional URL for fee estimation. If a URL is not specified, static fees will be used for estimation."`
+	FeeURL             string        `long:"feeurl" description:"DEPRECATED: Optional URL for fee estimation. If a URL is not specified, static fees will be used for estimation."`
 	AssertFilterHeader string        `long:"assertfilterheader" description:"Optional filter header in height:hash format to assert the state of neutrino's filter header chain on startup. If the assertion does not hold, then the filter header chain will be re-synced from the genesis block."`
 }