Fix linter issues

.golangci.yml

@@ -17,8 +17,13 @@ linters-settings:
 linters:
   enable-all: true
   disable:
-    # Init functions are used by loggers throughout the codebase.
-    - gochecknoinits
-
-    # Global variables are used by loggers.
     - gochecknoglobals
+    - gosec
+    - funlen
+    - maligned
+
+issues:
+  exclude-rules:
+    - path: cmd/chantools
+      linters:
+        - lll

btc/explorer_api.go

@@ -13,8 +13,8 @@ var (
 	ErrTxNotFound = errors.New("transaction not found")
 )
 
-type ExplorerApi struct {
+type ExplorerAPI struct {
-	BaseUrl string
+	BaseURL string
 }
 
 type TX struct {
@@ -51,15 +51,15 @@ type Status struct {
 	BlockHash   string `json:"block_hash"`
 }
 
-func (a *ExplorerApi) Transaction(txid string) (*TX, error) {
+func (a *ExplorerAPI) Transaction(txid string) (*TX, error) {
 	tx := &TX{}
-	err := fetchJSON(fmt.Sprintf("%s/tx/%s", a.BaseUrl, txid), tx)
+	err := fetchJSON(fmt.Sprintf("%s/tx/%s", a.BaseURL, txid), tx)
 	if err != nil {
 		return nil, err
 	}
 	for idx, vout := range tx.Vout {
 		url := fmt.Sprintf(
-			"%s/tx/%s/outspend/%d", a.BaseUrl, txid, idx,
+			"%s/tx/%s/outspend/%d", a.BaseURL, txid, idx,
 		)
 		outspend := Outspend{}
 		err := fetchJSON(url, &outspend)
@@ -71,12 +71,13 @@ func (a *ExplorerApi) Transaction(txid string) (*TX, error) {
 	return tx, nil
 }
 
-func (a *ExplorerApi) PublishTx(rawTxHex string) (string, error) {
+func (a *ExplorerAPI) PublishTx(rawTxHex string) (string, error) {
-	url := fmt.Sprintf("%s/tx", a.BaseUrl)
+	url := fmt.Sprintf("%s/tx", a.BaseURL)
 	resp, err := http.Post(url, "text/plain", strings.NewReader(rawTxHex))
 	if err != nil {
 		return "", err
 	}
+	defer resp.Body.Close()
 	body := new(bytes.Buffer)
 	_, err = body.ReadFrom(resp.Body)
 	if err != nil {
@@ -99,7 +100,7 @@ func fetchJSON(url string, target interface{}) error {
 	}
 	err = json.Unmarshal(body.Bytes(), target)
 	if err != nil {
-		if string(body.Bytes()) == "Transaction not found" {
+		if body.String() == "Transaction not found" {
 			return ErrTxNotFound
 		}
 	}

cmd/chantools/derivekey.go

@@ -19,9 +19,9 @@ func (c *deriveKeyCommand) Execute(_ []string) error {
 
 	var (
 		extendedKey *hdkeychain.ExtendedKey
-		err error
+		err         error
 	)
-	
+
 	// Check that root key is valid or fall back to console input.
 	switch {
 	case c.RootKey != "":

cmd/chantools/dumpbackup.go

@@ -20,7 +20,7 @@ func (c *dumpBackupCommand) Execute(_ []string) error {
 
 	var (
 		extendedKey *hdkeychain.ExtendedKey
-		err error
+		err         error
 	)
 
 	// Check that root key is valid or fall back to console input.

cmd/chantools/forceclose.go

@@ -27,7 +27,7 @@ type forceCloseCommand struct {
 func (c *forceCloseCommand) Execute(_ []string) error {
 	var (
 		extendedKey *hdkeychain.ExtendedKey
-		err error
+		err         error
 	)
 
 	// Check that root key is valid or fall back to console input.
@@ -67,7 +67,7 @@ func forceCloseChannels(extendedKey *hdkeychain.ExtendedKey,
 	if err != nil {
 		return err
 	}
-	chainApi := &btc.ExplorerApi{BaseUrl: cfg.ApiUrl}
+	api := &btc.ExplorerAPI{BaseURL: cfg.APIURL}
 	signer := &btc.Signer{ExtendedKey: extendedKey}
 
 	// Go through all channels in the DB, find the still open ones and
@@ -170,7 +170,7 @@ func forceCloseChannels(extendedKey *hdkeychain.ExtendedKey,
 
 		// Publish TX.
 		if publish {
-			response, err := chainApi.PublishTx(serialized)
+			response, err := api.PublishTx(serialized)
 			if err != nil {
 				return err
 			}

cmd/chantools/main.go

@@ -5,28 +5,28 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
-	"github.com/btcsuite/btcutil/hdkeychain"
-	"github.com/lightningnetwork/lnd/aezeed"
-	"golang.org/x/crypto/ssh/terminal"
 	"io/ioutil"
 	"os"
 	"strings"
 	"syscall"
 
 	"github.com/btcsuite/btcd/chaincfg"
+	"github.com/btcsuite/btcutil/hdkeychain"
 	"github.com/guggero/chantools/dataformat"
 	"github.com/jessevdk/go-flags"
+	"github.com/lightningnetwork/lnd/aezeed"
 	"github.com/lightningnetwork/lnd/build"
 	"github.com/lightningnetwork/lnd/channeldb"
+	"golang.org/x/crypto/ssh/terminal"
 )
 
 const (
-	defaultApiUrl = "https://blockstream.info/api"
+	defaultAPIURL = "https://blockstream.info/api"
 )
 
 type config struct {
 	Testnet         bool   `long:"testnet" description:"Set to true if testnet parameters should be used."`
-	ApiUrl          string `long:"apiurl" description:"API URL to use (must be esplora compatible)."`
+	APIURL          string `long:"apiurl" description:"API URL to use (must be esplora compatible)."`
 	ListChannels    string `long:"listchannels" description:"The channel input is in the format of lncli's listchannels format. Specify '-' to read from stdin."`
 	PendingChannels string `long:"pendingchannels" description:"The channel input is in the format of lncli's pendingchannels format. Specify '-' to read from stdin."`
 	FromSummary     string `long:"fromsummary" description:"The channel input is in the format of this tool's channel summary. Specify '-' to read from stdin."`
@@ -37,7 +37,7 @@ var (
 	logWriter = build.NewRotatingLogWriter()
 	log       = build.NewSubLogger("CHAN", logWriter.GenSubLogger)
 	cfg       = &config{
-		ApiUrl: defaultApiUrl,
+		APIURL: defaultAPIURL,
 	}
 	chainParams = &chaincfg.MainNetParams
 )
@@ -184,7 +184,7 @@ func rootKeyFromConsole() (*hdkeychain.ExtendedKey, error) {
 	}
 
 	var mnemonic aezeed.Mnemonic
-	copy(mnemonic[:], cipherSeedMnemonic[:])
+	copy(mnemonic[:], cipherSeedMnemonic)
 
 	// If we're unable to map it back into the ciphertext, then either the
 	// mnemonic is wrong, or the passphrase is wrong.

cmd/chantools/rescueclosed.go

@@ -39,7 +39,7 @@ type rescueClosedCommand struct {
 func (c *rescueClosedCommand) Execute(_ []string) error {
 	var (
 		extendedKey *hdkeychain.ExtendedKey
-		err error
+		err         error
 	)
 
 	// Check that root key is valid or fall back to console input.
@@ -169,7 +169,7 @@ func addrInCache(addr string, perCommitPoint *btcec.PublicKey) (string, error) {
 			tweakedPubKey.SerializeCompressed(),
 		)
 		equal := subtle.ConstantTimeCompare(
-			targetPubKeyHash[:], hashedPubKey[:],
+			targetPubKeyHash, hashedPubKey,
 		)
 		if equal == 1 {
 			wif, err := btcutil.NewWIF(

cmd/chantools/summary.go

@@ -18,19 +18,19 @@ func (c *summaryCommand) Execute(_ []string) error {
 	if err != nil {
 		return err
 	}
-	return summarizeChannels(cfg.ApiUrl, entries)
+	return summarizeChannels(cfg.APIURL, entries)
 }
 
-func summarizeChannels(apiUrl string,
+func summarizeChannels(apiURL string,
 	channels []*dataformat.SummaryEntry) error {
 
 	summaryFile := &dataformat.SummaryEntryFile{
 		Channels: channels,
 	}
-	chainApi := &btc.ExplorerApi{BaseUrl: apiUrl}
+	api := &btc.ExplorerAPI{BaseURL: apiURL}
 
 	for idx, channel := range channels {
-		tx, err := chainApi.Transaction(channel.FundingTXID)
+		tx, err := api.Transaction(channel.FundingTXID)
 		if err == btc.ErrTxNotFound {
 			log.Errorf("Funding TX %s not found. Ignoring.",
 				channel.FundingTXID)
@@ -52,7 +52,7 @@ func summarizeChannels(apiUrl string,
 			}
 
 			err := reportOutspend(
-				chainApi, summaryFile, channel, outspend,
+				api, summaryFile, channel, outspend,
 			)
 			if err != nil {
 				log.Errorf("Problem with channel %d (%s): %v.",
@@ -104,7 +104,7 @@ func summarizeChannels(apiUrl string,
 	return ioutil.WriteFile(fileName, summaryBytes, 0644)
 }
 
-func reportOutspend(api *btc.ExplorerApi,
+func reportOutspend(api *btc.ExplorerAPI,
 	summaryFile *dataformat.SummaryEntryFile,
 	entry *dataformat.SummaryEntry, os *btc.Outspend) error {
 
@@ -150,7 +150,7 @@ func reportOutspend(api *btc.ExplorerApi,
 			// Could maybe be brute forced.
 			if len(utxo) == 1 &&
 				utxo[0].ScriptPubkeyType == "v0_p2wpkh" &&
-				utxo[0].Outspend.Spent == false {
+				!utxo[0].Outspend.Spent {
 
 				entry.ClosingTX.OurAddr = utxo[0].ScriptPubkeyAddr
 			}

cmd/chantools/sweeptimelock.go

@@ -29,7 +29,7 @@ type sweepTimeLockCommand struct {
 func (c *sweepTimeLockCommand) Execute(_ []string) error {
 	var (
 		extendedKey *hdkeychain.ExtendedKey
-		err error
+		err         error
 	)
 
 	// Check that root key is valid or fall back to console input.
@@ -60,12 +60,12 @@ func (c *sweepTimeLockCommand) Execute(_ []string) error {
 		c.MaxCsvLimit = 2000
 	}
 	return sweepTimeLock(
-		extendedKey, cfg.ApiUrl, entries, c.SweepAddr, c.MaxCsvLimit,
+		extendedKey, cfg.APIURL, entries, c.SweepAddr, c.MaxCsvLimit,
 		c.Publish,
 	)
 }
 
-func sweepTimeLock(extendedKey *hdkeychain.ExtendedKey, apiUrl string,
+func sweepTimeLock(extendedKey *hdkeychain.ExtendedKey, apiURL string,
 	entries []*dataformat.SummaryEntry, sweepAddr string, maxCsvTimeout int,
 	publish bool) error {
 
@@ -74,7 +74,7 @@ func sweepTimeLock(extendedKey *hdkeychain.ExtendedKey, apiUrl string,
 		ExtendedKey: extendedKey,
 		ChainParams: chainParams,
 	}
-	chainApi := &btc.ExplorerApi{BaseUrl: apiUrl}
+	api := &btc.ExplorerAPI{BaseURL: apiURL}
 
 	sweepTx := wire.NewMsgTx(2)
 	totalOutputValue := int64(0)
@@ -230,7 +230,7 @@ func sweepTimeLock(extendedKey *hdkeychain.ExtendedKey, apiUrl string,
 
 	// Publish TX.
 	if publish {
-		response, err := chainApi.PublishTx(
+		response, err := api.PublishTx(
 			hex.EncodeToString(buf.Bytes()),
 		)
 		if err != nil {

dataformat/input.go

@@ -171,7 +171,7 @@ func fundingTXID(chanPoint string) string {
 func fundingTXIndex(chanPoint string) uint32 {
 	parts := strings.Split(chanPoint, ":")
 	if len(parts) != 2 {
-		panic(fmt.Errorf("channel point not in format <txid>:<idx>",
+		panic(fmt.Errorf("channel point %s not in format <txid>:<idx>",
 			chanPoint))
 	}
 	return uint32(parseInt(parts[1]))