Merge pull request #7765 from ErikEk/retire-io-ioutil-dep

Remove io/ioutil package dependency

cert/selfsigned.go

@@ -9,7 +9,6 @@ import (
 	"crypto/x509/pkix"
 	"encoding/pem"
 	"fmt"
-	"io/ioutil"
 	"math/big"
 	"net"
 	"os"
@@ -295,14 +294,14 @@ func GenCertPair(org string, tlsExtraIPs, tlsExtraDomains []string,
 func WriteCertPair(certFile, keyFile string, certBytes, keyBytes []byte) error {
 	// Write cert and key files.
 	if certFile != "" {
-		err := ioutil.WriteFile(certFile, certBytes, 0644)
+		err := os.WriteFile(certFile, certBytes, 0644)
 		if err != nil {
 			return err
 		}
 	}
 
 	if keyFile != "" {
-		err := ioutil.WriteFile(keyFile, keyBytes, 0600)
+		err := os.WriteFile(keyFile, keyBytes, 0600)
 		if err != nil {
 			os.Remove(certFile)
 			return err

cert/selfsigned_test.go

@@ -1,7 +1,7 @@
 package cert_test
 
 import (
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"testing"
 	"time"
@@ -42,10 +42,10 @@ func TestIsOutdatedCert(t *testing.T) {
 	// number of IPs and domains.
 	for numIPs := 1; numIPs <= len(extraIPs); numIPs++ {
 		for numDomains := 1; numDomains <= len(extraDomains); numDomains++ {
-			certBytes, err := ioutil.ReadFile(certPath)
+			certBytes, err := os.ReadFile(certPath)
 			require.NoError(t, err)
 
-			keyBytes, err := ioutil.ReadFile(keyPath)
+			keyBytes, err := os.ReadFile(keyPath)
 			require.NoError(t, err)
 
 			_, parsedCert, err := cert.LoadCertFromBytes(
@@ -98,10 +98,10 @@ func TestIsOutdatedPermutation(t *testing.T) {
 	err = cert.WriteCertPair(certPath, keyPath, certBytes, keyBytes)
 	require.NoError(t, err)
 
-	certBytes, err = ioutil.ReadFile(certPath)
+	certBytes, err = os.ReadFile(certPath)
 	require.NoError(t, err)
 
-	keyBytes, err = ioutil.ReadFile(keyPath)
+	keyBytes, err = os.ReadFile(keyPath)
 	require.NoError(t, err)
 
 	_, parsedCert, err := cert.LoadCertFromBytes(certBytes, keyBytes)
@@ -171,10 +171,10 @@ func TestTLSDisableAutofill(t *testing.T) {
 	require.NoError(t, err)
 
 	// Read certs from disk.
-	certBytes, err = ioutil.ReadFile(certPath)
+	certBytes, err = os.ReadFile(certPath)
 	require.NoError(t, err)
 
-	keyBytes, err = ioutil.ReadFile(keyPath)
+	keyBytes, err = os.ReadFile(keyPath)
 	require.NoError(t, err)
 
 	// Load the certificate.
@@ -230,10 +230,10 @@ func TestTLSConfig(t *testing.T) {
 	err = cert.WriteCertPair(certPath, keyPath, certBytes, keyBytes)
 	require.NoError(t, err)
 
-	certBytes, err = ioutil.ReadFile(certPath)
+	certBytes, err = os.ReadFile(certPath)
 	require.NoError(t, err)
 
-	keyBytes, err = ioutil.ReadFile(keyPath)
+	keyBytes, err = os.ReadFile(keyPath)
 	require.NoError(t, err)
 
 	// Load the certificate.

cert/tls.go

@@ -3,7 +3,7 @@ package cert
 import (
 	"crypto/tls"
 	"crypto/x509"
-	"io/ioutil"
+	"os"
 	"sync"
 )
 
@@ -31,11 +31,11 @@ var (
 func GetCertBytesFromPath(certPath, keyPath string) (certBytes,
 	keyBytes []byte, err error) {
 
-	certBytes, err = ioutil.ReadFile(certPath)
+	certBytes, err = os.ReadFile(certPath)
 	if err != nil {
 		return nil, nil, err
 	}
-	keyBytes, err = ioutil.ReadFile(keyPath)
+	keyBytes, err = os.ReadFile(keyPath)
 	if err != nil {
 		return nil, nil, err
 	}

chainreg/chainregistry.go

@@ -5,7 +5,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net"
 	"net/url"
 	"os"
@@ -547,7 +547,7 @@ func NewPartialChainControl(cfg *Config) (*PartialChainControl, func(), error) {
 			if err != nil {
 				return nil, nil, err
 			}
-			rpcCert, err = ioutil.ReadAll(certFile)
+			rpcCert, err = io.ReadAll(certFile)
 			if err != nil {
 				return nil, nil, err
 			}

chanbackup/backupfile.go

@@ -2,7 +2,6 @@ package chanbackup
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 
@@ -138,7 +137,7 @@ func (b *MultiFile) ExtractMulti(keyChain keychain.KeyRing) (*Multi, error) {
 	// Now that we've confirmed the target file is populated, we'll read
 	// all the contents of the file. This function ensures that file is
 	// always closed, even if we can't read the contents.
-	multiBytes, err := ioutil.ReadFile(b.fileName)
+	multiBytes, err := os.ReadFile(b.fileName)
 	if err != nil {
 		return nil, err
 	}

chanbackup/backupfile_test.go

@@ -3,7 +3,6 @@ package chanbackup
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
 	"math/rand"
 	"os"
 	"path/filepath"
@@ -27,7 +26,7 @@ func assertBackupMatches(t *testing.T, filePath string,
 
 	t.Helper()
 
-	packedBackup, err := ioutil.ReadFile(filePath)
+	packedBackup, err := os.ReadFile(filePath)
 	require.NoError(t, err, "unable to test file")
 
 	if !bytes.Equal(packedBackup, currentBackup) {

channeldb/migration/lnwire21/announcement_signatures.go

@@ -2,7 +2,6 @@ package lnwire
 
 import (
 	"io"
-	"io/ioutil"
 )
 
 // AnnounceSignatures is a direct message between two endpoints of a
@@ -66,7 +65,7 @@ func (a *AnnounceSignatures) Decode(r io.Reader, pver uint32) error {
 	// we'll collect the remainder into the ExtraOpaqueData field. If there
 	// aren't any bytes, then we'll snip off the slice to avoid carrying
 	// around excess capacity.
-	a.ExtraOpaqueData, err = ioutil.ReadAll(r)
+	a.ExtraOpaqueData, err = io.ReadAll(r)
 	if err != nil {
 		return err
 	}

channeldb/migration/lnwire21/channel_announcement.go

@@ -3,7 +3,6 @@ package lnwire
 import (
 	"bytes"
 	"io"
-	"io/ioutil"
 
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 )
@@ -89,7 +88,7 @@ func (a *ChannelAnnouncement) Decode(r io.Reader, pver uint32) error {
 	// we'll collect the remainder into the ExtraOpaqueData field. If there
 	// aren't any bytes, then we'll snip off the slice to avoid carrying
 	// around excess capacity.
-	a.ExtraOpaqueData, err = ioutil.ReadAll(r)
+	a.ExtraOpaqueData, err = io.ReadAll(r)
 	if err != nil {
 		return err
 	}

channeldb/migration/lnwire21/channel_update.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"fmt"
 	"io"
-	"io/ioutil"
 
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 )
@@ -160,7 +159,7 @@ func (a *ChannelUpdate) Decode(r io.Reader, pver uint32) error {
 	// we'll collect the remainder into the ExtraOpaqueData field. If there
 	// aren't any bytes, then we'll snip off the slice to avoid carrying
 	// around excess capacity.
-	a.ExtraOpaqueData, err = ioutil.ReadAll(r)
+	a.ExtraOpaqueData, err = io.ReadAll(r)
 	if err != nil {
 		return err
 	}

channeldb/migration/lnwire21/node_announcement.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"image/color"
 	"io"
-	"io/ioutil"
 	"net"
 	"unicode/utf8"
 )
@@ -127,7 +126,7 @@ func (a *NodeAnnouncement) Decode(r io.Reader, pver uint32) error {
 	// we'll collect the remainder into the ExtraOpaqueData field. If there
 	// aren't any bytes, then we'll snip off the slice to avoid carrying
 	// around excess capacity.
-	a.ExtraOpaqueData, err = ioutil.ReadAll(r)
+	a.ExtraOpaqueData, err = io.ReadAll(r)
 	if err != nil {
 		return err
 	}

cmd/lncli/cmd_macaroon.go

@@ -4,8 +4,8 @@ import (
 	"bytes"
 	"encoding/hex"
 	"fmt"
-	"io/ioutil"
 	"net"
+	"os"
 	"strconv"
 	"strings"
 	"unicode"
@@ -192,7 +192,7 @@ func bakeMacaroon(ctx *cli.Context) error {
 	// a file or write to the standard output using hex encoding.
 	switch {
 	case savePath != "":
-		err = ioutil.WriteFile(savePath, macBytes, 0644)
+		err = os.WriteFile(savePath, macBytes, 0644)
 		if err != nil {
 			return err
 		}
@@ -352,7 +352,7 @@ func printMacaroon(ctx *cli.Context) error {
 		macPath := lncfg.CleanAndExpandPath(ctx.String("macaroon_file"))
 
 		// Load the specified macaroon file.
-		macBytes, err = ioutil.ReadFile(macPath)
+		macBytes, err = os.ReadFile(macPath)
 		if err != nil {
 			return fmt.Errorf("unable to read macaroon path %v: %v",
 				macPath, err)
@@ -441,7 +441,7 @@ func constrainMacaroon(ctx *cli.Context) error {
 	sourceMacFile := lncfg.CleanAndExpandPath(args.First())
 	args = args.Tail()
 
-	sourceMacBytes, err := ioutil.ReadFile(sourceMacFile)
+	sourceMacBytes, err := os.ReadFile(sourceMacFile)
 	if err != nil {
 		return fmt.Errorf("error trying to read source macaroon file "+
 			"%s: %v", sourceMacFile, err)
@@ -471,7 +471,7 @@ func constrainMacaroon(ctx *cli.Context) error {
 	}
 
 	// Now we can output the result.
-	err = ioutil.WriteFile(destMacFile, destMacBytes, 0644)
+	err = os.WriteFile(destMacFile, destMacBytes, 0644)
 	if err != nil {
 		return fmt.Errorf("error writing destination macaroon file "+
 			"%s: %v", destMacFile, err)

cmd/lncli/cmd_open_channel.go

@@ -9,7 +9,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"strconv"
 	"strings"
@@ -1016,7 +1015,7 @@ func readTerminalOrFile(quit chan struct{}) (string, error) {
 
 	// If it's a path to an existing file and it's small enough, let's try
 	// to read its content now.
-	content, err := ioutil.ReadFile(maybeFile)
+	content, err := os.ReadFile(maybeFile)
 	if err != nil {
 		return "", err
 	}

cmd/lncli/cmd_payments.go

@@ -7,7 +7,7 @@ import (
 	"encoding/hex"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"os"
 	"runtime"
 	"strconv"
@@ -987,7 +987,7 @@ func sendToRoute(ctx *cli.Context) error {
 	// The user is signalling that we should read stdin in order to parse
 	// the set of target routes.
 	case args.Present() && args.First() == "-":
-		b, err := ioutil.ReadAll(os.Stdin)
+		b, err := io.ReadAll(os.Stdin)
 		if err != nil {
 			return err
 		}

cmd/lncli/cmd_profile.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path"
 	"strings"
@@ -423,7 +422,7 @@ func profileAddMacaroon(ctx *cli.Context) error {
 
 	// Now load and possibly encrypt the macaroon file.
 	macPath := lncfg.CleanAndExpandPath(ctx.GlobalString("macaroonpath"))
-	macBytes, err := ioutil.ReadFile(macPath)
+	macBytes, err := os.ReadFile(macPath)
 	if err != nil {
 		return fmt.Errorf("unable to read macaroon path: %w", err)
 	}

cmd/lncli/cmd_walletunlocker.go

@@ -5,7 +5,6 @@ import (
 	"bytes"
 	"encoding/hex"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"strconv"
 	"strings"
@@ -712,7 +711,7 @@ func createWatchOnly(ctx *cli.Context) error {
 	}
 
 	jsonFile := lncfg.CleanAndExpandPath(ctx.Args().First())
-	jsonBytes, err := ioutil.ReadFile(jsonFile)
+	jsonBytes, err := os.ReadFile(jsonFile)
 	if err != nil {
 		return fmt.Errorf("error reading JSON from file %v: %v",
 			jsonFile, err)

cmd/lncli/commands.go

@@ -9,7 +9,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"math"
 	"os"
 	"strconv"
@@ -2833,7 +2832,7 @@ func parseChanBackups(ctx *cli.Context) (*lnrpc.RestoreChanBackupRequest, error)
 		}, nil
 
 	case ctx.IsSet("multi_file"):
-		packedMulti, err := ioutil.ReadFile(ctx.String("multi_file"))
+		packedMulti, err := os.ReadFile(ctx.String("multi_file"))
 		if err != nil {
 			return nil, fmt.Errorf("unable to decode multi packed "+
 				"backup: %v", err)

cmd/lncli/profile.go

@@ -6,7 +6,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"path"
 	"strings"
 
@@ -129,7 +129,7 @@ func profileFromContext(ctx *cli.Context, store, skipMacaroons bool) (
 	var tlsCert []byte
 	if tlsCertPath != "" && !insecure {
 		var err error
-		tlsCert, err = ioutil.ReadFile(tlsCertPath)
+		tlsCert, err = os.ReadFile(tlsCertPath)
 		if err != nil {
 			return nil, fmt.Errorf("could not load TLS cert "+
 				"file: %v", err)
@@ -167,7 +167,7 @@ func profileFromContext(ctx *cli.Context, store, skipMacaroons bool) (
 	}
 
 	// Now load and possibly encrypt the macaroon file.
-	macBytes, err := ioutil.ReadFile(macPath)
+	macBytes, err := os.ReadFile(macPath)
 	if err != nil {
 		return nil, fmt.Errorf("unable to read macaroon path (check "+
 			"the network setting!): %v", err)
@@ -222,7 +222,7 @@ func loadProfileFile(file string) (*profileFile, error) {
 		return nil, errNoProfileFile
 	}
 
-	content, err := ioutil.ReadFile(file)
+	content, err := os.ReadFile(file)
 	if err != nil {
 		return nil, fmt.Errorf("could not load profile file %s: %w",
 			file, err)
@@ -243,7 +243,8 @@ func saveProfileFile(file string, f *profileFile) error {
 	if err != nil {
 		return fmt.Errorf("could not marshal profile: %w", err)
 	}
-	return ioutil.WriteFile(file, content, 0644)
+
+	return os.WriteFile(file, content, 0644)
 }
 
 // profileFile is a struct that represents the whole content of a profile file.

config.go

@@ -8,7 +8,7 @@ import (
 	"encoding/hex"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net"
 	"os"
 	"os/user"
@@ -1845,7 +1845,7 @@ func parseRPCParams(cConfig *lncfg.Chain, nodeConfig interface{},
 
 		// We convert the cookie into a user name and password.
 		if conf.RPCCookie != "" {
-			cookie, err := ioutil.ReadFile(conf.RPCCookie)
+			cookie, err := os.ReadFile(conf.RPCCookie)
 			if err != nil {
 				return fmt.Errorf("cannot read cookie file: %w",
 					err)
@@ -2006,7 +2006,7 @@ func extractBtcdRPCParams(btcdConfigPath string) (string, string, error) {
 
 	// With the file open extract the contents of the configuration file so
 	// we can attempt to locate the RPC credentials.
-	configContents, err := ioutil.ReadAll(btcdConfigFile)
+	configContents, err := io.ReadAll(btcdConfigFile)
 	if err != nil {
 		return "", "", err
 	}
@@ -2056,7 +2056,7 @@ func extractBitcoindRPCParams(networkName, bitcoindDataDir, bitcoindConfigPath,
 
 	// With the file open extract the contents of the configuration file so
 	// we can attempt to locate the RPC credentials.
-	configContents, err := ioutil.ReadAll(bitcoindConfigFile)
+	configContents, err := io.ReadAll(bitcoindConfigFile)
 	if err != nil {
 		return "", "", "", "", err
 	}
@@ -2118,7 +2118,7 @@ func extractBitcoindRPCParams(networkName, bitcoindDataDir, bitcoindConfigPath,
 	if rpcCookiePath != "" {
 		cookiePath = rpcCookiePath
 	}
-	cookie, err := ioutil.ReadFile(cookiePath)
+	cookie, err := os.ReadFile(cookiePath)
 	if err == nil {
 		splitCookie := strings.Split(string(cookie), ":")
 		if len(splitCookie) == 2 {

config_builder.go

@@ -6,7 +6,6 @@ import (
 	"database/sql"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"os"
 	"path/filepath"
@@ -329,7 +328,7 @@ func (d *DefaultWalletImpl) BuildWalletConfig(ctx context.Context,
 	case d.cfg.WalletUnlockPasswordFile != "" && walletExists:
 		d.logger.Infof("Attempting automatic wallet unlock with " +
 			"password provided in file")
-		pwBytes, err := ioutil.ReadFile(d.cfg.WalletUnlockPasswordFile)
+		pwBytes, err := os.ReadFile(d.cfg.WalletUnlockPasswordFile)
 		if err != nil {
 			return nil, nil, nil, fmt.Errorf("error reading "+
 				"password from file %s: %v",

contractcourt/htlc_incoming_contest_resolver_test.go

@@ -3,7 +3,6 @@ package contractcourt
 import (
 	"bytes"
 	"io"
-	"io/ioutil"
 	"testing"
 
 	sphinx "github.com/lightningnetwork/lightning-onion"
@@ -291,7 +290,7 @@ type mockOnionProcessor struct {
 func (o *mockOnionProcessor) ReconstructHopIterator(r io.Reader, rHash []byte,
 	_ hop.ReconstructBlindingInfo) (hop.Iterator, error) {
 
-	data, err := ioutil.ReadAll(r)
+	data, err := io.ReadAll(r)
 	if err != nil {
 		return nil, err
 	}

docs/release-notes/release-notes-0.18.0.md

@@ -398,7 +398,10 @@ bitcoin peers' feefilter values into account](https://github.com/lightningnetwor
   In particular, the complexity involved in the lifecycle loop has been
   decoupled into logical steps, with each step having its own responsibility,
   making it easier to reason about the payment flow.
- 
+
+* [Remove io/ioutil package 
+  dependence](https://github.com/lightningnetwork/lnd/pull/7765).
+
 * [Add a watchtower tower client
   multiplexer](https://github.com/lightningnetwork/lnd/pull/7702) to manage
   tower clients of different types.

htlcswitch/mock.go

@@ -7,7 +7,6 @@ import (
 	"encoding/binary"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net"
 	"os"
 	"path/filepath"
@@ -947,7 +946,7 @@ var _ ChannelLink = (*mockChannelLink)(nil)
 func newDB() (*channeldb.DB, func(), error) {
 	// First, create a temporary directory to be used for the duration of
 	// this test.
-	tempDirName, err := ioutil.TempDir("", "channeldb")
+	tempDirName, err := os.MkdirTemp("", "channeldb")
 	if err != nil {
 		return nil, nil, err
 	}

internal/musig2v040/musig2_test.go

@@ -10,7 +10,7 @@ import (
 	"errors"
 	"flag"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"sync"
 	"testing"
 
@@ -256,7 +256,7 @@ func TestMuSig2KeyAggTestVectors(t *testing.T) {
 
 		var formattedJson bytes.Buffer
 		json.Indent(&formattedJson, jsonBytes, "", "\t")
-		err = ioutil.WriteFile(
+		err = os.WriteFile(
 			keyAggTestVectorName, formattedJson.Bytes(), 0644,
 		)
 		if err != nil {
@@ -656,7 +656,7 @@ func TestMuSig2SigningTestVectors(t *testing.T) {
 
 		var formattedJson bytes.Buffer
 		json.Indent(&formattedJson, jsonBytes, "", "\t")
-		err = ioutil.WriteFile(
+		err = os.WriteFile(
 			signTestVectorName, formattedJson.Bytes(), 0644,
 		)
 		if err != nil {
@@ -1540,7 +1540,7 @@ func TestMusig2AggregateNoncesTestVectors(t *testing.T) {
 
 		var formattedJson bytes.Buffer
 		json.Indent(&formattedJson, jsonBytes, "", "\t")
-		err = ioutil.WriteFile(
+		err = os.WriteFile(
 			nonceAggTestVectorName, formattedJson.Bytes(), 0644,
 		)
 		if err != nil {

itest/lnd_channel_backup_test.go

@@ -3,7 +3,6 @@ package itest
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -285,7 +284,7 @@ func testChannelBackupRestoreBasic(ht *lntest.HarnessTest) {
 
 				// Read the entire Multi backup stored within
 				// this node's channel.backup file.
-				multi, err := ioutil.ReadFile(backupFilePath)
+				multi, err := os.ReadFile(backupFilePath)
 				require.NoError(st, err)
 
 				// Now that we have Dave's backup file, we'll
@@ -376,7 +375,7 @@ func testChannelBackupRestoreBasic(ht *lntest.HarnessTest) {
 
 				// Read the entire Multi backup stored within
 				// this node's channel.backup file.
-				multi, err := ioutil.ReadFile(backupFilePath)
+				multi, err := os.ReadFile(backupFilePath)
 				require.NoError(st, err)
 
 				// Now that we have Dave's backup file, we'll
@@ -501,7 +500,7 @@ func runChanRestoreScenarioUnConfirmed(ht *lntest.HarnessTest, useFile bool) {
 		backupFilePath := dave.Cfg.ChanBackupPath()
 		// Read the entire Multi backup stored within this node's
 		// channel.backup file.
-		multi, err = ioutil.ReadFile(backupFilePath)
+		multi, err = os.ReadFile(backupFilePath)
 		require.NoError(ht, err)
 	} else {
 		// For this restoration method, we'll grab the current
@@ -646,7 +645,7 @@ func runChanRestoreScenarioCommitTypes(ht *lntest.HarnessTest,
 
 	// Read the entire Multi backup stored within this node's
 	// channels.backup file.
-	multi, err := ioutil.ReadFile(backupFilePath)
+	multi, err := os.ReadFile(backupFilePath)
 	require.NoError(ht, err)
 
 	// If this was a zero conf taproot channel, then since it's private,
@@ -774,7 +773,7 @@ func runChanRestoreScenarioForceClose(ht *lntest.HarnessTest, zeroConf bool) {
 
 	// Read the entire Multi backup stored within this node's
 	// channel.backup file.
-	multi, err := ioutil.ReadFile(backupFilePath)
+	multi, err := os.ReadFile(backupFilePath)
 	require.NoError(ht, err)
 
 	// Now that we have Dave's backup file, we'll create a new nodeRestorer
@@ -907,7 +906,7 @@ func testChannelBackupUpdates(ht *lntest.HarnessTest) {
 	// the on disk back up file to our currentBackup pointer above.
 	assertBackupFileState := func() {
 		err := wait.NoError(func() error {
-			packedBackup, err := ioutil.ReadFile(backupFilePath)
+			packedBackup, err := os.ReadFile(backupFilePath)
 			if err != nil {
 				return fmt.Errorf("unable to read backup "+
 					"file: %v", err)

itest/lnd_misc_test.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"encoding/hex"
 	"fmt"
-	"io/ioutil"
+	"os"
 
 	"github.com/btcsuite/btcd/btcutil"
 	"github.com/btcsuite/btcd/txscript"
@@ -708,7 +708,7 @@ func testAbandonChannel(ht *lntest.HarnessTest) {
 	// To make sure the channel is removed from the backup file as well
 	// when being abandoned, grab a backup snapshot so we can compare it
 	// with the later state.
-	bkupBefore, err := ioutil.ReadFile(alice.Cfg.ChanBackupPath())
+	bkupBefore, err := os.ReadFile(alice.Cfg.ChanBackupPath())
 	require.NoError(ht, err, "channel backup before abandoning channel")
 
 	// Send request to abandon channel.
@@ -733,7 +733,7 @@ func testAbandonChannel(ht *lntest.HarnessTest) {
 
 	// Make sure the channel is no longer in the channel backup list.
 	err = wait.NoError(func() error {
-		bkupAfter, err := ioutil.ReadFile(alice.Cfg.ChanBackupPath())
+		bkupAfter, err := os.ReadFile(alice.Cfg.ChanBackupPath())
 		if err != nil {
 			return fmt.Errorf("could not get channel backup "+
 				"before abandoning channel: %v", err)

kvdb/backend.go

@@ -9,7 +9,6 @@ import (
 	"encoding/binary"
 	"encoding/hex"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"time"
@@ -218,7 +217,7 @@ func lastCompactionDate(dbFile string) (time.Time, error) {
 		return zeroTime, nil
 	}
 
-	tsBytes, err := ioutil.ReadFile(tsFile)
+	tsBytes, err := os.ReadFile(tsFile)
 	if err != nil {
 		return zeroTime, err
 	}
@@ -235,7 +234,7 @@ func updateLastCompactionDate(dbFile string) error {
 	byteOrder.PutUint64(tsBytes[:], uint64(time.Now().UnixNano()))
 
 	tsFile := fmt.Sprintf("%s%s", dbFile, LastCompactionFileNameSuffix)
-	return ioutil.WriteFile(tsFile, tsBytes[:], 0600)
+	return os.WriteFile(tsFile, tsBytes[:], 0600)
 }
 
 // GetTestBackend opens (or creates if doesn't exist) a bbolt or etcd

lnd.go

@@ -8,7 +8,6 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/http/pprof"
@@ -83,7 +82,7 @@ func AdminAuthOptions(cfg *Config, skipMacaroons bool) ([]grpc.DialOption,
 	// Get the admin macaroon if macaroons are active.
 	if !skipMacaroons && !cfg.NoMacaroons {
 		// Load the admin macaroon file.
-		macBytes, err := ioutil.ReadFile(cfg.AdminMacPath)
+		macBytes, err := os.ReadFile(cfg.AdminMacPath)
 		if err != nil {
 			return nil, fmt.Errorf("unable to read macaroon "+
 				"path (check the network setting!): %v", err)

lnrpc/chainrpc/chain_server.go

@@ -7,7 +7,6 @@ import (
 	"bytes"
 	"context"
 	"errors"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"sync"
@@ -153,7 +152,7 @@ func New(cfg *Config) (*Server, lnrpc.MacaroonPerms, error) {
 		if err != nil {
 			return nil, nil, err
 		}
-		err = ioutil.WriteFile(macFilePath, chainNotifierMacBytes, 0644)
+		err = os.WriteFile(macFilePath, chainNotifierMacBytes, 0644)
 		if err != nil {
 			_ = os.Remove(macFilePath)
 			return nil, nil, err

lnrpc/invoicesrpc/invoices_server.go

@@ -7,7 +7,6 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 
@@ -132,7 +131,7 @@ func New(cfg *Config) (*Server, lnrpc.MacaroonPerms, error) {
 		if err != nil {
 			return nil, nil, err
 		}
-		err = ioutil.WriteFile(macFilePath, invoicesMacBytes, 0644)
+		err = os.WriteFile(macFilePath, invoicesMacBytes, 0644)
 		if err != nil {
 			_ = os.Remove(macFilePath)
 			return nil, nil, err

lnrpc/routerrpc/router_server.go

@@ -6,7 +6,6 @@ import (
 	crand "crypto/rand"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"sync/atomic"
@@ -216,7 +215,7 @@ func New(cfg *Config) (*Server, lnrpc.MacaroonPerms, error) {
 		if err != nil {
 			return nil, nil, err
 		}
-		err = ioutil.WriteFile(macFilePath, routerMacBytes, 0644)
+		err = os.WriteFile(macFilePath, routerMacBytes, 0644)
 		if err != nil {
 			_ = os.Remove(macFilePath)
 			return nil, nil, err

lnrpc/signrpc/signer_server.go

@@ -8,7 +8,6 @@ import (
 	"context"
 	"crypto/sha256"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 
@@ -167,7 +166,7 @@ func New(cfg *Config) (*Server, lnrpc.MacaroonPerms, error) {
 		if err != nil {
 			return nil, nil, err
 		}
-		err = ioutil.WriteFile(macFilePath, signerMacBytes, 0644)
+		err = os.WriteFile(macFilePath, signerMacBytes, 0644)
 		if err != nil {
 			_ = os.Remove(macFilePath)
 			return nil, nil, err

lnrpc/walletrpc/walletkit_server.go

@@ -10,7 +10,6 @@ import (
 	"encoding/binary"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"math"
 	"os"
 	"path/filepath"
@@ -289,7 +288,7 @@ func New(cfg *Config) (*WalletKit, lnrpc.MacaroonPerms, error) {
 		if err != nil {
 			return nil, nil, err
 		}
-		err = ioutil.WriteFile(macFilePath, walletKitMacBytes, 0644)
+		err = os.WriteFile(macFilePath, walletKitMacBytes, 0644)
 		if err != nil {
 			_ = os.Remove(macFilePath)
 			return nil, nil, err

lntest/bitcoind_common.go

@@ -6,7 +6,6 @@ package lntest
 import (
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -105,7 +104,7 @@ func newBackend(miner string, netParams *chaincfg.Params, extraArgs []string,
 		return nil, nil, err
 	}
 
-	tempBitcoindDir, err := ioutil.TempDir("", "bitcoind")
+	tempBitcoindDir, err := os.MkdirTemp("", "bitcoind")
 	if err != nil {
 		return nil, nil,
 			fmt.Errorf("unable to create temp directory: %w", err)

lntest/btcd.go

@@ -7,7 +7,6 @@ import (
 	"encoding/hex"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"strings"
 
@@ -135,7 +134,7 @@ func NewBackend(miner string, netParams *chaincfg.Params) (
 		// the log files, including any compressed log files from
 		// logrorate, before deleting the temporary log dir.
 		logDir := fmt.Sprintf("%s/%s", baseLogDir, netParams.Name)
-		files, err := ioutil.ReadDir(logDir)
+		files, err := os.ReadDir(logDir)
 		if err != nil {
 			errStr += fmt.Sprintf(
 				"unable to read log directory: %v\n", err,

lntest/harness_miner.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -121,7 +120,7 @@ func (h *HarnessMiner) saveLogs() {
 	// After shutting down the miner, we'll make a copy of the log files
 	// before deleting the temporary log dir.
 	path := fmt.Sprintf("%s/%s", h.logPath, harnessNetParams.Name)
-	files, err := ioutil.ReadDir(path)
+	files, err := os.ReadDir(path)
 	require.NoError(h, err, "unable to read log directory")
 
 	for _, file := range files {

lntest/node/harness_node.go

@@ -9,7 +9,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -297,7 +296,7 @@ func (hn *HarnessNode) ReadMacaroon(macPath string, timeout time.Duration) (
 	// using it.
 	var mac *macaroon.Macaroon
 	err := wait.NoError(func() error {
-		macBytes, err := ioutil.ReadFile(macPath)
+		macBytes, err := os.ReadFile(macPath)
 		if err != nil {
 			return fmt.Errorf("error reading macaroon file: %w",
 				err)
@@ -824,7 +823,7 @@ func (hn *HarnessNode) BackupDB() error {
 		}
 	} else {
 		// Backup files.
-		tempDir, err := ioutil.TempDir("", "past-state")
+		tempDir, err := os.MkdirTemp("", "past-state")
 		if err != nil {
 			return fmt.Errorf("unable to create temp db folder: %w",
 				err)
@@ -1032,7 +1031,7 @@ func addLogFile(hn *HarnessNode) error {
 // copyAll copies all files and directories from srcDir to dstDir recursively.
 // Note that this function does not support links.
 func copyAll(dstDir, srcDir string) error {
-	entries, err := ioutil.ReadDir(srcDir)
+	entries, err := os.ReadDir(srcDir)
 	if err != nil {
 		return err
 	}

lnwallet/rpcwallet/rpcwallet.go

@@ -7,7 +7,7 @@ import (
 	"crypto/x509"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"time"
 
 	"github.com/btcsuite/btcd/btcec/v2"
@@ -1259,7 +1259,7 @@ func extractSignature(in *psbt.PInput,
 func connectRPC(hostPort, tlsCertPath, macaroonPath string,
 	timeout time.Duration) (*grpc.ClientConn, error) {
 
-	certBytes, err := ioutil.ReadFile(tlsCertPath)
+	certBytes, err := os.ReadFile(tlsCertPath)
 	if err != nil {
 		return nil, fmt.Errorf("error reading TLS cert file %v: %w",
 			tlsCertPath, err)
@@ -1271,7 +1271,7 @@ func connectRPC(hostPort, tlsCertPath, macaroonPath string,
 			"certificate")
 	}
 
-	macBytes, err := ioutil.ReadFile(macaroonPath)
+	macBytes, err := os.ReadFile(macaroonPath)
 	if err != nil {
 		return nil, fmt.Errorf("error reading macaroon file %v: %w",
 			macaroonPath, err)

lnwallet/transactions_test.go

@@ -8,8 +8,8 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net"
+	"os"
 	"sort"
 	"strings"
 	"testing"
@@ -229,7 +229,7 @@ func TestCommitmentAndHTLCTransactions(t *testing.T) {
 
 		var testCases []testCase
 
-		jsonText, err := ioutil.ReadFile(set.jsonFile)
+		jsonText, err := os.ReadFile(set.jsonFile)
 		require.NoError(t, err)
 
 		err = json.Unmarshal(jsonText, &testCases)

lnwire/onion_error.go

@@ -7,7 +7,6 @@ import (
 	"encoding/binary"
 	"fmt"
 	"io"
-	"io/ioutil"
 
 	"github.com/davecgh/go-spew/spew"
 	"github.com/go-errors/errors"
@@ -1304,7 +1303,7 @@ func DecodeFailure(r io.Reader, pver uint32) (FailureMessage, error) {
 		return nil, fmt.Errorf("unable to read pad len: %w", err)
 	}
 
-	if _, err := io.CopyN(ioutil.Discard, r, int64(padLength)); err != nil {
+	if _, err := io.CopyN(io.Discard, r, int64(padLength)); err != nil {
 		return nil, fmt.Errorf("unable to read padding %w", err)
 	}
 

routing/pathfind_test.go

@@ -8,9 +8,9 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"math"
 	"net"
+	"os"
 	"reflect"
 	"strings"
 	"testing"
@@ -183,7 +183,7 @@ func makeTestGraph(t *testing.T, useCache bool) (*channeldb.ChannelGraph,
 func parseTestGraph(t *testing.T, useCache bool, path string) (
 	*testGraphInstance, error) {
 
-	graphJSON, err := ioutil.ReadFile(path)
+	graphJSON, err := os.ReadFile(path)
 	if err != nil {
 		return nil, err
 	}

tls_manager.go

@@ -7,7 +7,6 @@ import (
 	"crypto/x509"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"os"
@@ -279,7 +278,7 @@ func (t *TLSManager) ensureEncryption(keyRing keychain.SecretKeyRing) error {
 		if err != nil {
 			return err
 		}
-		err = ioutil.WriteFile(
+		err = os.WriteFile(
 			t.cfg.TLSKeyPath, b.Bytes(), modifyFilePermissions,
 		)
 		if err != nil {

tls_manager_test.go

@@ -9,9 +9,9 @@ import (
 	"crypto/x509"
 	"crypto/x509/pkix"
 	"encoding/pem"
-	"io/ioutil"
 	"math/big"
 	"net"
+	"os"
 	"testing"
 	"time"
 
@@ -199,7 +199,7 @@ func TestGenerateEphemeralCert(t *testing.T) {
 	keyBytes, err := tlsManager.loadEphemeralCertificate()
 	require.NoError(t, err, "failed to generate new certificate")
 
-	certBytes, err := ioutil.ReadFile(tmpCertPath)
+	certBytes, err := os.ReadFile(tmpCertPath)
 	require.NoError(t, err)
 
 	tlsr, err := cert.NewTLSReloader(certBytes, keyBytes)
@@ -207,15 +207,15 @@ func TestGenerateEphemeralCert(t *testing.T) {
 	tlsManager.tlsReloader = tlsr
 
 	// Make sure .tmp file is created at the tmp cert path.
-	_, err = ioutil.ReadFile(tmpCertPath)
+	_, err = os.ReadFile(tmpCertPath)
 	require.NoError(t, err, "couldn't find temp cert file")
 
 	// But no key should be stored.
-	_, err = ioutil.ReadFile(cfg.TLSKeyPath)
+	_, err = os.ReadFile(cfg.TLSKeyPath)
 	require.Error(t, err, "shouldn't have found file")
 
 	// And no permanent cert file should be stored.
-	_, err = ioutil.ReadFile(cfg.TLSCertPath)
+	_, err = os.ReadFile(cfg.TLSCertPath)
 	require.Error(t, err, "shouldn't have found a permanent cert file")
 
 	// Now test that when we reload the certificate it generates the new
@@ -350,9 +350,9 @@ func writeTestCertFiles(t *testing.T, expiredCert, encryptTLSKey bool,
 		require.NoError(t, err, "failed to encrypt private key")
 	}
 
-	err = ioutil.WriteFile(tempDir+"/tls.cert", certBuf.Bytes(), 0644)
+	err = os.WriteFile(tempDir+"/tls.cert", certBuf.Bytes(), 0644)
 	require.NoError(t, err, "failed to write cert file")
-	err = ioutil.WriteFile(tempDir+"/tls.key", keyBuf.Bytes(), 0600)
+	err = os.WriteFile(tempDir+"/tls.key", keyBuf.Bytes(), 0600)
 	require.NoError(t, err, "failed to write key file")
 
 	return certPath, keyPath, parsedCert

tlv/stream.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"errors"
 	"io"
-	"io/ioutil"
 	"math"
 )
 
@@ -262,7 +261,7 @@ func (s *Stream) decode(r io.Reader, parsedTypes TypeMap, p2p bool) (TypeMap,
 			// If the caller provided an initialized TypeMap, record
 			// the encoded bytes.
 			var b *bytes.Buffer
-			writer := ioutil.Discard
+			writer := io.Discard
 			if parsedTypes != nil {
 				b = bytes.NewBuffer(make([]byte, 0, length))
 				writer = b

tor/cmd_onion.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 )
 
@@ -105,7 +104,7 @@ func (f *OnionFile) StorePrivateKey(privateKey []byte) error {
 		privateKeyContent = b.Bytes()
 	}
 
-	err := ioutil.WriteFile(
+	err := os.WriteFile(
 		f.privateKeyPath, privateKeyContent, f.privateKeyPerm,
 	)
 	if err != nil {
@@ -124,7 +123,7 @@ func (f *OnionFile) PrivateKey() ([]byte, error) {
 	}
 
 	// Try to read the Tor private key to pass into the AddOnion call.
-	privateKeyContent, err := ioutil.ReadFile(f.privateKeyPath)
+	privateKeyContent, err := os.ReadFile(f.privateKeyPath)
 	if err != nil {
 		return nil, err
 	}

tor/controller.go

@@ -8,8 +8,8 @@ import (
 	"encoding/hex"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"net/textproto"
+	"os"
 	"regexp"
 	"strconv"
 	"strings"
@@ -597,7 +597,7 @@ func (c *Controller) getAuthCookie(info protocolInfo) ([]byte, error) {
 	cookieFilePath = strings.Trim(cookieFilePath, "\"")
 
 	// Read the cookie from the file and ensure it has the correct length.
-	cookie, err := ioutil.ReadFile(cookieFilePath)
+	cookie, err := os.ReadFile(cookieFilePath)
 	if err != nil {
 		return nil, err
 	}

watchtower/tlv_bench_test.go

@@ -3,7 +3,6 @@ package watchtower_test
 import (
 	"bytes"
 	"io"
-	"io/ioutil"
 	"testing"
 
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
@@ -104,7 +103,7 @@ func BenchmarkEncodeCreateSession(t *testing.B) {
 
 	var err error
 	for i := 0; i < t.N; i++ {
-		err = m.Encode(ioutil.Discard, 0)
+		err = m.Encode(io.Discard, 0)
 	}
 	require.NoError(t, err)
 }
@@ -118,7 +117,7 @@ func BenchmarkEncodeCreateSessionTLV(t *testing.B) {
 
 	var err error
 	for i := 0; i < t.N; i++ {
-		err = m.Encode(ioutil.Discard)
+		err = m.Encode(io.Discard)
 	}
 	require.NoError(t, err)
 }