Replace deprecated `io/ioutil` with `io` and `os` packages (#7212)

The `io/ioutil` package has been deprecated in Go 1.16 (See
https://pkg.go.dev/io/ioutil). This PR replaces the existing `io/ioutil`
functions with their new definitions in `io` and `os` packages.

Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>

CHANGELOG.md

@@ -32,6 +32,7 @@
 * [6415](https://github.com/grafana/loki/pull/6415) **salvacorts**: Evenly spread queriers across kubernetes nodes.
 * [6349](https://github.com/grafana/loki/pull/6349) **simonswine**: Update the default HTTP listen port from 80 to 3100. Make sure to configure the port explicitly if you are using port 80.
 * [6835](https://github.com/grafana/loki/pull/6835) **DylanGuedes**: Add new per-tenant query timeout configuration and remove engine query timeout.
+* [7212](https://github.com/grafana/loki/pull/7212) **Juneezee**: Replaces deprecated `io/ioutil` with `io` and `os`.
 
 #### Promtail
 

clients/cmd/docker-driver/config.go

@@ -3,7 +3,6 @@ package main
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
 	"net/url"
 	"os"
 	"strconv"
@@ -385,7 +384,7 @@ func parseBoolean(key string, logCtx logger.Info, defaultValue bool) (bool, erro
 
 // loadConfig read YAML-formatted config from filename into cfg.
 func loadConfig(filename string, cfg interface{}) error {
-	buf, err := ioutil.ReadFile(filename)
+	buf, err := os.ReadFile(filename)
 	if err != nil {
 		return errors.Wrap(err, "Error reading config file")
 	}

clients/cmd/docker-driver/config_test.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"reflect"
 	"testing"
@@ -82,7 +81,7 @@ var pipeline = PipelineConfig{
 }
 
 func Test_parsePipeline(t *testing.T) {
-	f, err := ioutil.TempFile("/tmp", "Test_parsePipeline")
+	f, err := os.CreateTemp("/tmp", "Test_parsePipeline")
 	if err != nil {
 		t.Fatal(err)
 	}

clients/cmd/fluent-bit/config.go

@@ -4,7 +4,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"strconv"
 	"strings"
 	"time"
@@ -200,7 +200,7 @@ func parseConfig(cfg ConfigGetter) (*config, error) {
 
 	labelMapPath := cfg.Get("LabelMapPath")
 	if labelMapPath != "" {
-		content, err := ioutil.ReadFile(labelMapPath)
+		content, err := os.ReadFile(labelMapPath)
 		if err != nil {
 			return nil, fmt.Errorf("failed to open LabelMap file: %s", err)
 		}

clients/cmd/fluent-bit/config_test.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-	"io/ioutil"
 	"net/url"
 	"os"
 	"reflect"
@@ -229,7 +228,7 @@ func mustParseDuration(u string) time.Duration {
 }
 
 func createTempLabelMap(t *testing.T) string {
-	file, err := ioutil.TempFile("", "labelmap")
+	file, err := os.CreateTemp("", "labelmap")
 	if err != nil {
 		t.Fatal(err)
 	}

clients/pkg/promtail/positions/positions.go

@@ -3,7 +3,6 @@ package positions
 import (
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -215,7 +214,7 @@ func (p *positions) cleanup() {
 
 func readPositionsFile(cfg Config, logger log.Logger) (map[string]string, error) {
 	cleanfn := filepath.Clean(cfg.PositionsFile)
-	buf, err := ioutil.ReadFile(cleanfn)
+	buf, err := os.ReadFile(cleanfn)
 	if err != nil {
 		if os.IsNotExist(err) {
 			return map[string]string{}, nil

clients/pkg/promtail/positions/positions_test.go

@@ -1,7 +1,6 @@
 package positions
 
 import (
-	"io/ioutil"
 	"os"
 	"strings"
 	"testing"
@@ -16,7 +15,7 @@ import (
 func tempFilename(t *testing.T) string {
 	t.Helper()
 
-	temp, err := ioutil.TempFile("", "positions")
+	temp, err := os.CreateTemp("", "positions")
 	if err != nil {
 		t.Fatal("tempFilename:", err)
 	}
@@ -43,7 +42,7 @@ func TestReadPositionsOK(t *testing.T) {
 	yaml := []byte(`positions:
   /tmp/random.log: "17623"
 `)
-	err := ioutil.WriteFile(temp, yaml, 0644)
+	err := os.WriteFile(temp, yaml, 0644)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -63,7 +62,7 @@ func TestReadPositionsEmptyFile(t *testing.T) {
 	}()
 
 	yaml := []byte(``)
-	err := ioutil.WriteFile(temp, yaml, 0644)
+	err := os.WriteFile(temp, yaml, 0644)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -104,7 +103,7 @@ func TestReadPositionsFromBadYaml(t *testing.T) {
 	badYaml := []byte(`positions:
   /tmp/random.log: "176
 `)
-	err := ioutil.WriteFile(temp, badYaml, 0644)
+	err := os.WriteFile(temp, badYaml, 0644)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -126,7 +125,7 @@ func TestReadPositionsFromBadYamlIgnoreCorruption(t *testing.T) {
 	badYaml := []byte(`positions:
   /tmp/random.log: "176
 `)
-	err := ioutil.WriteFile(temp, badYaml, 0644)
+	err := os.WriteFile(temp, badYaml, 0644)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -148,7 +147,7 @@ func Test_ReadOnly(t *testing.T) {
 	yaml := []byte(`positions:
   /tmp/random.log: "17623"
 `)
-	err := ioutil.WriteFile(temp, yaml, 0644)
+	err := os.WriteFile(temp, yaml, 0644)
 	if err != nil {
 		t.Fatal(err)
 	}

clients/pkg/promtail/positions/write_positions_windows.go

@@ -4,7 +4,6 @@
 package positions
 
 import (
-	"io/ioutil"
 	"os"
 	"path/filepath"
 
@@ -24,7 +23,7 @@ func writePositionFile(filename string, positions map[string]string) error {
 	target := filepath.Clean(filename)
 	temp := target + "-new"
 
-	err = ioutil.WriteFile(temp, buf, os.FileMode(positionFileMode))
+	err = os.WriteFile(temp, buf, os.FileMode(positionFileMode))
 	if err != nil {
 		return err
 	}

clients/pkg/promtail/promtail_test.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"math"
 	"math/rand"
 	"net"
@@ -510,7 +509,7 @@ func getPromMetrics(t *testing.T, httpListenAddr net.Addr) ([]byte, string) {
 		t.Fatal("Received a non 200 status code from /metrics endpoint", resp.StatusCode)
 	}
 
-	b, err := ioutil.ReadAll(resp.Body)
+	b, err := io.ReadAll(resp.Body)
 	if err != nil {
 		t.Fatal("Error reading response body from /metrics endpoint", err)
 	}
@@ -656,7 +655,7 @@ func randName() string {
 }
 
 func Test_DryRun(t *testing.T) {
-	f, err := ioutil.TempFile("/tmp", "Test_DryRun")
+	f, err := os.CreateTemp("/tmp", "Test_DryRun")
 	require.NoError(t, err)
 	defer os.Remove(f.Name())
 

clients/pkg/promtail/server/template.go

@@ -3,7 +3,6 @@ package server
 import (
 	"context"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 	"path"
@@ -77,7 +76,7 @@ func getTemplate(name string) (string, error) {
 		defer func() {
 			_ = f.Close()
 		}()
-		b, err := ioutil.ReadAll(f)
+		b, err := io.ReadAll(f)
 		if err != nil {
 			return err
 		}

clients/pkg/promtail/targets/journal/journaltarget.go

@@ -6,7 +6,6 @@ package journal
 import (
 	"fmt"
 	"io"
-	"io/ioutil"
 	"strings"
 	"syscall"
 	"time"
@@ -201,7 +200,7 @@ func journalTargetWithReader(
 
 	go func() {
 		for {
-			err := t.r.Follow(until, ioutil.Discard)
+			err := t.r.Follow(until, io.Discard)
 			if err != nil {
 				level.Error(t.logger).Log("msg", "received error during sdjournal follow", "err", err.Error())
 

clients/pkg/promtail/targets/syslog/syslogtarget_test.go

@@ -5,7 +5,6 @@ import (
 	"crypto/x509"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net"
 	"os"
 	"testing"
@@ -656,7 +655,7 @@ func testSyslogTargetWithTLS(t *testing.T, fmtFunc formatFunc) {
 }
 
 func createTempFile(data []byte) (*os.File, error) {
-	tmpFile, err := ioutil.TempFile("", "")
+	tmpFile, err := os.CreateTemp("", "")
 	if err != nil {
 		return nil, fmt.Errorf("failed to create temporary file: %s", err)
 	}

clients/pkg/promtail/targets/syslog/transport.go

@@ -6,8 +6,8 @@ import (
 	"crypto/x509"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net"
+	"os"
 	"strings"
 	"sync"
 	"time"
@@ -207,7 +207,7 @@ func newTLSConfig(certFile string, keyFile string, caFile string) (*tls.Config,
 	}
 
 	if caFile != "" {
-		caCert, err := ioutil.ReadFile(caFile)
+		caCert, err := os.ReadFile(caFile)
 		if err != nil {
 			return nil, fmt.Errorf("unable to load client CA certificate: %w", err)
 		}

clients/pkg/promtail/targets/windows/bookmark.go

@@ -4,7 +4,7 @@
 package windows
 
 import (
-	"io/ioutil"
+	"io"
 	"os"
 
 	"github.com/spf13/afero"
@@ -52,7 +52,7 @@ func newBookMark(path string) (*bookMark, error) {
 	if err != nil {
 		return nil, err
 	}
-	fileContent, err := ioutil.ReadAll(file)
+	fileContent, err := io.ReadAll(file)
 	if err != nil {
 		return nil, err
 	}

cmd/chunks-inspect/loki.go

@@ -7,7 +7,6 @@ import (
 	"fmt"
 	"hash/crc32"
 	"io"
-	"io/ioutil"
 
 	"github.com/golang/snappy"
 	"github.com/klauspost/compress/flate"
@@ -187,7 +186,7 @@ func parseLokiBlock(compression Encoding, data []byte) ([]byte, []LokiEntry, err
 		return nil, nil, err
 	}
 
-	decompressed, err := ioutil.ReadAll(r)
+	decompressed, err := io.ReadAll(r)
 	origDecompressed := decompressed
 	if err != nil {
 		return nil, nil, err

cmd/chunks-inspect/main.go

@@ -4,7 +4,6 @@ import (
 	"crypto/sha256"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"os"
 	"strings"
@@ -122,7 +121,7 @@ func printFile(filename string, blockDetails, printLines, storeBlocks bool) {
 }
 
 func writeBlockToFile(data []byte, blockIndex int, filename string) {
-	err := ioutil.WriteFile(filename, data, 0644)
+	err := os.WriteFile(filename, data, 0644)
 	if err != nil {
 		log.Println("Failed to store block", blockIndex, "to file", filename, "due to error:", err)
 	} else {

operator/cmd/loki-broker/main.go

@@ -3,7 +3,6 @@ package main
 import (
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path"
 	"strings"
@@ -117,7 +116,7 @@ func main() {
 
 	cfg.validateFlags(logger)
 
-	b, err := ioutil.ReadFile(cfg.crFilepath)
+	b, err := os.ReadFile(cfg.crFilepath)
 	if err != nil {
 		logger.Info("failed to read custom resource file", "path", cfg.crFilepath)
 		os.Exit(1)
@@ -169,7 +168,7 @@ func main() {
 		if cfg.writeToDir != "" {
 			basename := fmt.Sprintf("%s-%s.yaml", o.GetObjectKind().GroupVersionKind().Kind, o.GetName())
 			fname := strings.ToLower(path.Join(cfg.writeToDir, basename))
-			if err := ioutil.WriteFile(fname, b, 0o644); err != nil {
+			if err := os.WriteFile(fname, b, 0o644); err != nil {
 				logger.Error(err, "failed to write file to directory", "path", fname)
 				os.Exit(1)
 			}

operator/controllers/loki/lokistack_controller_test.go

@@ -2,7 +2,7 @@ package controllers
 
 import (
 	"flag"
-	"io/ioutil"
+	"io"
 	"os"
 	"testing"
 
@@ -38,7 +38,7 @@ func TestMain(m *testing.M) {
 	if testing.Verbose() {
 		logger = log.NewLogger("testing", log.WithVerbosity(5))
 	} else {
-		logger = log.NewLogger("testing", log.WithOutput(ioutil.Discard))
+		logger = log.NewLogger("testing", log.WithOutput(io.Discard))
 	}
 
 	// Register the clientgo and CRD schemes

operator/internal/handlers/lokistack_create_or_update_test.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"errors"
 	"flag"
-	"io/ioutil"
+	"io"
 	"os"
 	"testing"
 
@@ -94,7 +94,7 @@ func TestMain(m *testing.M) {
 	if testing.Verbose() {
 		logger = log.NewLogger("testing", log.WithVerbosity(5))
 	} else {
-		logger = log.NewLogger("testing", log.WithOutput(ioutil.Discard))
+		logger = log.NewLogger("testing", log.WithOutput(io.Discard))
 	}
 
 	// Register the clientgo and CRD schemes

operator/internal/manifests/internal/config/build.go

@@ -3,7 +3,7 @@ package config
 import (
 	"bytes"
 	"embed"
-	"io/ioutil"
+	"io"
 	"text/template"
 
 	"github.com/ViaQ/logerr/v2/kverrors"
@@ -38,7 +38,7 @@ func Build(opts Options) ([]byte, []byte, error) {
 	if err != nil {
 		return nil, nil, kverrors.Wrap(err, "failed to create loki configuration")
 	}
-	cfg, err := ioutil.ReadAll(w)
+	cfg, err := io.ReadAll(w)
 	if err != nil {
 		return nil, nil, kverrors.Wrap(err, "failed to read configuration from buffer")
 	}
@@ -48,7 +48,7 @@ func Build(opts Options) ([]byte, []byte, error) {
 	if err != nil {
 		return nil, nil, kverrors.Wrap(err, "failed to create loki runtime configuration")
 	}
-	rcfg, err := ioutil.ReadAll(w)
+	rcfg, err := io.ReadAll(w)
 	if err != nil {
 		return nil, nil, kverrors.Wrap(err, "failed to read configuration from buffer")
 	}

operator/internal/manifests/internal/gateway/build.go

@@ -3,7 +3,7 @@ package gateway
 import (
 	"bytes"
 	"embed"
-	"io/ioutil"
+	"io"
 	"text/template"
 
 	lokiv1 "github.com/grafana/loki/operator/apis/loki/v1"
@@ -47,7 +47,7 @@ func Build(opts Options) (rbacCfg []byte, tenantsCfg []byte, regoCfg []byte, err
 	if err != nil {
 		return nil, nil, nil, kverrors.Wrap(err, "failed to create loki gateway rbac configuration")
 	}
-	rbacCfg, err = ioutil.ReadAll(w)
+	rbacCfg, err = io.ReadAll(w)
 	if err != nil {
 		return nil, nil, nil, kverrors.Wrap(err, "failed to read configuration from buffer")
 	}
@@ -57,7 +57,7 @@ func Build(opts Options) (rbacCfg []byte, tenantsCfg []byte, regoCfg []byte, err
 	if err != nil {
 		return nil, nil, nil, kverrors.Wrap(err, "failed to create loki gateway tenants configuration")
 	}
-	tenantsCfg, err = ioutil.ReadAll(w)
+	tenantsCfg, err = io.ReadAll(w)
 	if err != nil {
 		return nil, nil, nil, kverrors.Wrap(err, "failed to read configuration from buffer")
 	}
@@ -68,7 +68,7 @@ func Build(opts Options) (rbacCfg []byte, tenantsCfg []byte, regoCfg []byte, err
 		if err != nil {
 			return nil, nil, nil, kverrors.Wrap(err, "failed to create lokistack gateway rego configuration")
 		}
-		regoCfg, err = ioutil.ReadAll(w)
+		regoCfg, err = io.ReadAll(w)
 		if err != nil {
 			return nil, nil, nil, kverrors.Wrap(err, "failed to read configuration from buffer")
 		}

pkg/canary/reader/reader.go

@@ -6,7 +6,6 @@ import (
 	"encoding/base64"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"net"
 	"net/http"
@@ -226,7 +225,7 @@ func (r *Reader) QueryCountOverTime(queryRange string) (float64, error) {
 		r.backoffMtx.Lock()
 		r.nextQuery = nextBackoff(r.w, resp.StatusCode, r.backoff)
 		r.backoffMtx.Unlock()
-		buf, _ := ioutil.ReadAll(resp.Body)
+		buf, _ := io.ReadAll(resp.Body)
 		return 0, fmt.Errorf("error response from server: %s (%v)", string(buf), err)
 	}
 	// No Errors, reset backoff
@@ -317,7 +316,7 @@ func (r *Reader) Query(start time.Time, end time.Time) ([]time.Time, error) {
 		r.backoffMtx.Lock()
 		r.nextQuery = nextBackoff(r.w, resp.StatusCode, r.backoff)
 		r.backoffMtx.Unlock()
-		buf, _ := ioutil.ReadAll(resp.Body)
+		buf, _ := io.ReadAll(resp.Body)
 		return nil, fmt.Errorf("error response from server: %s (%v)", string(buf), err)
 	}
 	// No Errors, reset backoff

pkg/distributor/http_test.go

@@ -1,7 +1,7 @@
 package distributor
 
 import (
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -33,7 +33,7 @@ func TestDistributorRingHandler(t *testing.T) {
 		require.NoError(t, err)
 
 		defer resp.Body.Close()
-		body, err := ioutil.ReadAll(resp.Body)
+		body, err := io.ReadAll(resp.Body)
 		require.NoError(t, err)
 		require.Contains(t, string(body), "<th>Instance ID</th>")
 		require.NotContains(t, string(body), "Not running with Global Rating Limit - ring not being used by the Distributor")
@@ -48,7 +48,7 @@ func TestDistributorRingHandler(t *testing.T) {
 		require.NoError(t, err)
 
 		defer resp.Body.Close()
-		body, err := ioutil.ReadAll(resp.Body)
+		body, err := io.ReadAll(resp.Body)
 		require.NoError(t, err)
 		require.Contains(t, string(body), "Not running with Global Rating Limit - ring not being used by the Distributor")
 		require.NotContains(t, string(body), "<th>Instance ID</th>")

pkg/ingester/checkpoint.go

@@ -3,8 +3,7 @@ package ingester
 import (
 	"bytes"
 	"context"
-	fmt "fmt"
-	"io/ioutil"
+	"fmt"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -425,7 +424,7 @@ func checkpointIndex(filename string, includeTmp bool) (int, error) {
 // lastCheckpoint returns the directory name and index of the most recent checkpoint.
 // If dir does not contain any checkpoints, -1 is returned as index.
 func lastCheckpoint(dir string) (string, int, error) {
-	dirs, err := ioutil.ReadDir(dir)
+	dirs, err := os.ReadDir(dir)
 	if err != nil {
 		return "", -1, err
 	}
@@ -466,7 +465,7 @@ func (w *WALCheckpointWriter) deleteCheckpoints(maxIndex int) (err error) {
 
 	errs := tsdb_errors.NewMulti()
 
-	files, err := ioutil.ReadDir(w.segmentWAL.Dir())
+	files, err := os.ReadDir(w.segmentWAL.Dir())
 	if err != nil {
 		return err
 	}

pkg/ingester/checkpoint_test.go

@@ -2,8 +2,8 @@ package ingester
 
 import (
 	"context"
-	fmt "fmt"
-	"io/ioutil"
+	"fmt"
+	"os"
 	"sort"
 	"testing"
 	"time"
@@ -333,7 +333,7 @@ func expectCheckpoint(t *testing.T, walDir string, shouldExist bool, max time.Du
 			<-time.After(max / 10) // check 10x over the duration
 		}
 
-		fs, err := ioutil.ReadDir(walDir)
+		fs, err := os.ReadDir(walDir)
 		require.Nil(t, err)
 		var found bool
 		for _, f := range fs {

pkg/ingester/transfer_test.go

@@ -3,7 +3,6 @@ package ingester
 import (
 	"fmt"
 	"io"
-	"io/ioutil"
 	"sort"
 	"testing"
 	"time"
@@ -143,7 +142,7 @@ func (f *testIngesterFactory) getIngester(joinAfter time.Duration, t *testing.T)
 			PusherClient:   nil,
 			QuerierClient:  nil,
 			IngesterClient: &testIngesterClient{t: f.t, i: ingester},
-			Closer:         ioutil.NopCloser(nil),
+			Closer:         io.NopCloser(nil),
 		}, nil
 	}
 

pkg/logcli/client/client.go

@@ -3,10 +3,11 @@ package client
 import (
 	"encoding/base64"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"log"
 	"net/http"
 	"net/url"
+	"os"
 	"path"
 	"strings"
 	"time"
@@ -221,7 +222,7 @@ func (c *DefaultClient) doRequest(path, query string, quiet bool, out interface{
 			continue
 		}
 		if resp.StatusCode/100 != 2 {
-			buf, _ := ioutil.ReadAll(resp.Body) // nolint
+			buf, _ := io.ReadAll(resp.Body) // nolint
 			log.Printf("Error response from server: %s (%v) attempts remaining: %d", string(buf), err, attempts)
 			if err := resp.Body.Close(); err != nil {
 				log.Println("error closing body", err)
@@ -283,7 +284,7 @@ func (c *DefaultClient) getHTTPRequestHeader() (http.Header, error) {
 	}
 
 	if c.BearerTokenFile != "" {
-		b, err := ioutil.ReadFile(c.BearerTokenFile)
+		b, err := os.ReadFile(c.BearerTokenFile)
 		if err != nil {
 			return nil, fmt.Errorf("unable to read authorization credentials file %s: %s", c.BearerTokenFile, err)
 		}
@@ -335,7 +336,7 @@ func (c *DefaultClient) wsConnect(path, query string, quiet bool) (*websocket.Co
 		if resp == nil {
 			return nil, err
 		}
-		buf, _ := ioutil.ReadAll(resp.Body) // nolint
+		buf, _ := io.ReadAll(resp.Body) // nolint
 		return nil, fmt.Errorf("Error response from server: %s (%v)", string(buf), err)
 	}
 

pkg/logcli/client/file.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"sort"
 	"strings"
 	"time"
@@ -222,7 +221,7 @@ func newFileIterator(
 ) (iter.EntryIterator, error) {
 
 	lr := io.LimitReader(r, defaultMaxFileSize)
-	b, err := ioutil.ReadAll(lr)
+	b, err := io.ReadAll(lr)
 	if err != nil {
 		return nil, err
 	}

pkg/logql/syntax/fuzz_test.go

@@ -4,7 +4,6 @@
 package syntax
 
 import (
-	"io/ioutil"
 	"os"
 	"testing"
 
@@ -15,7 +14,7 @@ const fuzzTestCaseEnvName = "FUZZ_TESTCASE_PATH"
 
 func Test_Fuzz(t *testing.T) {
 	fuzzTestPath := os.Getenv(fuzzTestCaseEnvName)
-	data, err := ioutil.ReadFile(fuzzTestPath)
+	data, err := os.ReadFile(fuzzTestPath)
 	require.NoError(t, err)
 	_, _ = ParseExpr(string(data))
 }

pkg/logqlanalyzer/http.go

@@ -3,7 +3,7 @@ package logqlanalyzer
 import (
 	"context"
 	"encoding/json"
-	"io/ioutil"
+	"io"
 	"net/http"
 
 	"github.com/go-kit/log/level"
@@ -31,7 +31,7 @@ type LogQLAnalyzeHandler struct {
 }
 
 func (s *LogQLAnalyzeHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
-	payload, err := ioutil.ReadAll(req.Body)
+	payload, err := io.ReadAll(req.Body)
 	if err != nil {
 		writeError(req.Context(), w, err, http.StatusBadRequest, "unable to read request body")
 		return

pkg/loki/config_handler_test.go

@@ -1,7 +1,7 @@
 package loki
 
 import (
-	"io/ioutil"
+	"io"
 	"net/http/httptest"
 	"testing"
 
@@ -107,7 +107,7 @@ func TestConfigDiffHandler(t *testing.T) {
 			resp := w.Result()
 			assert.Equal(t, tc.expectedStatusCode, resp.StatusCode)
 
-			body, err := ioutil.ReadAll(resp.Body)
+			body, err := io.ReadAll(resp.Body)
 			assert.NoError(t, err)
 			assert.Equal(t, tc.expectedBody, string(body))
 		})

pkg/loki/config_wrapper_test.go

@@ -3,7 +3,6 @@ package loki
 import (
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"net/url"
 	"os"
 	"reflect"
@@ -39,7 +38,7 @@ func configWrapperFromYAML(t *testing.T, configFileString string, args []string)
 	config := ConfigWrapper{}
 	fs := flag.NewFlagSet(t.Name(), flag.PanicOnError)
 
-	file, err := ioutil.TempFile("", "config.yaml")
+	file, err := os.CreateTemp("", "config.yaml")
 	defer func() {
 		os.Remove(file.Name())
 	}()
@@ -987,7 +986,7 @@ query_range:
 
 func TestDefaultUnmarshal(t *testing.T) {
 	t.Run("with a minimal config file and no command line args, defaults are use", func(t *testing.T) {
-		file, err := ioutil.TempFile("", "config.yaml")
+		file, err := os.CreateTemp("", "config.yaml")
 		defer func() {
 			os.Remove(file.Name())
 		}()

pkg/loki/loki_test.go

@@ -5,7 +5,6 @@ import (
 	"flag"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"strings"
@@ -223,7 +222,7 @@ schema_config:
 
 	defer resp.Body.Close()
 
-	bBytes, err := ioutil.ReadAll(resp.Body)
+	bBytes, err := io.ReadAll(resp.Body)
 	require.NoError(t, err)
 	require.Equal(t, string(bBytes), "abc")
 	assert.True(t, customHandlerInvoked)

pkg/loki/runtime_config_test.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"flag"
 	"io"
-	"io/ioutil"
+	"os"
 	"strings"
 	"testing"
 	"time"
@@ -85,7 +85,7 @@ overrides:
 
 func newTestOverrides(t *testing.T, yaml string) *validation.Overrides {
 	t.Helper()
-	f, err := ioutil.TempFile(t.TempDir(), "bar")
+	f, err := os.CreateTemp(t.TempDir(), "bar")
 	require.NoError(t, err)
 	path := f.Name()
 	// fake loader to load from string instead of file.

pkg/loki/version_handler_test.go

@@ -1,7 +1,7 @@
 package loki
 
 import (
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -35,7 +35,7 @@ func TestVersionHandler(t *testing.T) {
 		"revision":"foobar",
 		"goVersion": "42"
 	}`
-	body, err := ioutil.ReadAll(resp.Body)
+	body, err := io.ReadAll(resp.Body)
 	assert.NoError(t, err)
 	assert.JSONEq(t, expected, string(body))
 }

pkg/lokifrontend/frontend/transport/handler.go

@@ -6,7 +6,6 @@ import (
 	"flag"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 	"strconv"
@@ -123,7 +122,7 @@ func (f *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	// Buffer the body for later use to track slow queries.
 	var buf bytes.Buffer
 	r.Body = http.MaxBytesReader(w, r.Body, f.cfg.MaxBodySize)
-	r.Body = ioutil.NopCloser(io.TeeReader(r.Body, &buf))
+	r.Body = io.NopCloser(io.TeeReader(r.Body, &buf))
 
 	startTime := time.Now()
 	resp, err := f.roundTripper.RoundTrip(r)
@@ -207,7 +206,7 @@ func (f *Handler) reportQueryStats(r *http.Request, queryString url.Values, quer
 
 func (f *Handler) parseRequestQueryString(r *http.Request, bodyBuf bytes.Buffer) url.Values {
 	// Use previously buffered body.
-	r.Body = ioutil.NopCloser(&bodyBuf)
+	r.Body = io.NopCloser(&bodyBuf)
 
 	// Ensure the form has been parsed so all the parameters are present
 	err := r.ParseForm()

pkg/lokifrontend/frontend/transport/roundtripper.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"context"
 	"io"
-	"io/ioutil"
 	"net/http"
 
 	"github.com/weaveworks/common/httpgrpc"
@@ -47,7 +46,7 @@ func (a *grpcRoundTripperAdapter) RoundTrip(r *http.Request) (*http.Response, er
 
 	httpResp := &http.Response{
 		StatusCode:    int(resp.Code),
-		Body:          &buffer{buff: resp.Body, ReadCloser: ioutil.NopCloser(bytes.NewReader(resp.Body))},
+		Body:          &buffer{buff: resp.Body, ReadCloser: io.NopCloser(bytes.NewReader(resp.Body))},
 		Header:        http.Header{},
 		ContentLength: int64(len(resp.Body)),
 	}

pkg/lokifrontend/frontend/v1/frontend_test.go

@@ -3,7 +3,7 @@ package v1
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net"
 	"net/http"
 	"strings"
@@ -55,7 +55,7 @@ func TestFrontend(t *testing.T) {
 		require.NoError(t, err)
 		require.Equal(t, 200, resp.StatusCode)
 
-		body, err := ioutil.ReadAll(resp.Body)
+		body, err := io.ReadAll(resp.Body)
 		require.NoError(t, err)
 
 		assert.Equal(t, "Hello World", string(body))
@@ -105,7 +105,7 @@ func TestFrontendPropagateTrace(t *testing.T) {
 		require.Equal(t, 200, resp.StatusCode)
 
 		defer resp.Body.Close()
-		_, err = ioutil.ReadAll(resp.Body)
+		_, err = io.ReadAll(resp.Body)
 		require.NoError(t, err)
 
 		// Query should do one call.
@@ -201,7 +201,7 @@ func TestFrontendMetricsCleanup(t *testing.T) {
 			require.Equal(t, 200, resp.StatusCode)
 			defer resp.Body.Close()
 
-			body, err := ioutil.ReadAll(resp.Body)
+			body, err := io.ReadAll(resp.Body)
 			require.NoError(t, err)
 
 			assert.Equal(t, "Hello World", string(body))

pkg/querier/queryrange/codec.go

@@ -6,7 +6,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	io "io"
 	"net/http"
 	"net/url"
 	"sort"
@@ -407,7 +407,7 @@ type Buffer interface {
 
 func (Codec) DecodeResponse(ctx context.Context, r *http.Response, req queryrangebase.Request) (queryrangebase.Response, error) {
 	if r.StatusCode/100 != 2 {
-		body, _ := ioutil.ReadAll(r.Body)
+		body, _ := io.ReadAll(r.Body)
 		return nil, httpgrpc.Errorf(r.StatusCode, string(body))
 	}
 
@@ -416,7 +416,7 @@ func (Codec) DecodeResponse(ctx context.Context, r *http.Response, req queryrang
 	if buffer, ok := r.Body.(Buffer); ok {
 		buf = buffer.Bytes()
 	} else {
-		buf, err = ioutil.ReadAll(r.Body)
+		buf, err = io.ReadAll(r.Body)
 		if err != nil {
 			return nil, httpgrpc.Errorf(http.StatusInternalServerError, "error decoding response: %v", err)
 		}
@@ -590,7 +590,7 @@ func (Codec) EncodeResponse(ctx context.Context, res queryrangebase.Response) (*
 		Header: http.Header{
 			"Content-Type": []string{"application/json"},
 		},
-		Body:       ioutil.NopCloser(&buf),
+		Body:       io.NopCloser(&buf),
 		StatusCode: http.StatusOK,
 	}
 	return &resp, nil

pkg/querier/queryrange/codec_test.go

@@ -6,7 +6,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	strings "strings"
 	"testing"
@@ -117,13 +116,13 @@ func Test_codec_DecodeResponse(t *testing.T) {
 		want    queryrangebase.Response
 		wantErr bool
 	}{
-		{"500", &http.Response{StatusCode: 500, Body: ioutil.NopCloser(strings.NewReader("some error"))}, nil, nil, true},
-		{"no body", &http.Response{StatusCode: 200, Body: ioutil.NopCloser(badReader{})}, nil, nil, true},
-		{"bad json", &http.Response{StatusCode: 200, Body: ioutil.NopCloser(strings.NewReader(""))}, nil, nil, true},
-		{"not success", &http.Response{StatusCode: 200, Body: ioutil.NopCloser(strings.NewReader(`{"status":"fail"}`))}, nil, nil, true},
-		{"unknown", &http.Response{StatusCode: 200, Body: ioutil.NopCloser(strings.NewReader(`{"status":"success"}`))}, nil, nil, true},
+		{"500", &http.Response{StatusCode: 500, Body: io.NopCloser(strings.NewReader("some error"))}, nil, nil, true},
+		{"no body", &http.Response{StatusCode: 200, Body: io.NopCloser(badReader{})}, nil, nil, true},
+		{"bad json", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(""))}, nil, nil, true},
+		{"not success", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(`{"status":"fail"}`))}, nil, nil, true},
+		{"unknown", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(`{"status":"success"}`))}, nil, nil, true},
 		{
-			"matrix", &http.Response{StatusCode: 200, Body: ioutil.NopCloser(strings.NewReader(matrixString))}, nil,
+			"matrix", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(matrixString))}, nil,
 			&LokiPromResponse{
 				Response: &queryrangebase.PrometheusResponse{
 					Status: loghttp.QueryStatusSuccess,
@@ -137,7 +136,7 @@ func Test_codec_DecodeResponse(t *testing.T) {
 		},
 		{
 			"matrix-empty-streams",
-			&http.Response{StatusCode: 200, Body: ioutil.NopCloser(strings.NewReader(matrixStringEmptyResult))},
+			&http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(matrixStringEmptyResult))},
 			nil,
 			&LokiPromResponse{
 				Response: &queryrangebase.PrometheusResponse{
@@ -152,7 +151,7 @@ func Test_codec_DecodeResponse(t *testing.T) {
 		},
 		{
 			"vector-empty-streams",
-			&http.Response{StatusCode: 200, Body: ioutil.NopCloser(strings.NewReader(vectorStringEmptyResult))},
+			&http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(vectorStringEmptyResult))},
 			nil,
 			&LokiPromResponse{
 				Response: &queryrangebase.PrometheusResponse{
@@ -166,7 +165,7 @@ func Test_codec_DecodeResponse(t *testing.T) {
 			}, false,
 		},
 		{
-			"streams v1", &http.Response{StatusCode: 200, Body: ioutil.NopCloser(strings.NewReader(streamsString))},
+			"streams v1", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(streamsString))},
 			&LokiRequest{Direction: logproto.FORWARD, Limit: 100, Path: "/loki/api/v1/query_range"},
 			&LokiResponse{
 				Status:    loghttp.QueryStatusSuccess,
@@ -181,7 +180,7 @@ func Test_codec_DecodeResponse(t *testing.T) {
 			}, false,
 		},
 		{
-			"streams legacy", &http.Response{StatusCode: 200, Body: ioutil.NopCloser(strings.NewReader(streamsString))},
+			"streams legacy", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(streamsString))},
 			&LokiRequest{Direction: logproto.FORWARD, Limit: 100, Path: "/api/prom/query_range"},
 			&LokiResponse{
 				Status:    loghttp.QueryStatusSuccess,
@@ -196,7 +195,7 @@ func Test_codec_DecodeResponse(t *testing.T) {
 			}, false,
 		},
 		{
-			"series", &http.Response{StatusCode: 200, Body: ioutil.NopCloser(strings.NewReader(seriesString))},
+			"series", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(seriesString))},
 			&LokiSeriesRequest{Path: "/loki/api/v1/series"},
 			&LokiSeriesResponse{
 				Status:  "success",
@@ -205,7 +204,7 @@ func Test_codec_DecodeResponse(t *testing.T) {
 			}, false,
 		},
 		{
-			"labels legacy", &http.Response{StatusCode: 200, Body: ioutil.NopCloser(strings.NewReader(labelsString))},
+			"labels legacy", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(labelsString))},
 			&LokiLabelNamesRequest{Path: "/api/prom/label"},
 			&LokiLabelNamesResponse{
 				Status:  "success",
@@ -214,7 +213,7 @@ func Test_codec_DecodeResponse(t *testing.T) {
 			}, false,
 		},
 		{
-			"index stats", &http.Response{StatusCode: 200, Body: ioutil.NopCloser(strings.NewReader(indexStatsString))},
+			"index stats", &http.Response{StatusCode: 200, Body: io.NopCloser(strings.NewReader(indexStatsString))},
 			&logproto.IndexStatsRequest{},
 			&IndexStatsResponse{
 				Response: &logproto.IndexStatsResponse{
@@ -456,7 +455,7 @@ func Test_codec_EncodeResponse(t *testing.T) {
 			}
 			if err == nil {
 				require.Equal(t, 200, got.StatusCode)
-				body, err := ioutil.ReadAll(got.Body)
+				body, err := io.ReadAll(got.Body)
 				require.Nil(t, err)
 				bodyString := string(body)
 				require.JSONEq(t, tt.body, bodyString)
@@ -1308,7 +1307,7 @@ func Benchmark_CodecDecodeLogs(b *testing.B) {
 	require.Nil(b, err)
 	reader := bytes.NewReader(buf)
 	resp.Body = &buffer{
-		ReadCloser: ioutil.NopCloser(reader),
+		ReadCloser: io.NopCloser(reader),
 		buff:       buf,
 	}
 	b.ResetTimer()
@@ -1344,7 +1343,7 @@ func Benchmark_CodecDecodeSamples(b *testing.B) {
 	buf, err := io.ReadAll(resp.Body)
 	require.Nil(b, err)
 	reader := bytes.NewReader(buf)
-	resp.Body = ioutil.NopCloser(reader)
+	resp.Body = io.NopCloser(reader)
 	b.ResetTimer()
 	b.ReportAllocs()
 

pkg/querier/queryrange/prometheus.go

@@ -3,7 +3,7 @@ package queryrange
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
+	"io"
 	"net/http"
 
 	jsoniter "github.com/json-iterator/go"
@@ -64,7 +64,7 @@ func (p *LokiPromResponse) encode(ctx context.Context) (*http.Response, error) {
 		Header: http.Header{
 			"Content-Type": []string{"application/json"},
 		},
-		Body:       ioutil.NopCloser(bytes.NewBuffer(b)),
+		Body:       io.NopCloser(bytes.NewBuffer(b)),
 		StatusCode: http.StatusOK,
 	}
 	return &resp, nil

pkg/querier/queryrange/queryrangebase/marshaling_test.go

@@ -3,7 +3,7 @@ package queryrangebase
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
+	"io"
 	"math/rand"
 	"net/http"
 	"testing"
@@ -31,7 +31,7 @@ func BenchmarkPrometheusCodec_DecodeResponse(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		_, err := PrometheusCodec.DecodeResponse(context.Background(), &http.Response{
 			StatusCode:    200,
-			Body:          ioutil.NopCloser(bytes.NewReader(encodedRes)),
+			Body:          io.NopCloser(bytes.NewReader(encodedRes)),
 			ContentLength: int64(len(encodedRes)),
 		}, nil)
 		require.NoError(b, err)

pkg/querier/queryrange/queryrangebase/query_range.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"context"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"math"
 	"net/http"
 	"net/url"
@@ -228,7 +228,7 @@ func (prometheusCodec) EncodeRequest(ctx context.Context, r Request) (*http.Requ
 
 func (prometheusCodec) DecodeResponse(ctx context.Context, r *http.Response, _ Request) (Response, error) {
 	if r.StatusCode/100 != 2 {
-		body, _ := ioutil.ReadAll(r.Body)
+		body, _ := io.ReadAll(r.Body)
 		return nil, httpgrpc.Errorf(r.StatusCode, string(body))
 	}
 	log, ctx := spanlogger.New(ctx, "ParseQueryRangeResponse") //nolint:ineffassign,staticcheck
@@ -297,7 +297,7 @@ func (prometheusCodec) EncodeResponse(ctx context.Context, res Response) (*http.
 		Header: http.Header{
 			"Content-Type": []string{"application/json"},
 		},
-		Body:          ioutil.NopCloser(bytes.NewBuffer(b)),
+		Body:          io.NopCloser(bytes.NewBuffer(b)),
 		StatusCode:    http.StatusOK,
 		ContentLength: int64(len(b)),
 	}

pkg/querier/queryrange/queryrangebase/query_range_test.go

@@ -3,7 +3,7 @@ package queryrangebase
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"strconv"
 	"testing"
@@ -96,7 +96,7 @@ func TestResponse(t *testing.T) {
 			response := &http.Response{
 				StatusCode: 200,
 				Header:     http.Header{"Content-Type": []string{"application/json"}},
-				Body:       ioutil.NopCloser(bytes.NewBuffer([]byte(tc.body))),
+				Body:       io.NopCloser(bytes.NewBuffer([]byte(tc.body))),
 			}
 			resp, err := PrometheusCodec.DecodeResponse(context.Background(), response, nil)
 			require.NoError(t, err)
@@ -106,7 +106,7 @@ func TestResponse(t *testing.T) {
 			response = &http.Response{
 				StatusCode:    200,
 				Header:        http.Header{"Content-Type": []string{"application/json"}},
-				Body:          ioutil.NopCloser(bytes.NewBuffer([]byte(tc.body))),
+				Body:          io.NopCloser(bytes.NewBuffer([]byte(tc.body))),
 				ContentLength: int64(len(tc.body)),
 			}
 			resp2, err := PrometheusCodec.EncodeResponse(context.Background(), resp)

pkg/querier/queryrange/queryrangebase/roundtrip.go

@@ -19,7 +19,6 @@ import (
 	"context"
 	"flag"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"time"
 
@@ -176,7 +175,7 @@ func (q roundTripper) Do(ctx context.Context, r Request) (Response, error) {
 		return nil, err
 	}
 	defer func() {
-		_, _ = io.Copy(ioutil.Discard, io.LimitReader(response.Body, 1024)) //nolint:errcheck
+		_, _ = io.Copy(io.Discard, io.LimitReader(response.Body, 1024)) //nolint:errcheck
 		response.Body.Close()
 	}()
 

pkg/querier/queryrange/roundtrip_test.go

@@ -3,7 +3,7 @@ package queryrange
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
+	"io"
 	"math"
 	"net/http"
 	"net/http/httptest"
@@ -428,7 +428,7 @@ func TestPostQueries(t *testing.T) {
 		"query": {`{app="foo"} |~ "foo"`},
 	}
 	body := bytes.NewBufferString(data.Encode())
-	req.Body = ioutil.NopCloser(body)
+	req.Body = io.NopCloser(body)
 	req.Header.Add("Content-Type", "application/x-www-form-urlencoded")
 	req.Header.Add("Content-Length", strconv.Itoa(len(data.Encode())))
 	req = req.WithContext(user.InjectOrgID(context.Background(), "1"))

pkg/ruler/base/api.go

@@ -2,7 +2,7 @@ package base
 
 import (
 	"encoding/json"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/url"
 	"sort"
@@ -448,7 +448,7 @@ func (a *API) CreateRuleGroup(w http.ResponseWriter, req *http.Request) {
 		return
 	}
 
-	payload, err := ioutil.ReadAll(req.Body)
+	payload, err := io.ReadAll(req.Body)
 	if err != nil {
 		level.Error(logger).Log("msg", "unable to read rule group payload", "err", err.Error())
 		http.Error(w, err.Error(), http.StatusBadRequest)

pkg/ruler/base/api_test.go

@@ -5,7 +5,6 @@ import (
 	"encoding/json"
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"strings"
@@ -33,7 +32,7 @@ func TestRuler_rules(t *testing.T) {
 	a.PrometheusRules(w, req)
 
 	resp := w.Result()
-	body, _ := ioutil.ReadAll(resp.Body)
+	body, _ := io.ReadAll(resp.Body)
 
 	// Check status code and status response
 	responseJSON := response{}
@@ -88,7 +87,7 @@ func TestRuler_rules_special_characters(t *testing.T) {
 	a.PrometheusRules(w, req)
 
 	resp := w.Result()
-	body, _ := ioutil.ReadAll(resp.Body)
+	body, _ := io.ReadAll(resp.Body)
 
 	// Check status code and status response
 	responseJSON := response{}
@@ -143,7 +142,7 @@ func TestRuler_alerts(t *testing.T) {
 	a.PrometheusAlerts(w, req)
 
 	resp := w.Result()
-	body, _ := ioutil.ReadAll(resp.Body)
+	body, _ := io.ReadAll(resp.Body)
 
 	// Check status code and status response
 	responseJSON := response{}

pkg/ruler/base/ruler_test.go

@@ -3,7 +3,7 @@ package base
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"math/rand"
 	"net/http"
 	"net/http/httptest"
@@ -1089,7 +1089,7 @@ func TestRuler_ListAllRules(t *testing.T) {
 	router.ServeHTTP(w, req)
 
 	resp := w.Result()
-	body, _ := ioutil.ReadAll(resp.Body)
+	body, _ := io.ReadAll(resp.Body)
 
 	// Check status code and header
 	require.Equal(t, http.StatusOK, resp.StatusCode)

pkg/ruler/compat.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"context"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"strings"
 	"time"
 
@@ -184,7 +184,7 @@ func (GroupLoader) Parse(query string) (parser.Expr, error) {
 }
 
 func (g GroupLoader) Load(identifier string) (*rulefmt.RuleGroups, []error) {
-	b, err := ioutil.ReadFile(identifier)
+	b, err := os.ReadFile(identifier)
 	if err != nil {
 		return nil, []error{errors.Wrap(err, identifier)}
 	}

pkg/ruler/compat_test.go

@@ -3,7 +3,6 @@ package ruler
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"strings"
 	"testing"
@@ -250,10 +249,10 @@ groups:
 	} {
 		t.Run(tc.desc, func(t *testing.T) {
 			var loader GroupLoader
-			f, err := ioutil.TempFile(os.TempDir(), "rules")
+			f, err := os.CreateTemp(os.TempDir(), "rules")
 			require.Nil(t, err)
 			defer os.Remove(f.Name())
-			err = ioutil.WriteFile(f.Name(), []byte(tc.data), 0777)
+			err = os.WriteFile(f.Name(), []byte(tc.data), 0777)
 			require.Nil(t, err)
 
 			_, errs := loader.Load(f.Name())

pkg/ruler/rulestore/bucketclient/bucket_client.go

@@ -5,7 +5,7 @@ import (
 	"context"
 	"encoding/base64"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"strings"
 
 	"github.com/go-kit/log"
@@ -66,7 +66,7 @@ func (b *BucketRuleStore) getRuleGroup(ctx context.Context, userID, namespace, g
 	}
 	defer func() { _ = reader.Close() }()
 
-	buf, err := ioutil.ReadAll(reader)
+	buf, err := io.ReadAll(reader)
 	if err != nil {
 		return nil, errors.Wrapf(err, "failed to read rule group %s", objectKey)
 	}

pkg/ruler/rulestore/local/local.go

@@ -3,7 +3,6 @@ package local
 import (
 	"context"
 	"flag"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 
@@ -46,25 +45,31 @@ func NewLocalRulesClient(cfg Config, loader promRules.GroupLoader) (*Client, err
 
 func (l *Client) ListAllUsers(ctx context.Context) ([]string, error) {
 	root := l.cfg.Directory
-	infos, err := ioutil.ReadDir(root)
+	dirEntries, err := os.ReadDir(root)
 	if err != nil {
 		return nil, errors.Wrapf(err, "unable to read dir %s", root)
 	}
 
 	var result []string
-	for _, info := range infos {
-		// After resolving link, info.Name() may be different than user, so keep original name.
-		user := info.Name()
+	for _, entry := range dirEntries {
+		// After resolving link, entry.Name() may be different than user, so keep original name.
+		user := entry.Name()
 
-		if info.Mode()&os.ModeSymlink != 0 {
-			// ioutil.ReadDir only returns result of LStat. Calling Stat resolves symlink.
-			info, err = os.Stat(filepath.Join(root, info.Name()))
+		var isDir bool
+
+		if entry.Type()&os.ModeSymlink != 0 {
+			// os.ReadDir only returns result of LStat. Calling Stat resolves symlink.
+			fi, err := os.Stat(filepath.Join(root, entry.Name()))
 			if err != nil {
 				return nil, err
 			}
+
+			isDir = fi.IsDir()
+		} else {
+			isDir = entry.IsDir()
 		}
 
-		if info.IsDir() {
+		if isDir {
 			result = append(result, user)
 		}
 	}
@@ -130,25 +135,30 @@ func (l *Client) loadAllRulesGroupsForUser(ctx context.Context, userID string) (
 	var allLists rulespb.RuleGroupList
 
 	root := filepath.Join(l.cfg.Directory, userID)
-	infos, err := ioutil.ReadDir(root)
+	dirEntries, err := os.ReadDir(root)
 	if err != nil {
 		return nil, errors.Wrapf(err, "unable to read rule dir %s", root)
 	}
 
-	for _, info := range infos {
-		// After resolving link, info.Name() may be different than namespace, so keep original name.
-		namespace := info.Name()
+	for _, entry := range dirEntries {
+		// After resolving link, entry.Name() may be different than namespace, so keep original name.
+		namespace := entry.Name()
+
+		var isDir bool
 
-		if info.Mode()&os.ModeSymlink != 0 {
-			// ioutil.ReadDir only returns result of LStat. Calling Stat resolves symlink.
-			path := filepath.Join(root, info.Name())
-			info, err = os.Stat(path)
+		if entry.Type()&os.ModeSymlink != 0 {
+			// os.ReadDir only returns result of LStat. Calling Stat resolves symlink.
+			path := filepath.Join(root, entry.Name())
+			fi, err := os.Stat(path)
 			if err != nil {
 				return nil, errors.Wrapf(err, "unable to stat rule file %s", path)
 			}
+			isDir = fi.IsDir()
+		} else {
+			isDir = entry.IsDir()
 		}
 
-		if info.IsDir() {
+		if isDir {
 			continue
 		}
 

pkg/ruler/rulestore/local/local_test.go

@@ -2,7 +2,6 @@ package local
 
 import (
 	"context"
-	"io/ioutil"
 	"os"
 	"path"
 	"testing"
@@ -51,7 +50,7 @@ func TestClient_LoadAllRuleGroups(t *testing.T) {
 	err = os.Symlink(user1, path.Join(dir, user2))
 	require.NoError(t, err)
 
-	err = ioutil.WriteFile(path.Join(dir, user1, namespace1), b, 0777)
+	err = os.WriteFile(path.Join(dir, user1, namespace1), b, 0777)
 	require.NoError(t, err)
 
 	const ignoredDir = "ignored-dir"

pkg/ruler/rulestore/objectclient/rule_store.go

@@ -5,7 +5,7 @@ import (
 	"context"
 	"encoding/base64"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"strings"
 
 	"github.com/go-kit/log"
@@ -63,7 +63,7 @@ func (o *RuleStore) getRuleGroup(ctx context.Context, objectKey string, rg *rule
 	}
 	defer func() { _ = reader.Close() }()
 
-	buf, err := ioutil.ReadAll(reader)
+	buf, err := io.ReadAll(reader)
 	if err != nil {
 		return nil, errors.Wrapf(err, "failed to read rule group %s", objectKey)
 	}

pkg/storage/chunk/client/aws/mock.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"context"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"sort"
 	"strings"
 	"sync"
@@ -404,7 +404,7 @@ func (m *mockS3) PutObjectWithContext(_ aws.Context, req *s3.PutObjectInput, _ .
 	m.Lock()
 	defer m.Unlock()
 
-	buf, err := ioutil.ReadAll(req.Body)
+	buf, err := io.ReadAll(req.Body)
 	if err != nil {
 		return nil, err
 	}
@@ -423,6 +423,6 @@ func (m *mockS3) GetObjectWithContext(_ aws.Context, req *s3.GetObjectInput, _ .
 	}
 
 	return &s3.GetObjectOutput{
-		Body: ioutil.NopCloser(bytes.NewReader(buf)),
+		Body: io.NopCloser(bytes.NewReader(buf)),
 	}, nil
 }

pkg/storage/chunk/client/cassandra/storage_client.go

@@ -6,7 +6,7 @@ import (
 	"crypto/tls"
 	"flag"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"strings"
 	"time"
 
@@ -202,7 +202,7 @@ func (cfg *Config) setClusterConfig(cluster *gocql.ClusterConfig) error {
 	if cfg.Auth {
 		password := cfg.Password.String()
 		if cfg.PasswordFile != "" {
-			passwordBytes, err := ioutil.ReadFile(cfg.PasswordFile)
+			passwordBytes, err := os.ReadFile(cfg.PasswordFile)
 			if err != nil {
 				return errors.Errorf("Could not read Cassandra password file: %v", err)
 			}

pkg/storage/chunk/client/local/fixtures.go

@@ -2,7 +2,6 @@ package local
 
 import (
 	"io"
-	"io/ioutil"
 	"os"
 	"time"
 
@@ -27,7 +26,7 @@ func (f *fixture) Clients() (
 	indexClient index.Client, chunkClient client.Client, tableClient index.TableClient,
 	schemaConfig config.SchemaConfig, closer io.Closer, err error,
 ) {
-	f.dirname, err = ioutil.TempDir(os.TempDir(), "boltdb")
+	f.dirname, err = os.MkdirTemp(os.TempDir(), "boltdb")
 	if err != nil {
 		return
 	}

pkg/storage/chunk/client/local/fs_object_client_test.go

@@ -3,7 +3,6 @@ package local
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
 	"os"
 	"path"
 	"path/filepath"
@@ -41,12 +40,12 @@ func TestFSObjectClient_DeleteChunksBefore(t *testing.T) {
 	require.NoError(t, f.Close())
 
 	// Verify whether all files are created
-	files, _ := ioutil.ReadDir(".")
+	files, _ := os.ReadDir(".")
 	require.Equal(t, 2, len(files), "Number of files should be 2")
 
 	// No files should be deleted, since all of them are not much older
 	require.NoError(t, bucketClient.DeleteChunksBefore(context.Background(), time.Now().Add(-deleteFilesOlderThan)))
-	files, _ = ioutil.ReadDir(".")
+	files, _ = os.ReadDir(".")
 	require.Equal(t, 2, len(files), "Number of files should be 2")
 
 	// Changing mtime of file1 to make it look older
@@ -54,7 +53,7 @@ func TestFSObjectClient_DeleteChunksBefore(t *testing.T) {
 	require.NoError(t, bucketClient.DeleteChunksBefore(context.Background(), time.Now().Add(-deleteFilesOlderThan)))
 
 	// Verifying whether older file got deleted
-	files, _ = ioutil.ReadDir(".")
+	files, _ = os.ReadDir(".")
 	require.Equal(t, 1, len(files), "Number of files should be 1 after enforcing retention")
 }
 

pkg/storage/chunk/client/openstack/swift_object_client.go

@@ -6,7 +6,6 @@ import (
 	"flag"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"time"
 
@@ -132,7 +131,7 @@ func (s *SwiftObjectClient) GetObject(ctx context.Context, objectKey string) (io
 		return nil, 0, err
 	}
 
-	return ioutil.NopCloser(&buf), int64(buf.Len()), nil
+	return io.NopCloser(&buf), int64(buf.Len()), nil
 }
 
 // PutObject puts the specified bytes into the configured Swift container at the provided key

pkg/storage/chunk/client/testutils/inmemory_storage_client.go

@@ -6,7 +6,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"sort"
 	"strings"
 	"sync"
@@ -435,11 +434,11 @@ func (m *MockStorage) GetObject(ctx context.Context, objectKey string) (io.ReadC
 		return nil, 0, errStorageObjectNotFound
 	}
 
-	return ioutil.NopCloser(bytes.NewReader(buf)), int64(len(buf)), nil
+	return io.NopCloser(bytes.NewReader(buf)), int64(len(buf)), nil
 }
 
 func (m *MockStorage) PutObject(ctx context.Context, objectKey string, object io.ReadSeeker) error {
-	buf, err := ioutil.ReadAll(object)
+	buf, err := io.ReadAll(object)
 	if err != nil {
 		return err
 	}

pkg/storage/stores/indexshipper/compactor/compactor_test.go

@@ -3,7 +3,7 @@ package compactor
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"strings"
 	"testing"
@@ -139,7 +139,7 @@ func TestCompactor_RunCompaction(t *testing.T) {
 	for i := tableNumStart; i <= tableNumEnd; i++ {
 		name := fmt.Sprintf("%s%d", indexTablePrefix, i)
 		// verify that we have only 1 file left in storage after compaction.
-		files, err := ioutil.ReadDir(filepath.Join(tablesPath, name))
+		files, err := os.ReadDir(filepath.Join(tablesPath, name))
 		require.NoError(t, err)
 		require.Len(t, files, 1)
 		require.True(t, strings.HasSuffix(files[0].Name(), ".gz"))

pkg/storage/stores/indexshipper/compactor/deletion/delete_requests_client.go

@@ -5,7 +5,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 	"sync"
@@ -167,7 +166,7 @@ func (c *deleteRequestsClient) getRequestsFromServer(ctx context.Context, userID
 		return nil, err
 	}
 	defer func() {
-		_, _ = io.Copy(ioutil.Discard, resp.Body)
+		_, _ = io.Copy(io.Discard, resp.Body)
 		_ = resp.Body.Close()
 	}()
 

pkg/storage/stores/indexshipper/compactor/retention/marker.go

@@ -5,7 +5,6 @@ import (
 	"encoding/binary"
 	"fmt"
 	"io/fs"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"sort"
@@ -253,7 +252,7 @@ func (r *markerProcessor) processPath(path string, deleteFunc func(ctx context.C
 		queue = make(chan *keyPair)
 	)
 	// we use a copy to view the file so that we can read and update at the same time.
-	viewFile, err := ioutil.TempFile("/tmp/", "marker-view-")
+	viewFile, err := os.CreateTemp("/tmp/", "marker-view-")
 	if err != nil {
 		return err
 	}

pkg/storage/stores/indexshipper/compactor/table_test.go

@@ -3,7 +3,6 @@ package compactor
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -303,7 +302,7 @@ func TestTable_CompactionRetention(t *testing.T) {
 			"emptied table": {
 				dbsSetup: setup,
 				assert: func(t *testing.T, storagePath, tableName string) {
-					_, err := ioutil.ReadDir(filepath.Join(storagePath, tableName))
+					_, err := os.ReadDir(filepath.Join(storagePath, tableName))
 					require.True(t, os.IsNotExist(err))
 				},
 				tableMarker: TableMarkerFunc(func(ctx context.Context, tableName, userID string, indexFile retention.IndexProcessor, logger log.Logger) (bool, bool, error) {
@@ -411,14 +410,14 @@ func validateTable(t *testing.T, path string, expectedNumCommonDBs, numUsers int
 }
 
 func listDir(t *testing.T, path string) (files, folders []string) {
-	filesInfo, err := ioutil.ReadDir(path)
+	dirEntries, err := os.ReadDir(path)
 	require.NoError(t, err)
 
-	for _, fileInfo := range filesInfo {
-		if fileInfo.IsDir() {
-			folders = append(folders, fileInfo.Name())
+	for _, entry := range dirEntries {
+		if entry.IsDir() {
+			folders = append(folders, entry.Name())
 		} else {
-			files = append(files, fileInfo.Name())
+			files = append(files, entry.Name())
 		}
 	}
 
@@ -446,7 +445,7 @@ func TestTable_CompactionFailure(t *testing.T) {
 	SetupTable(t, filepath.Join(objectStoragePath, tableName), IndexesConfig{NumCompactedFiles: numDBs}, PerUserIndexesConfig{})
 
 	// put a corrupt zip file in the table which should cause the compaction to fail in the middle because it would fail to open that file with boltdb client.
-	require.NoError(t, ioutil.WriteFile(filepath.Join(tablePathInStorage, "fail.gz"), []byte("fail the compaction"), 0o666))
+	require.NoError(t, os.WriteFile(filepath.Join(tablePathInStorage, "fail.gz"), []byte("fail the compaction"), 0o666))
 
 	// do the compaction
 	objectClient, err := local.NewFSObjectClient(local.FSConfig{Directory: objectStoragePath})
@@ -460,7 +459,7 @@ func TestTable_CompactionFailure(t *testing.T) {
 	require.Error(t, table.compact(false))
 
 	// ensure that files in storage are intact.
-	files, err := ioutil.ReadDir(tablePathInStorage)
+	files, err := os.ReadDir(tablePathInStorage)
 	require.NoError(t, err)
 	require.Len(t, files, numDBs+1)
 

pkg/storage/stores/indexshipper/compactor/testutil.go

@@ -5,7 +5,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"sort"
@@ -82,7 +81,7 @@ func SetupTable(t *testing.T, path string, commonDBsConfig IndexesConfig, perUse
 	idx := 0
 	for filename, content := range commonIndexes {
 		filePath := filepath.Join(path, strings.TrimSuffix(filename, ".gz"))
-		require.NoError(t, ioutil.WriteFile(filePath, []byte(content), 0777))
+		require.NoError(t, os.WriteFile(filePath, []byte(content), 0777))
 		if strings.HasSuffix(filename, ".gz") {
 			compressFile(t, filePath)
 		}
@@ -93,7 +92,7 @@ func SetupTable(t *testing.T, path string, commonDBsConfig IndexesConfig, perUse
 		require.NoError(t, util.EnsureDirectory(filepath.Join(path, userID)))
 		for filename, content := range files {
 			filePath := filepath.Join(path, userID, strings.TrimSuffix(filename, ".gz"))
-			require.NoError(t, ioutil.WriteFile(filePath, []byte(content), 0777))
+			require.NoError(t, os.WriteFile(filePath, []byte(content), 0777))
 			if strings.HasSuffix(filename, ".gz") {
 				compressFile(t, filePath)
 			}
@@ -349,15 +348,15 @@ func (i testIndexCompactor) OpenCompactedIndexFile(_ context.Context, path, _, _
 
 func verifyCompactedIndexTable(t *testing.T, commonDBsConfig IndexesConfig, perUserDBsConfig PerUserIndexesConfig, tablePathInStorage string) {
 	commonIndexes, perUserIndexes := buildFilesContent(commonDBsConfig, perUserDBsConfig)
-	filesInfo, err := ioutil.ReadDir(tablePathInStorage)
+	dirEntries, err := os.ReadDir(tablePathInStorage)
 	require.NoError(t, err)
 
 	files, folders := []string{}, []string{}
-	for _, fileInfo := range filesInfo {
-		if fileInfo.IsDir() {
-			folders = append(folders, fileInfo.Name())
+	for _, entry := range dirEntries {
+		if entry.IsDir() {
+			folders = append(folders, entry.Name())
 		} else {
-			files = append(files, fileInfo.Name())
+			files = append(files, entry.Name())
 		}
 	}
 
@@ -401,12 +400,12 @@ func verifyCompactedIndexTable(t *testing.T, commonDBsConfig IndexesConfig, perU
 
 	require.Len(t, folders, len(expectedUserIndexContent), fmt.Sprintf("%v", commonIndexes))
 	for _, userID := range folders {
-		filesInfo, err := ioutil.ReadDir(filepath.Join(tablePathInStorage, userID))
+		entries, err := os.ReadDir(filepath.Join(tablePathInStorage, userID))
 		require.NoError(t, err)
-		require.Len(t, filesInfo, 1)
-		require.False(t, filesInfo[0].IsDir())
+		require.Len(t, entries, 1)
+		require.False(t, entries[0].IsDir())
 		sort.Strings(expectedUserIndexContent[userID])
-		require.Equal(t, strings.Join(expectedUserIndexContent[userID], ""), string(readFile(t, filepath.Join(tablePathInStorage, userID, filesInfo[0].Name()))))
+		require.Equal(t, strings.Join(expectedUserIndexContent[userID], ""), string(readFile(t, filepath.Join(tablePathInStorage, userID, entries[0].Name()))))
 	}
 }
 
@@ -418,7 +417,7 @@ func readFile(t *testing.T, path string) []byte {
 		path = decompressedFilePath
 	}
 
-	fileContent, err := ioutil.ReadFile(path)
+	fileContent, err := os.ReadFile(path)
 	require.NoError(t, err)
 
 	return fileContent

pkg/storage/stores/indexshipper/downloads/index_set.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -113,18 +112,18 @@ func (t *indexSet) Init(forQuerying bool) (err error) {
 		t.indexMtx.markReady()
 	}()
 
-	filesInfo, err := ioutil.ReadDir(t.cacheLocation)
+	dirEntries, err := os.ReadDir(t.cacheLocation)
 	if err != nil {
 		return err
 	}
 
 	// open all the locally present files first to avoid downloading them again during sync operation below.
-	for _, fileInfo := range filesInfo {
-		if fileInfo.IsDir() {
+	for _, entry := range dirEntries {
+		if entry.IsDir() {
 			continue
 		}
 
-		fullPath := filepath.Join(t.cacheLocation, fileInfo.Name())
+		fullPath := filepath.Join(t.cacheLocation, entry.Name())
 		// if we fail to open an index file, lets skip it and let sync operation re-download the file from storage.
 		idx, err := t.openIndexFileFunc(fullPath)
 		if err != nil {
@@ -138,7 +137,7 @@ func (t *indexSet) Init(forQuerying bool) (err error) {
 			continue
 		}
 
-		t.index[fileInfo.Name()] = idx
+		t.index[entry.Name()] = idx
 	}
 
 	level.Debug(logger).Log("msg", fmt.Sprintf("opened %d local files, now starting sync operation", len(t.index)))

pkg/storage/stores/indexshipper/downloads/index_set_test.go

@@ -3,7 +3,6 @@ package downloads
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"testing"
@@ -135,14 +134,14 @@ func TestIndexSet_Sync(t *testing.T) {
 
 	// first, let us add a new file and refresh the index list cache
 	oneMoreDB := "one-more-db"
-	require.NoError(t, ioutil.WriteFile(filepath.Join(tablePathInStorage, oneMoreDB), []byte(oneMoreDB), 0755))
+	require.NoError(t, os.WriteFile(filepath.Join(tablePathInStorage, oneMoreDB), []byte(oneMoreDB), 0755))
 	indexSet.baseIndexSet.RefreshIndexListCache(context.Background())
 
 	// now, without syncing the indexset, let us compact the index in storage
 	compactedDBName := "compacted-db"
 	require.NoError(t, os.RemoveAll(tablePathInStorage))
 	require.NoError(t, util.EnsureDirectory(tablePathInStorage))
-	require.NoError(t, ioutil.WriteFile(filepath.Join(tablePathInStorage, compactedDBName), []byte(compactedDBName), 0755))
+	require.NoError(t, os.WriteFile(filepath.Join(tablePathInStorage, compactedDBName), []byte(compactedDBName), 0755))
 	indexesSetup = []string{compactedDBName}
 
 	// verify that we are getting errIndexListCacheTooStale without refreshing the list cache

pkg/storage/stores/indexshipper/downloads/table.go

@@ -3,7 +3,7 @@ package downloads
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"sync"
 	"time"
@@ -76,7 +76,7 @@ func LoadTable(name, cacheLocation string, storageClient storage.Client, openInd
 		return nil, err
 	}
 
-	filesInfo, err := ioutil.ReadDir(cacheLocation)
+	dirEntries, err := os.ReadDir(cacheLocation)
 	if err != nil {
 		return nil, err
 	}
@@ -93,15 +93,15 @@ func LoadTable(name, cacheLocation string, storageClient storage.Client, openInd
 		metrics:            metrics,
 	}
 
-	level.Debug(table.logger).Log("msg", fmt.Sprintf("opening locally present files for table %s", name), "files", fmt.Sprint(filesInfo))
+	level.Debug(table.logger).Log("msg", fmt.Sprintf("opening locally present files for table %s", name), "files", fmt.Sprint(dirEntries))
 
 	// common index files are outside the directories and user index files are in the directories
-	for _, fileInfo := range filesInfo {
-		if !fileInfo.IsDir() {
+	for _, entry := range dirEntries {
+		if !entry.IsDir() {
 			continue
 		}
 
-		userID := fileInfo.Name()
+		userID := entry.Name()
 		userIndexSet, err := NewIndexSet(name, userID, filepath.Join(cacheLocation, userID),
 			table.baseUserIndexSet, openIndexFileFunc, loggerWithUserID(table.logger, userID))
 		if err != nil {

pkg/storage/stores/indexshipper/downloads/table_manager.go

@@ -3,7 +3,7 @@ package downloads
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"regexp"
 	"strconv"
@@ -373,33 +373,33 @@ func (tm *tableManager) findUsersInTableForQueryReadiness(tableNumber int64, use
 
 // loadLocalTables loads tables present locally.
 func (tm *tableManager) loadLocalTables() error {
-	filesInfo, err := ioutil.ReadDir(tm.cfg.CacheDir)
+	dirEntries, err := os.ReadDir(tm.cfg.CacheDir)
 	if err != nil {
 		return err
 	}
 
-	for _, fileInfo := range filesInfo {
-		if !fileInfo.IsDir() {
+	for _, entry := range dirEntries {
+		if !entry.IsDir() {
 			continue
 		}
 
-		tableNumber, err := extractTableNumberFromName(fileInfo.Name())
+		tableNumber, err := extractTableNumberFromName(entry.Name())
 		if err != nil {
 			return err
 		}
-		if tableNumber == -1 || !tm.tableRangesToHandle.TableInRange(tableNumber, fileInfo.Name()) {
+		if tableNumber == -1 || !tm.tableRangesToHandle.TableInRange(tableNumber, entry.Name()) {
 			continue
 		}
 
-		level.Info(util_log.Logger).Log("msg", fmt.Sprintf("loading local table %s", fileInfo.Name()))
+		level.Info(util_log.Logger).Log("msg", fmt.Sprintf("loading local table %s", entry.Name()))
 
-		table, err := LoadTable(fileInfo.Name(), filepath.Join(tm.cfg.CacheDir, fileInfo.Name()),
+		table, err := LoadTable(entry.Name(), filepath.Join(tm.cfg.CacheDir, entry.Name()),
 			tm.indexStorageClient, tm.openIndexFileFunc, tm.metrics)
 		if err != nil {
 			return err
 		}
 
-		tm.tables[fileInfo.Name()] = table
+		tm.tables[entry.Name()] = table
 	}
 
 	return nil

pkg/storage/stores/indexshipper/downloads/table_test.go

@@ -2,7 +2,7 @@ package downloads
 
 import (
 	"context"
-	"io/ioutil"
+	"io"
 	"os"
 	"path/filepath"
 	"sort"
@@ -301,8 +301,8 @@ func TestTable_Sync(t *testing.T) {
 	newDB := "new"
 
 	require.NoError(t, os.MkdirAll(tablePathInStorage, 0755))
-	require.NoError(t, ioutil.WriteFile(filepath.Join(tablePathInStorage, deleteDB), []byte(deleteDB), 0755))
-	require.NoError(t, ioutil.WriteFile(filepath.Join(tablePathInStorage, noUpdatesDB), []byte(noUpdatesDB), 0755))
+	require.NoError(t, os.WriteFile(filepath.Join(tablePathInStorage, deleteDB), []byte(deleteDB), 0755))
+	require.NoError(t, os.WriteFile(filepath.Join(tablePathInStorage, noUpdatesDB), []byte(noUpdatesDB), 0755))
 
 	// create table instance
 	table, stopFunc := buildTestTable(t, tempDir)
@@ -326,7 +326,7 @@ func TestTable_Sync(t *testing.T) {
 
 	// remove deleteDB and add the newDB
 	require.NoError(t, os.Remove(filepath.Join(tablePathInStorage, deleteDB)))
-	require.NoError(t, ioutil.WriteFile(filepath.Join(tablePathInStorage, newDB), []byte(newDB), 0755))
+	require.NoError(t, os.WriteFile(filepath.Join(tablePathInStorage, newDB), []byte(newDB), 0755))
 
 	// sync the table
 	table.storageClient.RefreshIndexListCache(context.Background())
@@ -347,13 +347,13 @@ func TestTable_Sync(t *testing.T) {
 		noUpdatesDB: {},
 		newDB:       {},
 	}
-	filesInfo, err := ioutil.ReadDir(tablePathInStorage)
+	dirEntries, err := os.ReadDir(tablePathInStorage)
 	require.NoError(t, err)
 	require.Len(t, table.indexSets[""].(*indexSet).index, len(expectedFilesInDir))
 
-	for _, fileInfo := range filesInfo {
-		require.False(t, fileInfo.IsDir())
-		_, ok := expectedFilesInDir[fileInfo.Name()]
+	for _, entry := range dirEntries {
+		require.False(t, entry.IsDir())
+		_, ok := expectedFilesInDir[entry.Name()]
 		require.True(t, ok)
 	}
 
@@ -361,12 +361,12 @@ func TestTable_Sync(t *testing.T) {
 
 	// first, let us add a new file and refresh the index list cache
 	oneMoreDB := "one-more-db"
-	require.NoError(t, ioutil.WriteFile(filepath.Join(tablePathInStorage, oneMoreDB), []byte(oneMoreDB), 0755))
+	require.NoError(t, os.WriteFile(filepath.Join(tablePathInStorage, oneMoreDB), []byte(oneMoreDB), 0755))
 	table.storageClient.RefreshIndexListCache(context.Background())
 
 	// now, without syncing the table, let us compact the index in storage
 	compactedDBName := "compacted-db"
-	require.NoError(t, ioutil.WriteFile(filepath.Join(tablePathInStorage, compactedDBName), []byte(compactedDBName), 0755))
+	require.NoError(t, os.WriteFile(filepath.Join(tablePathInStorage, compactedDBName), []byte(compactedDBName), 0755))
 	require.NoError(t, os.Remove(filepath.Join(tablePathInStorage, noUpdatesDB)))
 	require.NoError(t, os.Remove(filepath.Join(tablePathInStorage, newDB)))
 	require.NoError(t, os.Remove(filepath.Join(tablePathInStorage, oneMoreDB)))
@@ -461,7 +461,7 @@ func verifyIndexForEach(t *testing.T, expectedIndexes []string, forEachFunc func
 		require.NoError(t, err)
 
 		// read the contents of the index.
-		buf, err := ioutil.ReadAll(readSeeker)
+		buf, err := io.ReadAll(readSeeker)
 		require.NoError(t, err)
 
 		// see if it matches the name of the file

pkg/storage/stores/indexshipper/downloads/testutil.go

@@ -2,7 +2,6 @@ package downloads
 
 import (
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -40,7 +39,7 @@ func setupIndexesAtPath(t *testing.T, userID, path string, start, end int) []str
 		fileName := buildIndexFilename(userID, start)
 		indexPath := filepath.Join(path, fileName)
 
-		require.NoError(t, ioutil.WriteFile(indexPath, []byte(fileName), 0755))
+		require.NoError(t, os.WriteFile(indexPath, []byte(fileName), 0755))
 		testIndexes = append(testIndexes, indexPath)
 	}
 

pkg/storage/stores/indexshipper/storage/client_test.go

@@ -3,7 +3,8 @@ package storage
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
+	"io"
+	"os"
 	"path/filepath"
 	"testing"
 
@@ -28,7 +29,7 @@ func TestIndexStorageClient(t *testing.T) {
 	for tableName, files := range tablesToSetup {
 		require.NoError(t, util.EnsureDirectory(filepath.Join(tempDir, storageKeyPrefix, tableName)))
 		for _, file := range files {
-			err := ioutil.WriteFile(filepath.Join(tempDir, storageKeyPrefix, tableName, file), []byte(tableName+file), 0o666)
+			err := os.WriteFile(filepath.Join(tempDir, storageKeyPrefix, tableName, file), []byte(tableName+file), 0o666)
 			require.NoError(t, err)
 		}
 	}
@@ -53,7 +54,7 @@ func TestIndexStorageClient(t *testing.T) {
 				readCloser, err := indexStorageClient.GetFile(context.Background(), table, fileInStorage.Name)
 				require.NoError(t, err)
 
-				b, err := ioutil.ReadAll(readCloser)
+				b, err := io.ReadAll(readCloser)
 				require.NoError(t, readCloser.Close())
 				require.NoError(t, err)
 				require.EqualValues(t, []byte(table+fileInStorage.Name), b)

pkg/storage/stores/indexshipper/storage/util_test.go

@@ -3,7 +3,6 @@ package storage
 import (
 	"context"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"testing"
@@ -23,7 +22,7 @@ func Test_GetFileFromStorage(t *testing.T) {
 	testData := []byte("test-data")
 	tableName := "test-table"
 	require.NoError(t, util.EnsureDirectory(filepath.Join(tempDir, tableName)))
-	require.NoError(t, ioutil.WriteFile(filepath.Join(tempDir, tableName, "src"), testData, 0o666))
+	require.NoError(t, os.WriteFile(filepath.Join(tempDir, tableName, "src"), testData, 0o666))
 
 	// try downloading the file from the storage.
 	objectClient, err := local.NewFSObjectClient(local.FSConfig{Directory: tempDir})
@@ -37,7 +36,7 @@ func Test_GetFileFromStorage(t *testing.T) {
 		}))
 
 	// verify the contents of the downloaded file.
-	b, err := ioutil.ReadFile(filepath.Join(tempDir, "dest"))
+	b, err := os.ReadFile(filepath.Join(tempDir, "dest"))
 	require.NoError(t, err)
 
 	require.Equal(t, testData, b)
@@ -52,7 +51,7 @@ func Test_GetFileFromStorage(t *testing.T) {
 		}))
 
 	// verify the contents of the downloaded gz file.
-	b, err = ioutil.ReadFile(filepath.Join(tempDir, "dest.gz"))
+	b, err = os.ReadFile(filepath.Join(tempDir, "dest.gz"))
 	require.NoError(t, err)
 
 	require.Equal(t, testData, b)

pkg/storage/stores/indexshipper/uploads/index_set_test.go

@@ -2,7 +2,8 @@ package uploads
 
 import (
 	"context"
-	"io/ioutil"
+	"io"
+	"os"
 	"path/filepath"
 	"testing"
 	"time"
@@ -72,7 +73,7 @@ func TestIndexSet_Upload(t *testing.T) {
 				// compare the contents of created test index and uploaded index in storage
 				_, err = testIndex.Seek(0, 0)
 				require.NoError(t, err)
-				expectedIndexContent, err := ioutil.ReadAll(testIndex.File)
+				expectedIndexContent, err := io.ReadAll(testIndex.File)
 				require.NoError(t, err)
 				require.Equal(t, expectedIndexContent, readCompressedFile(t, indexPathInStorage))
 			}
@@ -156,7 +157,7 @@ func readCompressedFile(t *testing.T, path string) []byte {
 	decompressedFilePath := filepath.Join(tempDir, "decompressed")
 	testutil.DecompressFile(t, path, decompressedFilePath)
 
-	fileContent, err := ioutil.ReadFile(decompressedFilePath)
+	fileContent, err := os.ReadFile(decompressedFilePath)
 	require.NoError(t, err)
 
 	return fileContent

pkg/storage/stores/shipper/index/compactor/table_compactor_test.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"io"
 	"io/fs"
-	"io/ioutil"
 	"os"
 	"path"
 	"path/filepath"
@@ -523,7 +522,7 @@ func compareCompactedTable(t *testing.T, srcTable string, tableCompactor *tableC
 func readIndexFromFiles(t *testing.T, tablePath string) map[string]map[string]string {
 	tempDir := t.TempDir()
 
-	filesInfo, err := ioutil.ReadDir(tablePath)
+	dirEntries, err := os.ReadDir(tablePath)
 	if err != nil && os.IsNotExist(err) {
 		return map[string]map[string]string{}
 	}
@@ -531,15 +530,15 @@ func readIndexFromFiles(t *testing.T, tablePath string) map[string]map[string]st
 
 	dbRecords := make(map[string]map[string]string)
 
-	for _, fileInfo := range filesInfo {
-		if fileInfo.IsDir() {
+	for _, entry := range dirEntries {
+		if entry.IsDir() {
 			continue
 		}
 
-		filePath := filepath.Join(tablePath, fileInfo.Name())
+		filePath := filepath.Join(tablePath, entry.Name())
 		if strings.HasSuffix(filePath, ".gz") {
-			filePath = filepath.Join(tempDir, fileInfo.Name())
-			testutil.DecompressFile(t, filepath.Join(tablePath, fileInfo.Name()), filePath)
+			filePath = filepath.Join(tempDir, entry.Name())
+			testutil.DecompressFile(t, filepath.Join(tablePath, entry.Name()), filePath)
 		}
 
 		db, err := openBoltdbFileWithNoSync(filePath)

pkg/storage/stores/shipper/index/compactor/util_test.go

@@ -3,7 +3,7 @@ package compactor
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"sort"
 	"testing"
@@ -142,12 +142,12 @@ type table struct {
 func (t *testStore) indexTables() []table {
 	t.t.Helper()
 	res := []table{}
-	indexFilesInfo, err := ioutil.ReadDir(t.indexDir)
+	dirEntries, err := os.ReadDir(t.indexDir)
 	require.NoError(t.t, err)
-	for _, indexFileInfo := range indexFilesInfo {
-		db, err := shipper_util.SafeOpenBoltdbFile(filepath.Join(t.indexDir, indexFileInfo.Name()))
+	for _, entry := range dirEntries {
+		db, err := shipper_util.SafeOpenBoltdbFile(filepath.Join(t.indexDir, entry.Name()))
 		require.NoError(t.t, err)
-		res = append(res, table{name: indexFileInfo.Name(), DB: db})
+		res = append(res, table{name: entry.Name(), DB: db})
 	}
 	return res
 }

pkg/storage/stores/shipper/index/table.go

@@ -3,7 +3,6 @@ package index
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path"
 	"path/filepath"
@@ -351,18 +350,18 @@ func (lt *Table) buildFileName(dbName string) string {
 
 func loadBoltDBsFromDir(dir string, metrics *metrics) (map[string]*bbolt.DB, error) {
 	dbs := map[string]*bbolt.DB{}
-	filesInfo, err := ioutil.ReadDir(dir)
+	dirEntries, err := os.ReadDir(dir)
 	if err != nil {
 		return nil, err
 	}
 
-	for _, fileInfo := range filesInfo {
-		if fileInfo.IsDir() {
+	for _, entry := range dirEntries {
+		if entry.IsDir() {
 			continue
 		}
-		fullPath := filepath.Join(dir, fileInfo.Name())
+		fullPath := filepath.Join(dir, entry.Name())
 
-		if strings.HasSuffix(fileInfo.Name(), indexfile.TempFileSuffix) || strings.HasSuffix(fileInfo.Name(), snapshotFileSuffix) {
+		if strings.HasSuffix(entry.Name(), indexfile.TempFileSuffix) || strings.HasSuffix(entry.Name(), snapshotFileSuffix) {
 			// If an ingester is killed abruptly in the middle of an upload operation it could leave out a temp file which holds the snapshot of db for uploading.
 			// Cleaning up those temp files to avoid problems.
 			if err := os.Remove(fullPath); err != nil {
@@ -395,7 +394,7 @@ func loadBoltDBsFromDir(dir string, metrics *metrics) (map[string]*bbolt.DB, err
 			continue
 		}
 
-		dbs[fileInfo.Name()] = db
+		dbs[entry.Name()] = db
 	}
 
 	return dbs, nil

pkg/storage/stores/shipper/index/table_manager.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -184,7 +183,7 @@ func (tm *TableManager) handoverIndexesToShipper(force bool) {
 
 func (tm *TableManager) loadTables() (map[string]*Table, error) {
 	localTables := make(map[string]*Table)
-	filesInfo, err := ioutil.ReadDir(tm.cfg.IndexDir)
+	dirEntries, err := os.ReadDir(tm.cfg.IndexDir)
 	if err != nil {
 		return nil, err
 	}
@@ -195,16 +194,16 @@ func (tm *TableManager) loadTables() (map[string]*Table, error) {
 		return nil, err
 	}
 
-	for _, fileInfo := range filesInfo {
-		if !re.MatchString(fileInfo.Name()) {
+	for _, entry := range dirEntries {
+		if !re.MatchString(entry.Name()) {
 			continue
 		}
 
 		// since we are moving to keeping files for same table in a folder, if current element is a file we need to move it inside a directory with the same name
 		// i.e file index_123 would be moved to path index_123/index_123.
-		if !fileInfo.IsDir() {
-			level.Info(util_log.Logger).Log("msg", fmt.Sprintf("found a legacy file %s, moving it to folder with same name", fileInfo.Name()))
-			filePath := filepath.Join(tm.cfg.IndexDir, fileInfo.Name())
+		if !entry.IsDir() {
+			level.Info(util_log.Logger).Log("msg", fmt.Sprintf("found a legacy file %s, moving it to folder with same name", entry.Name()))
+			filePath := filepath.Join(tm.cfg.IndexDir, entry.Name())
 
 			// create a folder with .temp suffix since we can't create a directory with same name as file.
 			tempDirPath := filePath + ".temp"
@@ -213,7 +212,7 @@ func (tm *TableManager) loadTables() (map[string]*Table, error) {
 			}
 
 			// move the file to temp dir.
-			if err := os.Rename(filePath, filepath.Join(tempDirPath, fileInfo.Name())); err != nil {
+			if err := os.Rename(filePath, filepath.Join(tempDirPath, entry.Name())); err != nil {
 				return nil, err
 			}
 
@@ -223,17 +222,17 @@ func (tm *TableManager) loadTables() (map[string]*Table, error) {
 			}
 		}
 
-		level.Info(util_log.Logger).Log("msg", fmt.Sprintf("loading table %s", fileInfo.Name()))
-		table, err := LoadTable(filepath.Join(tm.cfg.IndexDir, fileInfo.Name()), tm.cfg.Uploader, tm.indexShipper, tm.cfg.MakePerTenantBuckets, tm.metrics)
+		level.Info(util_log.Logger).Log("msg", fmt.Sprintf("loading table %s", entry.Name()))
+		table, err := LoadTable(filepath.Join(tm.cfg.IndexDir, entry.Name()), tm.cfg.Uploader, tm.indexShipper, tm.cfg.MakePerTenantBuckets, tm.metrics)
 		if err != nil {
 			return nil, err
 		}
 
 		if table == nil {
 			// if table is nil it means it has no files in it so remove the folder for that table.
-			err := os.Remove(filepath.Join(tm.cfg.IndexDir, fileInfo.Name()))
+			err := os.Remove(filepath.Join(tm.cfg.IndexDir, entry.Name()))
 			if err != nil {
-				level.Error(util_log.Logger).Log("msg", "failed to remove empty table folder", "table", fileInfo.Name(), "err", err)
+				level.Error(util_log.Logger).Log("msg", "failed to remove empty table folder", "table", entry.Name(), "err", err)
 			}
 			continue
 		}
@@ -250,7 +249,7 @@ func (tm *TableManager) loadTables() (map[string]*Table, error) {
 			return nil, err
 		}
 
-		localTables[fileInfo.Name()] = table
+		localTables[entry.Name()] = table
 	}
 
 	return localTables, nil

pkg/storage/stores/shipper/index/table_test.go

@@ -3,7 +3,7 @@ package index
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"strconv"
 	"testing"
@@ -104,7 +104,7 @@ func TestLoadTable(t *testing.T) {
 
 	// change a boltdb file to text file which would fail to open.
 	invalidFilePath := filepath.Join(tablePath, "invalid")
-	require.NoError(t, ioutil.WriteFile(invalidFilePath, []byte("invalid boltdb file"), 0o666))
+	require.NoError(t, os.WriteFile(invalidFilePath, []byte("invalid boltdb file"), 0o666))
 
 	// verify that changed boltdb file can't be opened.
 	_, err = local.OpenBoltdbFile(invalidFilePath)
@@ -120,9 +120,9 @@ func TestLoadTable(t *testing.T) {
 	}()
 
 	// verify that we still have 3 files(2 valid, 1 invalid)
-	filesInfo, err := ioutil.ReadDir(tablePath)
+	dirEntries, err := os.ReadDir(tablePath)
 	require.NoError(t, err)
-	require.Len(t, filesInfo, 3)
+	require.Len(t, dirEntries, 3)
 
 	// query the loaded table to see if it has right data.
 	require.NoError(t, table.Snapshot())
@@ -301,9 +301,9 @@ func Test_LoadBoltDBsFromDir(t *testing.T) {
 		require.NoError(t, boltdb.Close())
 	}
 
-	filesInfo, err := ioutil.ReadDir(tablePath)
+	dirEntries, err := os.ReadDir(tablePath)
 	require.NoError(t, err)
-	require.Len(t, filesInfo, 2)
+	require.Len(t, dirEntries, 2)
 }
 
 func TestTable_ImmutableUploads(t *testing.T) {

pkg/storage/stores/shipper/shipper_index_client.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path"
 	"sync"
@@ -126,11 +125,11 @@ func (i *indexClient) getUploaderName() (string, error) {
 		if !os.IsNotExist(err) {
 			return "", err
 		}
-		if err := ioutil.WriteFile(uploaderFilePath, []byte(uploader), 0o666); err != nil {
+		if err := os.WriteFile(uploaderFilePath, []byte(uploader), 0o666); err != nil {
 			return "", err
 		}
 	} else {
-		ub, err := ioutil.ReadFile(uploaderFilePath)
+		ub, err := os.ReadFile(uploaderFilePath)
 		if err != nil {
 			return "", err
 		}

pkg/storage/stores/tsdb/head_manager.go

@@ -3,7 +3,6 @@ package tsdb
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"sort"
@@ -423,7 +422,7 @@ func walsByPeriod(dir string, period period) ([]WalGroup, error) {
 }
 
 func walGroups(dir string, period period) (map[int]*WalGroup, error) {
-	files, err := ioutil.ReadDir(managerWalDir(dir))
+	files, err := os.ReadDir(managerWalDir(dir))
 	if err != nil {
 		return nil, err
 	}

pkg/storage/stores/tsdb/index/index.go

@@ -22,7 +22,6 @@ import (
 	"hash"
 	"hash/crc32"
 	"io"
-	"io/ioutil"
 	"math"
 	"os"
 	"path/filepath"
@@ -1200,7 +1199,7 @@ func (b RealByteSlice) Sub(start, end int) ByteSlice {
 // NewReader returns a new index reader on the given byte slice. It automatically
 // handles different format versions.
 func NewReader(b ByteSlice) (*Reader, error) {
-	return newReader(b, ioutil.NopCloser(nil))
+	return newReader(b, io.NopCloser(nil))
 }
 
 type nopCloser struct{}
@@ -1209,7 +1208,7 @@ func (nopCloser) Close() error { return nil }
 
 // NewFileReader returns a new index reader against the given index file.
 func NewFileReader(path string) (*Reader, error) {
-	b, err := ioutil.ReadFile(path)
+	b, err := os.ReadFile(path)
 	if err != nil {
 		return nil, err
 	}

pkg/storage/stores/tsdb/index/index_test.go

@@ -17,7 +17,6 @@ import (
 	"context"
 	"fmt"
 	"hash/crc32"
-	"io/ioutil"
 	"math/rand"
 	"os"
 	"path/filepath"
@@ -484,7 +483,7 @@ func TestNewFileReaderErrorNoOpenFiles(t *testing.T) {
 	dir := testutil.NewTemporaryDirectory("block", t)
 
 	idxName := filepath.Join(dir.Path(), "index")
-	err := ioutil.WriteFile(idxName, []byte("corrupted contents"), 0o666)
+	err := os.WriteFile(idxName, []byte("corrupted contents"), 0o666)
 	require.NoError(t, err)
 
 	_, err = NewFileReader(idxName)

pkg/storage/stores/tsdb/manager.go

@@ -3,7 +3,7 @@ package tsdb
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"regexp"
 	"strconv"
@@ -95,7 +95,7 @@ func (m *tsdbManager) Start() (err error) {
 
 	// load list of multitenant tsdbs
 	mulitenantDir := managerMultitenantDir(m.dir)
-	files, err := ioutil.ReadDir(mulitenantDir)
+	files, err := os.ReadDir(mulitenantDir)
 	if err != nil {
 		return err
 	}
@@ -116,7 +116,7 @@ func (m *tsdbManager) Start() (err error) {
 		}
 		buckets++
 
-		tsdbs, err := ioutil.ReadDir(filepath.Join(mulitenantDir, bucket))
+		tsdbs, err := os.ReadDir(filepath.Join(mulitenantDir, bucket))
 		if err != nil {
 			level.Warn(m.log).Log(
 				"msg", "failed to open period bucket dir",

pkg/storage/stores/tsdb/single_file_index.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"context"
 	"io"
-	"io/ioutil"
+	"os"
 	"strings"
 	"time"
 
@@ -86,7 +86,7 @@ type TSDBIndex struct {
 // Return the index as well as the underlying []byte which isn't exposed as an index
 // method but is helpful for building an io.reader for the index shipper
 func NewTSDBIndexFromFile(location string, gzip bool) (*TSDBIndex, []byte, error) {
-	raw, err := ioutil.ReadFile(location)
+	raw, err := os.ReadFile(location)
 	if err != nil {
 		return nil, nil, err
 	}

pkg/util/cfg/cfg_test.go

@@ -2,7 +2,6 @@ package cfg
 
 import (
 	"flag"
-	"io/ioutil"
 	"os"
 	"testing"
 	"time"
@@ -69,7 +68,7 @@ tls:
 
 func TestDefaultUnmarshal(t *testing.T) {
 	testContext := func(yamlString string, args []string) TestConfigWrapper {
-		file, err := ioutil.TempFile("", "config.yaml")
+		file, err := os.CreateTemp("", "config.yaml")
 		defer func() {
 			os.Remove(file.Name())
 		}()

pkg/util/cfg/dynamic_test.go

@@ -2,7 +2,7 @@ package cfg
 
 import (
 	"flag"
-	"io/ioutil"
+	"os"
 	"testing"
 	"time"
 
@@ -21,7 +21,7 @@ server:
 		data := NewDynamicConfig(mockApplyDynamicConfig)
 		fs := flag.NewFlagSet(t.Name(), flag.PanicOnError)
 
-		file, err := ioutil.TempFile("", "config.yaml")
+		file, err := os.CreateTemp("", "config.yaml")
 		require.NoError(t, err)
 		_, err = file.WriteString(config)
 		require.NoError(t, err)

pkg/util/cfg/files.go

@@ -4,7 +4,6 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"strconv"
 	"strings"
@@ -21,7 +20,7 @@ func JSON(f *string) Source {
 			return nil
 		}
 
-		j, err := ioutil.ReadFile(*f)
+		j, err := os.ReadFile(*f)
 		if err != nil {
 			return err
 		}
@@ -43,7 +42,7 @@ func dJSON(y []byte) Source {
 // using https://pkg.go.dev/github.com/drone/envsubst?tab=overview
 func YAML(f string, expandEnvVars bool, strict bool) Source {
 	return func(dst Cloneable) error {
-		y, err := ioutil.ReadFile(f)
+		y, err := os.ReadFile(f)
 		if err != nil {
 			return err
 		}

pkg/util/http_test.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"context"
 	"html/template"
-	"io/ioutil"
+	"io"
 	"math/rand"
 	"net/http"
 	"net/http/httptest"
@@ -215,6 +215,6 @@ func (b bytesBuffered) BytesBuffer() *bytes.Buffer {
 }
 
 func TestIsRequestBodyTooLargeRegression(t *testing.T) {
-	_, err := ioutil.ReadAll(http.MaxBytesReader(httptest.NewRecorder(), ioutil.NopCloser(bytes.NewReader([]byte{1, 2, 3, 4})), 1))
+	_, err := io.ReadAll(http.MaxBytesReader(httptest.NewRecorder(), io.NopCloser(bytes.NewReader([]byte{1, 2, 3, 4})), 1))
 	assert.True(t, util.IsRequestBodyTooLarge(err))
 }

pkg/util/server/error_test.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -55,7 +55,7 @@ func Test_writeError(t *testing.T) {
 			rec := httptest.NewRecorder()
 			WriteError(tt.err, rec)
 			require.Equal(t, tt.expectedStatus, rec.Result().StatusCode)
-			b, err := ioutil.ReadAll(rec.Result().Body)
+			b, err := io.ReadAll(rec.Result().Body)
 			if err != nil {
 				t.Fatal(err)
 			}

pkg/util/unmarshal/legacy/unmarshal_test.go

@@ -1,7 +1,7 @@
 package unmarshal
 
 import (
-	"io/ioutil"
+	"io"
 	"log"
 	"strings"
 	"testing"
@@ -49,7 +49,7 @@ func Test_DecodePushRequest(t *testing.T) {
 
 	for i, pushTest := range pushTests {
 		var actual logproto.PushRequest
-		closer := ioutil.NopCloser(strings.NewReader(pushTest.actual))
+		closer := io.NopCloser(strings.NewReader(pushTest.actual))
 
 		err := DecodePushRequest(closer, &actual)
 		require.NoError(t, err)

pkg/util/unmarshal/unmarshal_test.go

@@ -2,7 +2,7 @@ package unmarshal
 
 import (
 	"fmt"
-	"io/ioutil"
+	"io"
 	"strings"
 	"testing"
 	"time"
@@ -50,7 +50,7 @@ var pushTests = []struct {
 func Test_DecodePushRequest(t *testing.T) {
 	for i, pushTest := range pushTests {
 		var actual logproto.PushRequest
-		closer := ioutil.NopCloser(strings.NewReader(pushTest.actual))
+		closer := io.NopCloser(strings.NewReader(pushTest.actual))
 
 		err := DecodePushRequest(closer, &actual)
 		require.NoError(t, err)

tools/lambda-promtail/lambda-promtail/kinesis_test.go

@@ -3,7 +3,7 @@ package main
 import (
 	"context"
 	"encoding/json"
-	"io/ioutil"
+	"os"
 	"testing"
 
 	"github.com/aws/aws-lambda-go/events"
@@ -34,7 +34,7 @@ func (b *MockBatch) createPushRequest() (*logproto.PushRequest, int) {
 }
 
 func ReadJSONFromFile(t *testing.T, inputFile string) []byte {
-	inputJSON, err := ioutil.ReadFile(inputFile)
+	inputJSON, err := os.ReadFile(inputFile)
 	if err != nil {
 		t.Errorf("could not open test file. details: %v", err)
 	}
@@ -43,7 +43,7 @@ func ReadJSONFromFile(t *testing.T, inputFile string) []byte {
 }
 
 func TestLambdaPromtail_KinesisParseEvents(t *testing.T) {
-	inputJson, err := ioutil.ReadFile("../testdata/kinesis-event.json")
+	inputJson, err := os.ReadFile("../testdata/kinesis-event.json")
 
 	if err != nil {
 		t.Errorf("could not open test file. details: %v", err)

tools/querytee/proxy_backend.go

@@ -3,7 +3,6 @@ package querytee
 import (
 	"context"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/url"
@@ -107,7 +106,7 @@ func (b *ProxyBackend) doBackendRequest(req *http.Request) (int, []byte, error)
 
 	// Read the entire response body.
 	defer res.Body.Close()
-	body, err := ioutil.ReadAll(res.Body)
+	body, err := io.ReadAll(res.Body)
 	if err != nil {
 		return 0, nil, errors.Wrap(err, "reading backend response")
 	}

tools/querytee/proxy_endpoint.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"strconv"
 	"strings"
@@ -85,7 +84,7 @@ func (p *ProxyEndpoint) executeBackendRequests(r *http.Request, resCh chan *back
 	)
 
 	if r.Body != nil {
-		body, err = ioutil.ReadAll(r.Body)
+		body, err = io.ReadAll(r.Body)
 		if err != nil {
 			level.Warn(p.logger).Log("msg", "Unable to read request body", "err", err)
 			return
@@ -94,7 +93,7 @@ func (p *ProxyEndpoint) executeBackendRequests(r *http.Request, resCh chan *back
 			level.Warn(p.logger).Log("msg", "Unable to close request body", "err", err)
 		}
 
-		r.Body = ioutil.NopCloser(bytes.NewReader(body))
+		r.Body = io.NopCloser(bytes.NewReader(body))
 		if err := r.ParseForm(); err != nil {
 			level.Warn(p.logger).Log("msg", "Unable to parse form", "err", err)
 		}
@@ -115,7 +114,7 @@ func (p *ProxyEndpoint) executeBackendRequests(r *http.Request, resCh chan *back
 				start      = time.Now()
 			)
 			if len(body) > 0 {
-				bodyReader = ioutil.NopCloser(bytes.NewReader(body))
+				bodyReader = io.NopCloser(bytes.NewReader(body))
 			}
 
 			status, body, err := b.ForwardRequest(r, bodyReader)

tools/querytee/proxy_test.go

@@ -2,7 +2,7 @@ package querytee
 
 import (
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
@@ -179,7 +179,7 @@ func Test_Proxy_RequestsForwarding(t *testing.T) {
 			require.NoError(t, err)
 
 			defer res.Body.Close()
-			body, err := ioutil.ReadAll(res.Body)
+			body, err := io.ReadAll(res.Body)
 			require.NoError(t, err)
 
 			assert.Equal(t, testData.expectedStatus, res.StatusCode)
@@ -330,7 +330,7 @@ func TestProxy_Passthrough(t *testing.T) {
 				require.NoError(t, err)
 
 				defer res.Body.Close()
-				body, err := ioutil.ReadAll(res.Body)
+				body, err := io.ReadAll(res.Body)
 				require.NoError(t, err)
 
 				assert.Equal(t, query.expectedStatusCode, res.StatusCode)