Remove use of io/ioutil package because it's deprecated

.gitignore

@@ -24,5 +24,6 @@ dist/
 Makefile.local
 
 .idea
+.vscode
 compose
 compose-simple

.golangci.yml

@@ -13,7 +13,6 @@ linters-settings:
   staticcheck:
     checks:
       - all
-      - "-SA1019" # Disable because too many file uses io/ioutil now, will fix later
   errcheck:
     # path to a file containing a list of functions to exclude from checking
     # see https://github.com/kisielk/errcheck#excluding-functions for details

cmd/cortex/main.go

@@ -5,7 +5,7 @@ import (
 	"crypto/sha256"
 	"flag"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"math/rand"
 	"os"
 	"runtime"
@@ -204,7 +204,7 @@ func main() {
 func parseConfigFileParameter(args []string) (configFile string, expandEnv bool) {
 	// ignore errors and any output here. Any flag errors will be reported by main flag.Parse() call.
 	fs := flag.NewFlagSet("", flag.ContinueOnError)
-	fs.SetOutput(ioutil.Discard)
+	fs.SetOutput(io.Discard)
 
 	// usage not used in these functions.
 	fs.StringVar(&configFile, configFileOption, "", "")
@@ -223,7 +223,7 @@ func parseConfigFileParameter(args []string) (configFile string, expandEnv bool)
 
 // LoadConfig read YAML-formatted config from filename into cfg.
 func LoadConfig(filename string, expandENV bool, cfg *cortex.Config) error {
-	buf, err := ioutil.ReadFile(filename)
+	buf, err := os.ReadFile(filename)
 	if err != nil {
 		return errors.Wrap(err, "Error reading config file")
 	}

integration/api_endpoints_test.go

@@ -5,7 +5,7 @@ package integration
 
 import (
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"testing"
 
@@ -55,7 +55,7 @@ func TestConfigAPIEndpoint(t *testing.T) {
 	require.NoError(t, err)
 
 	defer runutil.ExhaustCloseWithErrCapture(&err, res.Body, "config API response")
-	body, err := ioutil.ReadAll(res.Body)
+	body, err := io.ReadAll(res.Body)
 	require.NoError(t, err)
 	require.Equal(t, http.StatusOK, res.StatusCode)
 

integration/e2e/scenario_test.go

@@ -6,7 +6,7 @@ package e2e_test
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
+	"io"
 	"testing"
 	"time"
 
@@ -65,13 +65,13 @@ func testMinioWorking(t *testing.T, m *e2e.HTTPService) {
 
 	r, err := bkt.Get(ctx, "recipe")
 	require.NoError(t, err)
-	b, err = ioutil.ReadAll(r)
+	b, err = io.ReadAll(r)
 	require.NoError(t, err)
 	require.Equal(t, "Just go to Pastry Shop and buy.", string(b))
 
 	r, err = bkt.Get(ctx, "mom/recipe")
 	require.NoError(t, err)
-	b, err = ioutil.ReadAll(r)
+	b, err = io.ReadAll(r)
 	require.NoError(t, err)
 	require.Equal(t, "https://www.bbcgoodfood.com/recipes/strawberry-cheesecake-4-easy-steps", string(b))
 }

integration/e2e/service.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"context"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net"
 	"os/exec"
 	"regexp"
@@ -418,7 +418,7 @@ func (p *HTTPReadinessProbe) Ready(service *ConcreteService) (err error) {
 	}
 
 	defer runutil.ExhaustCloseWithErrCapture(&err, res.Body, "response readiness")
-	body, _ := ioutil.ReadAll(res.Body)
+	body, _ := io.ReadAll(res.Body)
 
 	if res.StatusCode < p.expectedStatusRangeStart || res.StatusCode > p.expectedStatusRangeEnd {
 		return fmt.Errorf("expected code in range: [%v, %v], got status code: %v and body: %v", p.expectedStatusRangeStart, p.expectedStatusRangeEnd, res.StatusCode, string(body))
@@ -534,7 +534,7 @@ func (s *HTTPService) Metrics() (_ string, err error) {
 	}
 
 	defer runutil.ExhaustCloseWithErrCapture(&err, res.Body, "metrics response")
-	body, err := ioutil.ReadAll(res.Body)
+	body, err := io.ReadAll(res.Body)
 
 	return string(body), err
 }

integration/e2e/util.go

@@ -2,7 +2,6 @@ package e2e
 
 import (
 	"context"
-	"io/ioutil"
 	"math"
 	"math/rand"
 	"net/http"
@@ -157,7 +156,7 @@ func GetTempDirectory() (string, error) {
 		}
 	}
 
-	tmpDir, err := ioutil.TempDir(dir, "e2e_integration_test")
+	tmpDir, err := os.MkdirTemp(dir, "e2e_integration_test")
 	if err != nil {
 		return "", err
 	}

integration/querier_remote_read_test.go

@@ -6,7 +6,7 @@ package integration
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"testing"
 	"time"
@@ -102,7 +102,7 @@ func TestQuerierRemoteRead(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, http.StatusOK, httpResp.StatusCode)
 
-	compressed, err = ioutil.ReadAll(httpResp.Body)
+	compressed, err = io.ReadAll(httpResp.Body)
 	require.NoError(t, err)
 
 	uncompressed, err := snappy.Decode(nil, compressed)

integration/util.go

@@ -5,7 +5,6 @@ package integration
 
 import (
 	"bytes"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -44,14 +43,14 @@ func writeFileToSharedDir(s *e2e.Scenario, dst string, content []byte) error {
 		return err
 	}
 
-	return ioutil.WriteFile(
+	return os.WriteFile(
 		dst,
 		content,
 		os.ModePerm)
 }
 
 func copyFileToSharedDir(s *e2e.Scenario, src, dst string) error {
-	content, err := ioutil.ReadFile(filepath.Join(getCortexProjectDir(), src))
+	content, err := os.ReadFile(filepath.Join(getCortexProjectDir(), src))
 	if err != nil {
 		return errors.Wrapf(err, "unable to read local file %s", src)
 	}

pkg/alertmanager/alertmanager_http_test.go

@@ -2,7 +2,7 @@ package alertmanager
 
 import (
 	"context"
-	"io/ioutil"
+	"io"
 	"net/http/httptest"
 	"testing"
 	"time"
@@ -77,7 +77,7 @@ func TestMultitenantAlertmanager_GetStatusHandler(t *testing.T) {
 
 		resp := w.Result()
 		require.Equal(t, 200, w.Code)
-		body, _ := ioutil.ReadAll(resp.Body)
+		body, _ := io.ReadAll(resp.Body)
 		content := string(body)
 		require.Contains(t, content, tt.content)
 		require.NotContains(t, content, tt.nocontent)

pkg/alertmanager/alertstore/bucketclient/bucket_client.go

@@ -3,7 +3,7 @@ package bucketclient
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
+	"io"
 	"strings"
 	"sync"
 
@@ -186,7 +186,7 @@ func (s *BucketAlertStore) get(ctx context.Context, bkt objstore.Bucket, name st
 
 	defer runutil.CloseWithLogOnErr(s.logger, readCloser, "close bucket reader")
 
-	buf, err := ioutil.ReadAll(readCloser)
+	buf, err := io.ReadAll(readCloser)
 	if err != nil {
 		return errors.Wrapf(err, "failed to read alertmanager config for user %s", name)
 	}

pkg/alertmanager/alertstore/local/store.go

@@ -3,7 +3,6 @@ package local
 import (
 	"context"
 	"flag"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -141,7 +140,7 @@ func (f *Store) reloadConfigs() (map[string]alertspb.AlertConfigDesc, error) {
 		}
 
 		// Load the file to be returned by the store.
-		content, err := ioutil.ReadFile(path)
+		content, err := os.ReadFile(path)
 		if err != nil {
 			return errors.Wrapf(err, "unable to read alertmanager config %s", path)
 		}

pkg/alertmanager/alertstore/local/store_test.go

@@ -3,7 +3,6 @@ package local
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"testing"
@@ -29,11 +28,11 @@ func TestStore_ListAllUsers(t *testing.T) {
 	{
 		user1Cfg := prepareAlertmanagerConfig("user-1")
 		user2Cfg := prepareAlertmanagerConfig("user-2")
-		require.NoError(t, ioutil.WriteFile(filepath.Join(storeDir, "user-1.yaml"), []byte(user1Cfg), os.ModePerm))
-		require.NoError(t, ioutil.WriteFile(filepath.Join(storeDir, "user-2.yaml"), []byte(user2Cfg), os.ModePerm))
+		require.NoError(t, os.WriteFile(filepath.Join(storeDir, "user-1.yaml"), []byte(user1Cfg), os.ModePerm))
+		require.NoError(t, os.WriteFile(filepath.Join(storeDir, "user-2.yaml"), []byte(user2Cfg), os.ModePerm))
 
 		// The following file is expected to be skipped.
-		require.NoError(t, ioutil.WriteFile(filepath.Join(storeDir, "user-3.unsupported-extension"), []byte{}, os.ModePerm))
+		require.NoError(t, os.WriteFile(filepath.Join(storeDir, "user-3.unsupported-extension"), []byte{}, os.ModePerm))
 
 		users, err := store.ListAllUsers(ctx)
 		require.NoError(t, err)
@@ -55,8 +54,8 @@ func TestStore_GetAlertConfig(t *testing.T) {
 	{
 		user1Cfg := prepareAlertmanagerConfig("user-1")
 		user2Cfg := prepareAlertmanagerConfig("user-2")
-		require.NoError(t, ioutil.WriteFile(filepath.Join(storeDir, "user-1.yaml"), []byte(user1Cfg), os.ModePerm))
-		require.NoError(t, ioutil.WriteFile(filepath.Join(storeDir, "user-2.yaml"), []byte(user2Cfg), os.ModePerm))
+		require.NoError(t, os.WriteFile(filepath.Join(storeDir, "user-1.yaml"), []byte(user1Cfg), os.ModePerm))
+		require.NoError(t, os.WriteFile(filepath.Join(storeDir, "user-2.yaml"), []byte(user2Cfg), os.ModePerm))
 
 		config, err := store.GetAlertConfig(ctx, "user-1")
 		require.NoError(t, err)
@@ -82,7 +81,7 @@ func TestStore_GetAlertConfigs(t *testing.T) {
 	// The storage contains some configs.
 	{
 		user1Cfg := prepareAlertmanagerConfig("user-1")
-		require.NoError(t, ioutil.WriteFile(filepath.Join(storeDir, "user-1.yaml"), []byte(user1Cfg), os.ModePerm))
+		require.NoError(t, os.WriteFile(filepath.Join(storeDir, "user-1.yaml"), []byte(user1Cfg), os.ModePerm))
 
 		configs, err := store.GetAlertConfigs(ctx, []string{"user-1", "user-2"})
 		require.NoError(t, err)
@@ -92,7 +91,7 @@ func TestStore_GetAlertConfigs(t *testing.T) {
 
 		// Add another user config.
 		user2Cfg := prepareAlertmanagerConfig("user-2")
-		require.NoError(t, ioutil.WriteFile(filepath.Join(storeDir, "user-2.yaml"), []byte(user2Cfg), os.ModePerm))
+		require.NoError(t, os.WriteFile(filepath.Join(storeDir, "user-2.yaml"), []byte(user2Cfg), os.ModePerm))
 
 		configs, err = store.GetAlertConfigs(ctx, []string{"user-1", "user-2"})
 		require.NoError(t, err)

pkg/alertmanager/api.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -111,7 +110,7 @@ func (am *MultitenantAlertmanager) SetUserConfig(w http.ResponseWriter, r *http.
 		input = r.Body
 	}
 
-	payload, err := ioutil.ReadAll(input)
+	payload, err := io.ReadAll(input)
 	if err != nil {
 		level.Error(logger).Log("msg", errReadingConfiguration, "err", err.Error())
 		http.Error(w, fmt.Sprintf("%s: %s", errReadingConfiguration, err.Error()), http.StatusBadRequest)
@@ -223,7 +222,7 @@ func validateUserConfig(logger log.Logger, cfg alertspb.AlertConfigDesc, limits
 	// not to configured data dir, and on the flipside, it'll fail if we can't write
 	// to tmpDir. Ignoring both cases for now as they're ultra rare but will revisit if
 	// we see this in the wild.
-	userTempDir, err := ioutil.TempDir("", "validate-config-"+cfg.User)
+	userTempDir, err := os.MkdirTemp("", "validate-config-"+cfg.User)
 	if err != nil {
 		return err
 	}

pkg/alertmanager/api_test.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"context"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -553,7 +553,7 @@ template_files:
 			am.SetUserConfig(w, req.WithContext(ctx))
 			resp := w.Result()
 
-			body, err := ioutil.ReadAll(resp.Body)
+			body, err := io.ReadAll(resp.Body)
 			require.NoError(t, err)
 
 			if tc.err == nil {
@@ -688,7 +688,7 @@ receivers:
 	resp := w.Result()
 	require.Equal(t, http.StatusOK, resp.StatusCode)
 	require.Equal(t, "application/yaml", resp.Header.Get("Content-Type"))
-	body, err := ioutil.ReadAll(resp.Body)
+	body, err := io.ReadAll(resp.Body)
 	require.NoError(t, err)
 	old, err := yaml.Marshal(testCases)
 	require.NoError(t, err)

pkg/alertmanager/distributor.go

@@ -3,7 +3,7 @@ package alertmanager
 import (
 	"context"
 	"hash/fnv"
-	"io/ioutil"
+	"io"
 	"math/rand"
 	"net/http"
 	"path"
@@ -164,7 +164,7 @@ func (d *Distributor) doQuorum(userID string, w http.ResponseWriter, r *http.Req
 	var body []byte
 	var err error
 	if r.Body != nil {
-		body, err = ioutil.ReadAll(http.MaxBytesReader(w, r.Body, d.maxRecvMsgSize))
+		body, err = io.ReadAll(http.MaxBytesReader(w, r.Body, d.maxRecvMsgSize))
 		if err != nil {
 			if util.IsRequestBodyTooLarge(err) {
 				http.Error(w, "Request body too large", http.StatusRequestEntityTooLarge)
@@ -233,7 +233,7 @@ func (d *Distributor) doUnary(userID string, w http.ResponseWriter, r *http.Requ
 		return
 	}
 
-	body, err := ioutil.ReadAll(http.MaxBytesReader(w, r.Body, d.maxRecvMsgSize))
+	body, err := io.ReadAll(http.MaxBytesReader(w, r.Body, d.maxRecvMsgSize))
 	if err != nil {
 		if util.IsRequestBodyTooLarge(err) {
 			http.Error(w, "Request body too large", http.StatusRequestEntityTooLarge)