Replace deprecated ioutil package

pkg/mapper/configmap/yaml_test.go

@@ -2,7 +2,7 @@ package configmap
 
 import (
 	"context"
-	"io/ioutil"
+	"os"
 	"path"
 	"reflect"
 	"strings"
@@ -163,7 +163,7 @@ func TestConfigMap(t *testing.T) {
 
 func configMapFromYaml(fileName string) (*v1.ConfigMap, error) {
 	var cm v1.ConfigMap
-	data, err := ioutil.ReadFile(path.Join("./yaml/", fileName))
+	data, err := os.ReadFile(path.Join("./yaml/", fileName))
 	if err != nil {
 		return nil, err
 	}

pkg/server/server_test.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"errors"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"reflect"
@@ -27,7 +27,7 @@ import (
 
 func verifyBodyContains(t *testing.T, resp *httptest.ResponseRecorder, s string) {
 	t.Helper()
-	b, err := ioutil.ReadAll(resp.Body)
+	b, err := io.ReadAll(resp.Body)
 	if err != nil {
 		t.Fatalf("Failed to read body from ResponseRecorder, this should not happen")
 	}
@@ -38,7 +38,7 @@ func verifyBodyContains(t *testing.T, resp *httptest.ResponseRecorder, s string)
 
 func verifyAuthResult(t *testing.T, resp *httptest.ResponseRecorder, expected authenticationv1beta1.TokenReview) {
 	t.Helper()
-	b, err := ioutil.ReadAll(resp.Body)
+	b, err := io.ReadAll(resp.Body)
 	if err != nil {
 		t.Fatalf("Failed to read body from ResponseRecorder, this should not happen.")
 	}

pkg/token/filecache.go

@@ -4,15 +4,15 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"github.com/aws/aws-sdk-go/aws/credentials"
-	"github.com/gofrs/flock"
-	"gopkg.in/yaml.v2"
 	"io/fs"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"runtime"
 	"time"
+
+	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/gofrs/flock"
+	"gopkg.in/yaml.v2"
 )
 
 // env variable name for custom credential cache file location
@@ -36,11 +36,11 @@ func (osFS) Stat(filename string) (os.FileInfo, error) {
 }
 
 func (osFS) ReadFile(filename string) ([]byte, error) {
-	return ioutil.ReadFile(filename)
+	return os.ReadFile(filename)
 }
 
 func (osFS) WriteFile(filename string, data []byte, perm os.FileMode) error {
-	return ioutil.WriteFile(filename, data, perm)
+	return os.WriteFile(filename, data, perm)
 }
 
 func (osFS) MkdirAll(path string, perm os.FileMode) error {

pkg/token/token.go

@@ -20,7 +20,7 @@ import (
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/url"
 	"os"
@@ -570,7 +570,7 @@ func (v tokenVerifier) Verify(token string) (*Identity, error) {
 	}
 	defer response.Body.Close()
 
-	responseBody, err := ioutil.ReadAll(response.Body)
+	responseBody, err := io.ReadAll(response.Body)
 	if err != nil {
 		return nil, NewSTSError(fmt.Sprintf("error reading HTTP result: %v", err))
 	}

pkg/token/token_test.go

@@ -7,7 +7,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"os"
@@ -87,7 +86,7 @@ func toToken(url string) string {
 func newVerifier(partition string, statusCode int, body string, err error) Verifier {
 	var rc io.ReadCloser
 	if body != "" {
-		rc = ioutil.NopCloser(bytes.NewReader([]byte(body)))
+		rc = io.NopCloser(bytes.NewReader([]byte(body)))
 	}
 	return tokenVerifier{
 		client: &http.Client{
@@ -246,7 +245,7 @@ func TestVerifyNoRedirectsFollowed(t *testing.T) {
 	}
 	defer resp.Body.Close()
 	if resp.Header.Get("Location") != ts2.URL && resp.StatusCode != http.StatusFound {
-		body, _ := ioutil.ReadAll(resp.Body)
+		body, _ := io.ReadAll(resp.Body)
 		fmt.Printf("%#v\n", resp)
 		fmt.Println(string(body))
 		t.Error("Unexpectedly followed redirect")

tests/e2e/apiserver_test.go

@@ -21,7 +21,7 @@ import (
 	"time"
 
 	"bytes"
-	"io/ioutil"
+
 	yamlutil "k8s.io/apimachinery/pkg/util/yaml"
 
 	. "github.com/onsi/ginkgo/v2"
@@ -47,7 +47,7 @@ var _ = SIGDescribe("apiserver", framework.WithDisruptive(), func() {
 		BeforeEach(func() {
 			jobPath := filepath.Join(os.Getenv("BASE_DIR"), "apiserver-restart.yaml")
 
-			b, _ := ioutil.ReadFile(jobPath)
+			b, _ := os.ReadFile(jobPath)
 			decoder := yamlutil.NewYAMLOrJSONDecoder(bytes.NewReader(b), 100)
 			jobSpec := &batchv1.Job{}
 			_ = decoder.Decode(&jobSpec)