Use io/os instead of deprecated ioutil

Signed-off-by: LogicalShark <maralder@google.com>

Author: LogicalShark

cmd/auth-provider-gcp/app/getcredentials.go

@@ -19,7 +19,7 @@ package app
 import (
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"os"
 
@@ -112,7 +112,7 @@ func getCredentials(authFlow string) error {
 	if err != nil {
 		return err
 	}
-	unparsedRequest, err := ioutil.ReadAll(os.Stdin)
+	unparsedRequest, err := io.ReadAll(os.Stdin)
 	if err != nil {
 		return err
 	}

cmd/gke-gcloud-auth-plugin/cred.go

@@ -11,7 +11,7 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"os/exec"
 	"path/filepath"
 	"strings"
@@ -369,7 +369,7 @@ func executeCommand(name string, arg ...string) ([]byte, error) {
 }
 
 func readFile(filename string) ([]byte, error) {
-	return ioutil.ReadFile(filename)
+	return os.ReadFile(filename)
 }
 
 func timeNow() time.Time {

pkg/credentialconfig/config.go

@@ -22,7 +22,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -108,7 +107,7 @@ func ReadDockercfgFile(searchPaths []string) (cfg DockerConfig, err error) {
 			continue
 		}
 		klog.V(4).Infof("looking for .dockercfg at %s", absDockerConfigFileLocation)
-		contents, err := ioutil.ReadFile(absDockerConfigFileLocation)
+		contents, err := os.ReadFile(absDockerConfigFileLocation)
 		if os.IsNotExist(err) {
 			continue
 		}
@@ -160,7 +159,7 @@ func ReadDockerConfigJSONFile(searchPaths []string) (cfg DockerConfig, err error
 func ReadSpecificDockerConfigJSONFile(filePath string) (cfg DockerConfig, err error) {
 	var contents []byte
 
-	if contents, err = ioutil.ReadFile(filePath); err != nil {
+	if contents, err = os.ReadFile(filePath); err != nil {
 		return nil, err
 	}
 	return readDockerConfigJSONFileFromBytes(contents)
@@ -212,7 +211,7 @@ func ReadURL(url string, client *http.Client, header *http.Header) (body []byte,
 	}
 
 	limitedReader := &io.LimitedReader{R: resp.Body, N: maxReadLength}
-	contents, err := ioutil.ReadAll(limitedReader)
+	contents, err := io.ReadAll(limitedReader)
 	if err != nil {
 		return nil, err
 	}

pkg/credentialconfig/config_test.go

@@ -19,7 +19,6 @@ package credentialconfig
 import (
 	"encoding/base64"
 	"encoding/json"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"reflect"
@@ -33,7 +32,7 @@ func TestReadDockerConfigFile(t *testing.T) {
 	//test dockerconfig json
 	inputDockerconfigJSONFile := "{ \"auths\": { \"http://foo.example.com\":{\"auth\":\"Zm9vOmJhcgo=\",\"email\":\"foo@example.com\"}}}"
 
-	preferredPath, err := ioutil.TempDir("", "test_foo_bar_dockerconfigjson_")
+	preferredPath, err := os.MkdirTemp("", "test_foo_bar_dockerconfigjson_")
 	if err != nil {
 		t.Fatalf("Creating tmp dir fail: %v", err)
 		return

pkg/gcpcredential/gcpcredential.go

@@ -18,8 +18,8 @@ package gcpcredential
 
 import (
 	"encoding/json"
-	"io/ioutil"
 	"net/http"
+	"os"
 	"os/exec"
 	"runtime"
 	"strings"
@@ -102,7 +102,7 @@ func onGCEVM() bool {
 		}
 		name = fields[1]
 	} else {
-		data, err := ioutil.ReadFile(GCEProductNameFile)
+		data, err := os.ReadFile(GCEProductNameFile)
 		if err != nil {
 			klog.V(2).Infof("Error while reading product_name: %v", err)
 			return false

providers/gce/gcpcredential/credentialutil.go

@@ -21,7 +21,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 
 	"k8s.io/cloud-provider/credentialconfig"
@@ -68,7 +67,7 @@ func ReadURL(url string, client *http.Client, header *http.Header) (body []byte,
 	}
 
 	limitedReader := &io.LimitedReader{R: resp.Body, N: maxReadLength}
-	contents, err := ioutil.ReadAll(limitedReader)
+	contents, err := io.ReadAll(limitedReader)
 	if err != nil {
 		return nil, err
 	}