refactor: move from io/ioutil to io and os package (#1772)

The io/ioutil package has been deprecated as of Go 1.16, see
https://golang.org/doc/go1.16#ioutil. This commit replaces the existing
io/ioutil functions with their new definitions in io and os packages.

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

pkg/utils/file.go

@@ -4,7 +4,6 @@ import (
 	"archive/zip"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"os"
 	"os/user"
@@ -108,10 +107,10 @@ func EmptyDir(path string) error {
 // ListDir will return the contents of a given directory path as a string slice
 func ListDir(path string) ([]string, error) {
 	var dirPaths []string
-	files, err := ioutil.ReadDir(path)
+	files, err := os.ReadDir(path)
 	if err != nil {
 		path = filepath.Dir(path)
-		files, err = ioutil.ReadDir(path)
+		files, err = os.ReadDir(path)
 		if err != nil {
 			return dirPaths, err
 		}
@@ -196,7 +195,7 @@ func WriteFile(path string, file []byte) error {
 		return fmt.Errorf("cannot ensure path %s", pathErr)
 	}
 
-	err := ioutil.WriteFile(path, file, 0755)
+	err := os.WriteFile(path, file, 0755)
 	if err != nil {
 		return fmt.Errorf("write error for thumbnail %s: %s ", path, err)
 	}

pkg/utils/file_test.go

@@ -1,7 +1,6 @@
 package utils
 
 import (
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"testing"
@@ -53,11 +52,11 @@ func TestDirExists(t *testing.T) {
 	const st = "stash_tmp"
 
 	tmp := os.TempDir()
-	tmpDir, err := ioutil.TempDir(tmp, st) // create a tmp dir in the system's tmp folder
+	tmpDir, err := os.MkdirTemp(tmp, st) // create a tmp dir in the system's tmp folder
 	if err == nil {
 		defer os.RemoveAll(tmpDir)
 
-		tmpFile, err := ioutil.TempFile(tmpDir, st)
+		tmpFile, err := os.CreateTemp(tmpDir, st)
 		if err != nil {
 			return
 		}

pkg/utils/image.go

@@ -5,7 +5,7 @@ import (
 	"crypto/tls"
 	"encoding/base64"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"regexp"
 	"strings"
@@ -66,7 +66,7 @@ func ReadImageFromURL(url string) ([]byte, error) {
 
 	defer resp.Body.Close()
 
-	body, err := ioutil.ReadAll(resp.Body)
+	body, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return nil, err
 	}