refactor: move from io/ioutil to io and os package (#2236)

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/storagesvc/client/client.go

@@ -22,7 +22,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"mime/multipart"
 	"net/http"
 	"net/url"
@@ -101,7 +100,7 @@ func (c *Client) Upload(ctx context.Context, filePath string, metadata *map[stri
 		return "", err
 	}
 	defer resp.Body.Close()
-	body, err := ioutil.ReadAll(resp.Body)
+	body, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return "", err
 	}

pkg/storagesvc/client/storagesvc_test.go

@@ -21,7 +21,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"os"
 	"testing"
@@ -50,7 +49,7 @@ func panicIf(err error) {
 }
 
 func MakeTestFile(size int) *os.File {
-	f, err := ioutil.TempFile("", "storagesvc_test_")
+	f, err := os.CreateTemp("", "storagesvc_test_")
 	panicIf(err)
 
 	_, err = f.Write(bytes.Repeat([]byte("."), size))
@@ -158,7 +157,7 @@ func TestS3StorageService(t *testing.T) {
 	panicIf(err)
 	defer reader.Close()
 
-	retThroughMinio, err := ioutil.TempFile("", "storagesvc_verify_minio_")
+	retThroughMinio, err := os.CreateTemp("", "storagesvc_verify_minio_")
 	panicIf(err)
 	defer os.Remove(retThroughMinio.Name())
 
@@ -170,7 +169,7 @@ func TestS3StorageService(t *testing.T) {
 	}
 
 	// Retrieve file through API
-	retThroughAPI, err := ioutil.TempFile("", "storagesvc_verify_")
+	retThroughAPI, err := os.CreateTemp("", "storagesvc_verify_")
 	panicIf(err)
 	os.Remove(retThroughAPI.Name())
 
@@ -179,9 +178,9 @@ func TestS3StorageService(t *testing.T) {
 	defer os.Remove(retThroughAPI.Name())
 
 	// compare contents
-	contentsMinio, err := ioutil.ReadFile(retThroughMinio.Name())
+	contentsMinio, err := os.ReadFile(retThroughMinio.Name())
 	panicIf(err)
-	contentsAPI, err := ioutil.ReadFile(retThroughAPI.Name())
+	contentsAPI, err := os.ReadFile(retThroughAPI.Name())
 	panicIf(err)
 	if !bytes.Equal(contentsMinio, contentsAPI) {
 		log.Panic("Contents don't match")
@@ -228,7 +227,7 @@ func TestLocalStorageService(t *testing.T) {
 	panicIf(err)
 
 	// make a temp file for verification
-	retrievedfile, err := ioutil.TempFile("", "storagesvc_verify_")
+	retrievedfile, err := os.CreateTemp("", "storagesvc_verify_")
 	panicIf(err)
 	os.Remove(retrievedfile.Name())
 
@@ -238,9 +237,9 @@ func TestLocalStorageService(t *testing.T) {
 	defer os.Remove(retrievedfile.Name())
 
 	// compare contents
-	contents1, err := ioutil.ReadFile(tmpfile.Name())
+	contents1, err := os.ReadFile(tmpfile.Name())
 	panicIf(err)
-	contents2, err := ioutil.ReadFile(retrievedfile.Name())
+	contents2, err := os.ReadFile(retrievedfile.Name())
 	panicIf(err)
 	if !bytes.Equal(contents1, contents2) {
 		log.Panic("Contents don't match")