art: Move from io/ioutil to io and os packages (#470)

refactor: move from io/ioutil to io and os packages

The io/ioutil package has been deprecated as of Go 1.16 [1]. This commit
replaces the existing io/ioutil functions with their new definitions in
io and os packages.

[1]: https://golang.org/doc/go1.16#ioutil
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>

internal/agent/agent.go

@@ -2,7 +2,6 @@ package agent
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 
@@ -46,7 +45,7 @@ func Run(opts ...Option) error {
 
 	// Create if not exist
 	if _, err := os.Stat(fileName); err != nil {
-		err = ioutil.WriteFile(fileName, []byte{}, os.ModePerm)
+		err = os.WriteFile(fileName, []byte{}, os.ModePerm)
 		if err != nil {
 			return err
 		}

internal/agent/config.go

@@ -1,7 +1,7 @@
 package agent
 
 import (
-	"io/ioutil"
+	"os"
 
 	"github.com/kairos-io/kairos/internal/kairos"
 
@@ -29,35 +29,35 @@ func LoadConfig(path ...string) (*Config, error) {
 	cfg := &Config{}
 
 	for _, p := range path {
-		f, err := ioutil.ReadFile(p)
+		f, err := os.ReadFile(p)
 		if err == nil {
 			yaml.Unmarshal(f, cfg) //nolint:errcheck
 		}
 	}
 
 	if cfg.Branding.InteractiveInstall == "" {
-		f, err := ioutil.ReadFile(kairos.BrandingFile("interactive_install_text"))
+		f, err := os.ReadFile(kairos.BrandingFile("interactive_install_text"))
 		if err == nil {
 			cfg.Branding.InteractiveInstall = string(f)
 		}
 	}
 
 	if cfg.Branding.Install == "" {
-		f, err := ioutil.ReadFile(kairos.BrandingFile("install_text"))
+		f, err := os.ReadFile(kairos.BrandingFile("install_text"))
 		if err == nil {
 			cfg.Branding.Install = string(f)
 		}
 	}
 
 	if cfg.Branding.Recovery == "" {
-		f, err := ioutil.ReadFile(kairos.BrandingFile("recovery_text"))
+		f, err := os.ReadFile(kairos.BrandingFile("recovery_text"))
 		if err == nil {
 			cfg.Branding.Recovery = string(f)
 		}
 	}
 
 	if cfg.Branding.Reset == "" {
-		f, err := ioutil.ReadFile(kairos.BrandingFile("reset_text"))
+		f, err := os.ReadFile(kairos.BrandingFile("reset_text"))
 		if err == nil {
 			cfg.Branding.Reset = string(f)
 		}

internal/agent/install.go

@@ -4,7 +4,6 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"syscall"
@@ -40,7 +39,7 @@ func optsToArgs(options map[string]string) (res []string) {
 }
 
 func ManualInstall(config string, options map[string]string) error {
-	dat, err := ioutil.ReadFile(config)
+	dat, err := os.ReadFile(config)
 	if err != nil {
 		return err
 	}
@@ -195,7 +194,7 @@ func RunInstall(options map[string]string) error {
 	utils.SH("elemental run-stage kairos-install.pre")             //nolint:errcheck
 	events.RunHookScript("/usr/bin/kairos-agent.install.pre.hook") //nolint:errcheck
 
-	f, _ := ioutil.TempFile("", "xxxx")
+	f, _ := os.CreateTemp("", "xxxx")
 	defer os.RemoveAll(f.Name())
 
 	device, ok := options["device"]
@@ -232,7 +231,7 @@ func RunInstall(options map[string]string) error {
 	env := append(c.Install.Env, c.Env...)
 	utils.SetEnv(env)
 
-	err := ioutil.WriteFile(f.Name(), []byte(cloudInit), os.ModePerm)
+	err := os.WriteFile(f.Name(), []byte(cloudInit), os.ModePerm)
 	if err != nil {
 		fmt.Printf("could not write cloud init: %s\n", err.Error())
 		os.Exit(1)

internal/cmd/utils.go

@@ -2,7 +2,6 @@ package cmd
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 
 	"github.com/kairos-io/kairos/internal/kairos"
@@ -19,7 +18,7 @@ func PrintText(f string, banner string) {
 func PrintBranding(b []byte) {
 	brandingFile := kairos.BrandingFile("banner")
 	if _, err := os.Stat(brandingFile); err == nil {
-		f, err := ioutil.ReadFile(brandingFile)
+		f, err := os.ReadFile(brandingFile)
 		if err == nil {
 			fmt.Println(string(f))
 		}