chore: replace deprecated ioutil methods (flant#444)

Signed-off-by: Ivan Mikheykin <[email protected]>

.golangci.yaml

@@ -1,6 +1,11 @@
 run:
   timeout: 15m
+linters:
+  include:
+    - bodyclose
+    - asciicheck
+    - dogsled
+    - durationcheck
 issues:
-  exclude:
-  - ST1005.*
-  - SA1019.* # "io/ioutil" has been deprecated since Go 1.16
+  max-issues-per-linter: 0
+  max-same-issues: 0

pkg/hook/hook.go

@@ -3,7 +3,6 @@ package hook
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path"
 	"path/filepath"
@@ -83,7 +82,7 @@ func (h *Hook) WithHookController(hookController controller.HookController) {
 	h.HookController = hookController
 }
 
-func (h *Hook) Run(bindingType BindingType, context []BindingContext, logLabels map[string]string) (*HookResult, error) {
+func (h *Hook) Run(_ BindingType, context []BindingContext, logLabels map[string]string) (*HookResult, error) {
 	// Refresh snapshots
 	freshBindingContext := h.HookController.UpdateSnapshots(context)
 
@@ -117,15 +116,15 @@ func (h *Hook) Run(bindingType BindingType, context []BindingContext, logLabels
 	// remove tmp file on hook exit
 	defer func() {
 		if app.DebugKeepTmpFiles != "yes" {
-			os.Remove(contextPath)
-			os.Remove(metricsPath)
-			os.Remove(conversionPath)
-			os.Remove(validatingPath)
-			os.Remove(kubernetesPatchPath)
+			_ = os.Remove(contextPath)
+			_ = os.Remove(metricsPath)
+			_ = os.Remove(conversionPath)
+			_ = os.Remove(validatingPath)
+			_ = os.Remove(kubernetesPatchPath)
 		}
 	}()
 
-	envs := []string{}
+	envs := make([]string, 0)
 	envs = append(envs, os.Environ()...)
 	if contextPath != "" {
 		envs = append(envs, fmt.Sprintf("BINDING_CONTEXT_PATH=%s", contextPath))
@@ -159,7 +158,7 @@ func (h *Hook) Run(bindingType BindingType, context []BindingContext, logLabels
 		return result, fmt.Errorf("got bad conversion response: %s", err)
 	}
 
-	result.KubernetesPatchBytes, err = ioutil.ReadFile(kubernetesPatchPath)
+	result.KubernetesPatchBytes, err = os.ReadFile(kubernetesPatchPath)
 	if err != nil {
 		return result, fmt.Errorf("can't read object patch file: %s", err)
 	}
@@ -172,7 +171,7 @@ func (h *Hook) SafeName() string {
 }
 
 func (h *Hook) GetConfigDescription() string {
-	msgs := []string{}
+	msgs := make([]string, 0)
 	if h.Config.OnStartup != nil {
 		msgs = append(msgs, fmt.Sprintf("OnStartup:%d", int64(h.Config.OnStartup.Order)))
 	}
@@ -246,7 +245,7 @@ func (h *Hook) prepareBindingContextJsonFile(context BindingContextList) (string
 
 	bindingContextPath := filepath.Join(h.TmpDir, fmt.Sprintf("hook-%s-binding-context-%s.json", h.SafeName(), uuid.NewV4().String()))
 
-	err = ioutil.WriteFile(bindingContextPath, data, 0644)
+	err = os.WriteFile(bindingContextPath, data, 0644)
 	if err != nil {
 		return "", err
 	}
@@ -257,7 +256,7 @@ func (h *Hook) prepareBindingContextJsonFile(context BindingContextList) (string
 func (h *Hook) prepareMetricsFile() (string, error) {
 	metricsPath := filepath.Join(h.TmpDir, fmt.Sprintf("hook-%s-metrics-%s.json", h.SafeName(), uuid.NewV4().String()))
 
-	err := ioutil.WriteFile(metricsPath, []byte{}, 0644)
+	err := os.WriteFile(metricsPath, []byte{}, 0644)
 	if err != nil {
 		return "", err
 	}
@@ -268,7 +267,7 @@ func (h *Hook) prepareMetricsFile() (string, error) {
 func (h *Hook) prepareValidatingResponseFile() (string, error) {
 	validatingPath := filepath.Join(h.TmpDir, fmt.Sprintf("hook-%s-validating-response-%s.json", h.SafeName(), uuid.NewV4().String()))
 
-	err := ioutil.WriteFile(validatingPath, []byte{}, 0644)
+	err := os.WriteFile(validatingPath, []byte{}, 0644)
 	if err != nil {
 		return "", err
 	}
@@ -279,7 +278,7 @@ func (h *Hook) prepareValidatingResponseFile() (string, error) {
 func (h *Hook) prepareConversionResponseFile() (string, error) {
 	conversionPath := filepath.Join(h.TmpDir, fmt.Sprintf("hook-%s-conversion-response-%s.json", h.SafeName(), uuid.NewV4().String()))
 
-	err := ioutil.WriteFile(conversionPath, []byte{}, 0644)
+	err := os.WriteFile(conversionPath, []byte{}, 0644)
 	if err != nil {
 		return "", err
 	}
@@ -288,9 +287,9 @@ func (h *Hook) prepareConversionResponseFile() (string, error) {
 }
 
 func CreateRateLimiter(cfg *config.HookConfig) *rate.Limiter {
-	// Create rate limiter
-	limit := rate.Inf // no rate limit by default
-	burst := 1        // no more then 1 event at time
+	// Create rate limiter.
+	limit := rate.Inf // No rate limit by default.
+	burst := 1        // No more than 1 event at time.
 	if cfg.Settings != nil {
 		if cfg.Settings.ExecutionMinInterval != 0 {
 			limit = rate.Every(cfg.Settings.ExecutionMinInterval)
@@ -305,7 +304,7 @@ func CreateRateLimiter(cfg *config.HookConfig) *rate.Limiter {
 func (h *Hook) prepareObjectPatchFile() (string, error) {
 	objectPatchPath := filepath.Join(h.TmpDir, fmt.Sprintf("%s-object-patch-%s", h.SafeName(), uuid.NewV4().String()))
 
-	err := ioutil.WriteFile(objectPatchPath, []byte{}, 0644)
+	err := os.WriteFile(objectPatchPath, []byte{}, 0644)
 	if err != nil {
 		return "", err
 	}

pkg/kube/object_patch/patch_test.go

@@ -3,7 +3,7 @@ package object_patch
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"testing"
 
 	"github.com/flant/kube-client/fake"
@@ -18,7 +18,7 @@ import (
 
 func mustReadFile(t *testing.T, filePath string) []byte {
 	t.Helper()
-	content, err := ioutil.ReadFile(filePath)
+	content, err := os.ReadFile(filePath)
 	require.NoError(t, err)
 	return content
 }

pkg/metric_storage/operation/operation.go

@@ -5,7 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
+	"os"
 	"strings"
 
 	"github.com/hashicorp/go-multierror"
@@ -89,7 +89,7 @@ func MetricOperationsFromBytes(data []byte) ([]MetricOperation, error) {
 }
 
 func MetricOperationsFromFile(filePath string) ([]MetricOperation, error) {
-	data, err := ioutil.ReadFile(filePath)
+	data, err := os.ReadFile(filePath)
 	if err != nil {
 		return nil, fmt.Errorf("cannot read %s: %s", filePath, err)
 	}

pkg/utils/checksum/checksum.go

@@ -3,7 +3,6 @@ package checksum
 import (
 	"crypto/md5"
 	"encoding/hex"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"sort"
@@ -19,7 +18,7 @@ func CalculateChecksum(stringArr ...string) string {
 }
 
 func CalculateChecksumOfFile(path string) (string, error) {
-	content, err := ioutil.ReadFile(path)
+	content, err := os.ReadFile(path)
 	if err != nil {
 		return "", err
 	}

pkg/webhook/conversion/handler.go

@@ -3,7 +3,7 @@ package conversion
 import (
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"strings"
 
@@ -41,7 +41,7 @@ func NewWebhookHandler() *WebhookHandler {
 func (h *WebhookHandler) ServeReviewRequest(w http.ResponseWriter, r *http.Request) {
 	defer r.Body.Close()
 
-	bodyBytes, err := ioutil.ReadAll(r.Body)
+	bodyBytes, err := io.ReadAll(r.Body)
 	if err != nil {
 		w.WriteHeader(http.StatusInternalServerError)
 		_, _ = w.Write([]byte("Error reading request body"))

pkg/webhook/conversion/manager.go

@@ -1,7 +1,7 @@
 package conversion
 
 import (
-	"io/ioutil"
+	"os"
 
 	log "github.com/sirupsen/logrus"
 
@@ -14,14 +14,15 @@ type EventHandlerFn func(event Event) (*Response, error)
 // WebhookManager is a public interface to be used from operator.go.
 //
 // No dynamic configuration for now. The steps are:
-//   - Init():
-//     - Create a router to distinguish conversion requests between CRDs
-//     - Create a handler to handle ConversionReview
-//     - Create a server that listens for Kubernetes requests
+// - Init():
+//   - Create a router to distinguish conversion requests between CRDs
+//   - Create a handler to handle ConversionReview
+//   - Create a server that listens for Kubernetes requests
 //   - Call AddWebhook() to register a CRD name in conversion bindings in hooks
-//   - Start():
-//     - Start server loop.
-//     - Update clientConfig in each registered CRD.
+//
+// - Start():
+//   - Start server loop.
+//   - Update clientConfig in each registered CRD.
 type WebhookManager struct {
 	KubeClient klient.Client
 
@@ -45,7 +46,7 @@ func (m *WebhookManager) Init() error {
 	log.Info("Initialize conversion webhooks manager. Load certificates.")
 
 	// settings
-	caBundleBytes, err := ioutil.ReadFile(m.Settings.CAPath)
+	caBundleBytes, err := os.ReadFile(m.Settings.CAPath)
 	if err != nil {
 		return err
 	}

pkg/webhook/conversion/response.go

@@ -5,25 +5,30 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
+	"os"
 	"strconv"
 	"strings"
 
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 )
 
 /*
+Response is a holder of the conversion hook response.
+
+Unlike ConverionsResponse, only one filed (FailedMessage) is used to determine success or fail:
+
+Response is Success if FailedMessage is empty:
+
+	"result": {
+	  "status": "Success"
+	},
 
-FailedMessage:
-Response is Success if empty string:
-"result": {
-  "status": "Success"
-},
 Response is Failed:
-"result": {
-  "status": "Failed",
-  "message": FailedMessage
-}
+
+	"result": {
+	  "status": "Failed",
+	  "message": FailedMessage
+	}
 
 ConvertedObjects:
 # Objects must match the order of request.objects, and have apiVersion set to <request.desiredAPIVersion>.
@@ -37,7 +42,7 @@ type Response struct {
 }
 
 func ResponseFromFile(filePath string) (*Response, error) {
-	data, err := ioutil.ReadFile(filePath)
+	data, err := os.ReadFile(filePath)
 	if err != nil {
 		return nil, fmt.Errorf("cannot read %s: %s", filePath, err)
 	}

pkg/webhook/server/server.go

@@ -4,7 +4,6 @@ import (
 	"crypto/tls"
 	"crypto/x509"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"os"
@@ -48,7 +47,7 @@ func (s *WebhookServer) Start() error {
 		roots := x509.NewCertPool()
 
 		for _, caPath := range s.Settings.ClientCAPaths {
-			caBytes, err := ioutil.ReadFile(caPath)
+			caBytes, err := os.ReadFile(caPath)
 			if err != nil {
 				return fmt.Errorf("load client CA '%s': %v", caPath, err)
 			}

pkg/webhook/server/server_test.go

@@ -2,7 +2,7 @@ package server
 
 import (
 	"crypto/x509"
-	"io/ioutil"
+	"os"
 	"testing"
 
 	"github.com/go-chi/chi/v5"
@@ -36,7 +36,7 @@ func Test_Client_CA(t *testing.T) {
 	}
 
 	for _, caPath := range s.ClientCAPaths {
-		caBytes, err := ioutil.ReadFile(caPath)
+		caBytes, err := os.ReadFile(caPath)
 		if err != nil {
 			t.Fatalf("ca '%s' should be read: %v", caPath, err)
 		}

pkg/webhook/validating/handler.go

@@ -3,7 +3,7 @@ package validating
 import (
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"strings"
 
@@ -39,7 +39,7 @@ func NewWebhookHandler() *WebhookHandler {
 func (h *WebhookHandler) ServeReviewRequest(w http.ResponseWriter, r *http.Request) {
 	defer r.Body.Close()
 
-	bodyBytes, err := ioutil.ReadAll(r.Body)
+	bodyBytes, err := io.ReadAll(r.Body)
 	if err != nil {
 		w.WriteHeader(http.StatusInternalServerError)
 		_, _ = w.Write([]byte("Error reading request body"))
@@ -130,7 +130,7 @@ func (h *WebhookHandler) HandleReviewRequest(path string, body []byte) (*v1.Admi
 // DetectConfigurationAndWebhook extracts configurationID and a webhookID from the url path.
 func DetectConfigurationAndWebhook(path string) (configurationID string, webhookID string) {
 	parts := strings.Split(path, "/")
-	webhookParts := []string{}
+	webhookParts := make([]string, 0)
 	for _, p := range parts {
 		if p == "" {
 			continue

pkg/webhook/validating/manager.go

@@ -1,7 +1,7 @@
 package validating
 
 import (
-	"io/ioutil"
+	"os"
 
 	log "github.com/sirupsen/logrus"
 
@@ -60,7 +60,7 @@ func (m *WebhookManager) Init() error {
 		m.DefaultConfigurationId = DefaultConfigurationId
 	}
 	// settings
-	caBundleBytes, err := ioutil.ReadFile(m.Settings.CAPath)
+	caBundleBytes, err := os.ReadFile(m.Settings.CAPath)
 	if err != nil {
 		return err
 	}

pkg/webhook/validating/types/response.go

@@ -5,7 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
+	"os"
 	"strconv"
 	"strings"
 )
@@ -17,7 +17,7 @@ type ValidatingResponse struct {
 }
 
 func ValidatingResponseFromFile(filePath string) (*ValidatingResponse, error) {
-	data, err := ioutil.ReadFile(filePath)
+	data, err := os.ReadFile(filePath)
 	if err != nil {
 		return nil, fmt.Errorf("cannot read %s: %s", filePath, err)
 	}