(cleanup) remove deprecated ioutil usage

The package has been deprecated. Cleaned up its usage.

Signed-off-by: Yaniv Kaul <yaniv.kaul@scylladb.com>

Author: mykaul

cluster.go

@@ -30,7 +30,6 @@ import (
 	"crypto/x509"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"os"
 	"sync/atomic"
@@ -656,7 +655,7 @@ func setupTLSConfig(sslOpts *SslOptions) (*tls.Config, error) {
 			tlsConfig.RootCAs = x509.NewCertPool()
 		}
 
-		pem, err := ioutil.ReadFile(sslOpts.CaPath)
+		pem, err := os.ReadFile(sslOpts.CaPath)
 		if err != nil {
 			return nil, fmt.Errorf("unable to open CA certs: %v", err)
 		}

conn.go

@@ -31,7 +31,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net"
 	"strconv"
 	"sync"
@@ -742,7 +741,7 @@ func (c *Conn) serve(ctx context.Context) {
 }
 
 func (c *Conn) discardFrame(head frm.FrameHeader) error {
-	_, err := io.CopyN(ioutil.Discard, c, int64(head.Length))
+	_, err := io.CopyN(io.Discard, c, int64(head.Length))
 	if err != nil {
 		return err
 	}

conn_test.go

@@ -37,7 +37,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"math/rand"
 	"net"
 	"os"
@@ -1200,7 +1199,7 @@ func NewSSLTestServer(t testing.TB, protocol uint8, ctx context.Context) *TestSe
 }
 
 func NewSSLTestServerWithSupportedFactory(t testing.TB, protocol uint8, ctx context.Context, supportedFactory testSupportedFactory) *TestServer {
-	pem, err := ioutil.ReadFile("testdata/pki/ca.crt")
+	pem, err := os.ReadFile("testdata/pki/ca.crt")
 	certPool := x509.NewCertPool()
 	if !certPool.AppendCertsFromPEM(pem) {
 		t.Fatalf("Failed parsing or appending certs")

frame.go

@@ -30,7 +30,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net"
 	"runtime"
 	"strconv"
@@ -364,7 +363,7 @@ func (f *framer) readFrame(r io.Reader, head *frm.FrameHeader) error {
 		return fmt.Errorf("frame body length can not be less than 0: %d", head.Length)
 	} else if head.Length > maxFrameSize {
 		// need to free up the connection to be used again
-		_, err := io.CopyN(ioutil.Discard, r, int64(head.Length))
+		_, err := io.CopyN(io.Discard, r, int64(head.Length))
 		if err != nil {
 			return fmt.Errorf("error whilst trying to discard frame with invalid length: %v", err)
 		}

framer_bench_test.go

@@ -29,7 +29,7 @@ package gocql
 
 import (
 	"compress/gzip"
-	"io/ioutil"
+	"io"
 	"os"
 	"testing"
 )
@@ -47,7 +47,7 @@ func readGzipData(path string) ([]byte, error) {
 	}
 	defer r.Close()
 
-	return ioutil.ReadAll(r)
+	return io.ReadAll(r)
 }
 
 func BenchmarkParseRowsFrame(b *testing.B) {

recreate_test.go

@@ -10,7 +10,7 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"regexp"
 	"sort"
 	"strings"
@@ -97,7 +97,7 @@ func TestRecreateSchema(t *testing.T) {
 			}
 			cleanup(t, session, test.Keyspace)
 
-			in, err := ioutil.ReadFile(test.Input)
+			in, err := os.ReadFile(test.Input)
 			if err != nil {
 				t.Fatal(err)
 			}
@@ -153,11 +153,11 @@ func TestRecreateSchema(t *testing.T) {
 				golden = []byte(trimSchema(string(golden)))
 			} else {
 				if *updateGolden {
-					if err := ioutil.WriteFile(test.Golden, []byte(dump), 0644); err != nil {
+					if err := os.WriteFile(test.Golden, []byte(dump), 0644); err != nil {
 						t.Fatal(err)
 					}
 				}
-				golden, err = ioutil.ReadFile(test.Golden)
+				golden, err = os.ReadFile(test.Golden)
 				if err != nil {
 					t.Fatal(err)
 				}
@@ -241,12 +241,12 @@ func TestScyllaEncryptionOptionsUnmarshaller(t *testing.T) {
 		golden = "testdata/recreate/scylla_encryption_options_golden.json"
 	)
 
-	inputBuf, err := ioutil.ReadFile(input)
+	inputBuf, err := os.ReadFile(input)
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	goldenBuf, err := ioutil.ReadFile(golden)
+	goldenBuf, err := os.ReadFile(golden)
 	if err != nil {
 		t.Fatal(err)
 	}