use ioutil.ReadFile to release dependency of Go 1.16 (#217)

Signed-off-by: Sandy Xu <sandy@juicedata.io>

.github/workflows/test.yml

@@ -15,7 +15,7 @@ jobs:
     - name: Set up Go
       uses: actions/setup-go@v2
       with:
-        go-version: 1.16
+        go-version: 1.15
 
     - name: Test
       run: go test ./...
@@ -28,7 +28,7 @@ jobs:
     - name: Set up Go
       uses: actions/setup-go@v2
       with:
-        go-version: 1.16
+        go-version: 1.15
 
     - name: Test with race
       run: go test -race ./...
@@ -42,7 +42,7 @@ jobs:
       - name: Set up Go
         uses: actions/setup-go@v2
         with:
-          go-version: 1.16
+          go-version: 1.15
 
       - name: Lint
         uses: golangci/golangci-lint-action@v2

config/security.go

@@ -35,7 +35,7 @@ package config
 import (
 	"crypto/tls"
 	"crypto/x509"
-	"os"
+	"io/ioutil"
 
 	"github.com/pingcap/errors"
 )
@@ -64,7 +64,7 @@ func (s *Security) ToTLSConfig() (tlsConfig *tls.Config, err error) {
 		certPool := x509.NewCertPool()
 		// Create a certificate pool from the certificate authority
 		var ca []byte
-		ca, err = os.ReadFile(s.ClusterSSLCA)
+		ca, err = ioutil.ReadFile(s.ClusterSSLCA)
 		if err != nil {
 			err = errors.Errorf("could not read ca certificate: %s", err)
 			return

config/security_test.go

@@ -33,6 +33,7 @@
 package config
 
 import (
+	"io/ioutil"
 	"os"
 	"path/filepath"
 	"runtime"
@@ -47,8 +48,8 @@ func TestTLSConfig(t *testing.T) {
 	keyFile := filepath.Join(filepath.Dir(localFile), "key.pem")
 	perm := os.FileMode(0666)
 
-	assert.Nil(t, os.WriteFile(certFile, []byte(cert), perm))
-	assert.Nil(t, os.WriteFile(keyFile, []byte(key), perm))
+	assert.Nil(t, ioutil.WriteFile(certFile, []byte(cert), perm))
+	assert.Nil(t, ioutil.WriteFile(keyFile, []byte(key), perm))
 
 	security := Security{
 		ClusterSSLCA:   certFile,

examples/gcworker/go.mod

@@ -1,6 +1,6 @@
 module gcworker
 
-go 1.16
+go 1.15
 
 require github.com/tikv/client-go/v2 v2.0.0
 

examples/rawkv/go.mod

@@ -1,6 +1,6 @@
 module rawkv
 
-go 1.16
+go 1.15
 
 require github.com/tikv/client-go/v2 v2.0.0
 

examples/txnkv/go.mod

@@ -1,6 +1,6 @@
 module txnkv
 
-go 1.16
+go 1.15
 
 require github.com/tikv/client-go/v2 v2.0.0
 

go.mod

@@ -1,6 +1,6 @@
 module github.com/tikv/client-go/v2
 
-go 1.16
+go 1.15
 
 require (
 	github.com/cznic/mathutil v0.0.0-20181122101859-297441e03548