Merge branch 'jv-random-hex-helper' into 'master'

Add text.RandomHex helper

See merge request gitlab-org/gitaly!1322

4 files changed, 24 insertions, 15 deletions

diff --git a/internal/git/objectpool/fetch_test.go b/internal/git/objectpool/fetch_test.go
index 5af01b220..6b4e94463 100644
--- a/internal/git/objectpool/fetch_test.go
+++ b/internal/git/objectpool/fetch_test.go
@@ -1,10 +1,7 @@
 package objectpool
 
 import (
-	"crypto/rand"
-	"encoding/hex"
 	"fmt"
-	"io"
 	"io/ioutil"
 	"path/filepath"
 	"strings"
@@ -36,10 +33,8 @@ func TestFetchFromOriginDangling(t *testing.T) {
 
 	// We want to have some objects that are guaranteed to be dangling. Use
 	// random data to make each object unique.
-	nonceBytes := make([]byte, 4)
-	_, err = io.ReadFull(rand.Reader, nonceBytes)
+	nonce, err := text.RandomHex(4)
 	require.NoError(t, err)
-	nonce := hex.EncodeToString(nonceBytes)
 
 	baseArgs := []string{"-C", pool.FullPath()}
 
diff --git a/internal/helper/text/random.go b/internal/helper/text/random.go
new file mode 100644
index 000000000..5b9f9a714
--- /dev/null
+++ b/internal/helper/text/random.go
@@ -0,0 +1,17 @@
+package text
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"io"
+)
+
+// RandomHex returns an n-byte hexademical random string.
+func RandomHex(n int) (string, error) {
+	buf := make([]byte, n)
+	if _, err := io.ReadFull(rand.Reader, buf); err != nil {
+		return "", err
+	}
+
+	return hex.EncodeToString(buf), nil
+}
diff --git a/internal/service/objectpool/alternates.go b/internal/service/objectpool/alternates.go
index 7e952993c..332c7a2e5 100644
--- a/internal/service/objectpool/alternates.go
+++ b/internal/service/objectpool/alternates.go
@@ -2,10 +2,8 @@ package objectpool
 
 import (
 	"context"
-	"crypto/rand"
 	"errors"
 	"fmt"
-	"io"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -17,6 +15,7 @@ import (
 	"gitlab.com/gitlab-org/gitaly-proto/go/gitalypb"
 	"gitlab.com/gitlab-org/gitaly/internal/git"
 	"gitlab.com/gitlab-org/gitaly/internal/helper"
+	"gitlab.com/gitlab-org/gitaly/internal/helper/text"
 )
 
 // DisconnectGitAlternates is a slightly dangerous RPC. It optimistically
@@ -109,12 +108,12 @@ func disconnectAlternates(ctx context.Context, repo *gitalypb.Repository) error
 }
 
 func newBackupFile(altFile string) (string, error) {
-	randSuffix := make([]byte, 6)
-	if _, err := io.ReadFull(rand.Reader, randSuffix); err != nil {
+	randSuffix, err := text.RandomHex(6)
+	if err != nil {
 		return "", err
 	}
 
-	return fmt.Sprintf("%s.%d.%x", altFile, time.Now().Unix(), randSuffix), nil
+	return fmt.Sprintf("%s.%d.%s", altFile, time.Now().Unix(), randSuffix), nil
 }
 
 func findObjectFiles(altDir string) ([]string, error) {
diff --git a/internal/testhelper/testhelper.go b/internal/testhelper/testhelper.go
index 2ff9c0a3f..fcd7db736 100644
--- a/internal/testhelper/testhelper.go
+++ b/internal/testhelper/testhelper.go
@@ -3,7 +3,6 @@ package testhelper
 import (
 	"bytes"
 	"context"
-	"crypto/rand"
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
@@ -482,11 +481,10 @@ func AssertFileNotExists(t *testing.T, path string) {
 
 // NewTestObjectPoolName returns a random pool repository name.
 func NewTestObjectPoolName(t *testing.T) string {
-	b := make([]byte, 5)
-	_, err := io.ReadFull(rand.Reader, b)
+	b, err := text.RandomHex(5)
 	require.NoError(t, err)
 
-	return fmt.Sprintf("pool-%x.git", b)
+	return fmt.Sprintf("pool-%s.git", b)
 }
 
 // CreateLooseRef creates a ref that points to master