Move some generic funcs into fileutil.go

Author: mgatny

filestore.go

@@ -75,35 +75,6 @@ func newFileStore(sessionID SessionID, dirname string) (*fileStore, error) {
 	return store, nil
 }
 
-func closeFile(f *os.File) error {
-	if f != nil {
-		if err := f.Close(); err != nil {
-			if !os.IsNotExist(err) {
-				return err
-			}
-		}
-	}
-	return nil
-}
-
-func removeFile(fname string) error {
-	err := os.Remove(fname)
-	if (err != nil) && !os.IsNotExist(err) {
-		return err
-	}
-	return nil
-}
-
-// openOrCreateFile opens a file for reading and writing, creating it if necessary
-func openOrCreateFile(fname string, perm os.FileMode) (f *os.File, err error) {
-	if f, err = os.OpenFile(fname, os.O_RDWR, perm); err != nil {
-		if f, err = os.OpenFile(fname, os.O_RDWR|os.O_CREATE, perm); err != nil {
-			return nil, fmt.Errorf("error opening or creating file: %s: %s", fname, err.Error())
-		}
-	}
-	return f, nil
-}
-
 // Reset deletes the store files and sets the seqnums back to 1
 func (store *fileStore) Reset() error {
 	store.cache.Reset()

fileutil.go

@@ -1,6 +1,10 @@
 package quickfix
 
-import "strings"
+import (
+	"fmt"
+	"os"
+	"strings"
+)
 
 func sessionIDFilenamePrefix(s SessionID) string {
 	sender := []string{s.SenderCompID}
@@ -25,3 +29,34 @@ func sessionIDFilenamePrefix(s SessionID) string {
 	}
 	return strings.Join(fname, "-")
 }
+
+// closeFile behaves like Close, except that no error is returned if the file does not exist
+func closeFile(f *os.File) error {
+	if f != nil {
+		if err := f.Close(); err != nil {
+			if !os.IsNotExist(err) {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+// removeFile behaves like os.Remove, except that no error is returned if the file does not exist
+func removeFile(fname string) error {
+	err := os.Remove(fname)
+	if (err != nil) && !os.IsNotExist(err) {
+		return err
+	}
+	return nil
+}
+
+// openOrCreateFile opens a file for reading and writing, creating it if necessary
+func openOrCreateFile(fname string, perm os.FileMode) (f *os.File, err error) {
+	if f, err = os.OpenFile(fname, os.O_RDWR, perm); err != nil {
+		if f, err = os.OpenFile(fname, os.O_RDWR|os.O_CREATE, perm); err != nil {
+			return nil, fmt.Errorf("error opening or creating file: %s: %s", fname, err.Error())
+		}
+	}
+	return f, nil
+}

fileutil_test.go

@@ -1,11 +1,25 @@
 package quickfix
 
 import (
+	"fmt"
+	"os"
+	"path"
 	"testing"
 
 	"github.com/stretchr/testify/require"
 )
 
+func requireNotFileExists(t *testing.T, fname string) {
+	_, err := os.Stat(fname)
+	require.NotNil(t, err)
+	require.True(t, os.IsNotExist(err))
+}
+
+func requireFileExists(t *testing.T, fname string) {
+	_, err := os.Stat(fname)
+	require.Nil(t, err)
+}
+
 func TestSessionIDFilename_MinimallyQualifiedSessionID(t *testing.T) {
 	// When the session ID is
 	sessionID := SessionID{BeginString: "FIX.4.4", SenderCompID: "SENDER", TargetCompID: "TARGET"}
@@ -30,3 +44,22 @@ func TestSessionIDFilename_FullyQualifiedSessionID(t *testing.T) {
 	// Then the filename should be
 	require.Equal(t, "FIX.4.4-A_B_C-D_E_F-G", sessionIDFilenamePrefix(sessionID))
 }
+
+func TestOpenOrCreateFile(t *testing.T) {
+	// When the file doesn't exist yet
+	fname := path.Join(os.TempDir(), fmt.Sprintf("TestOpenOrCreateFile-%d", os.Getpid()))
+	requireNotFileExists(t, fname)
+	defer os.Remove(fname)
+
+	// Then it should be created
+	f, err := openOrCreateFile(fname, 0664)
+	requireFileExists(t, fname)
+
+	// When the file already exists
+	f.Close()
+
+	// Then it should be opened
+	f, err = openOrCreateFile(fname, 0664)
+	require.Nil(t, err)
+	require.Nil(t, f.Close())
+}