rename disk.OpenFile to Open which will do os.Open (which will be read-only). disk.OpenFile will do os.OpenFile (which can be rw, append)

pkg/donut/disk/disk.go

@@ -170,8 +170,8 @@ func (disk Disk) CreateFile(filename string) (*atomic.File, error) {
 	return f, nil
 }
 
-// OpenFile - read a file inside disk root path
-func (disk Disk) OpenFile(filename string) (*os.File, error) {
+// Open - read a file inside disk root path
+func (disk Disk) Open(filename string) (*os.File, error) {
 	disk.lock.Lock()
 	defer disk.lock.Unlock()
 
@@ -185,6 +185,21 @@ func (disk Disk) OpenFile(filename string) (*os.File, error) {
 	return dataFile, nil
 }
 
+// OpenFile - Use with caution
+func (disk Disk) OpenFile(filename string, flags int, perm os.FileMode) (*os.File, error) {
+	disk.lock.Lock()
+	defer disk.lock.Unlock()
+
+	if filename == "" {
+		return nil, iodine.New(InvalidArgument{}, nil)
+	}
+	dataFile, err := os.OpenFile(filepath.Join(disk.path, filename), flags, perm)
+	if err != nil {
+		return nil, iodine.New(err, nil)
+	}
+	return dataFile, nil
+}
+
 // formatBytes - Convert bytes to human readable string. Like a 2 MB, 64.2 KB, 52 B
 func formatBytes(i int64) (result string) {
 	switch {

pkg/donut/disk/disk_test.go

@@ -65,19 +65,19 @@ func (s *MyDiskSuite) TestDiskCreateFile(c *C) {
 	// close renames the file
 	f.Close()
 
-	// Openfile should be a success
-	_, err = s.disk.OpenFile("hello1")
+	// Open should be a success
+	_, err = s.disk.Open("hello1")
 	c.Assert(err, IsNil)
 }
 
-func (s *MyDiskSuite) TestDiskOpenFile(c *C) {
+func (s *MyDiskSuite) TestDiskOpen(c *C) {
 	f1, err := s.disk.CreateFile("hello2")
 	c.Assert(err, IsNil)
 	c.Assert(f1.Name(), Not(Equals), filepath.Join(s.path, "hello2"))
 	// close renames the file
 	f1.Close()
 
-	f2, err := s.disk.OpenFile("hello2")
+	f2, err := s.disk.Open("hello2")
 	c.Assert(err, IsNil)
 	c.Assert(f2.Name(), Equals, filepath.Join(s.path, "hello2"))
 	defer f2.Close()