safe-rename.go

package filesystem

import (
	"io"
	"os"
)

func SafeRenameFile(src, dst string) error {
	if err := CopyFile(src, dst); err != nil {
		return err
	}
	return os.Remove(src)
}

// credit https://gist.github.com/r0l1/92462b38df26839a3ca324697c8cba04
func CopyFile(src, dst string) (err error) {
	in, err := os.Open(src)
	if err != nil {
		return
	}
	defer in.Close()

	out, err := os.Create(dst)
	if err != nil {
		return
	}
	defer func() {
		if e := out.Close(); e != nil {
			err = e
		}
	}()

	_, err = io.Copy(out, in)
	if err != nil {
		return
	}

	err = out.Sync()
	if err != nil {
		return
	}

	si, err := os.Stat(src)
	if err != nil {
		return
	}
	err = os.Chmod(dst, si.Mode())
	if err != nil {
		return
	}

	return
}