func tarFile()

in pkg/3p/archiver/tar.go [127:184]
47 lines of code
14 McCabe index (conditional complexity)

func tarFile(tarWriter *tar.Writer, source, dest string) error {
	sourceInfo, err := os.Stat(source)
	if err != nil {
		return fmt.Errorf("%s: stat: %v", source, err)
	}

	var baseDir string
	if sourceInfo.IsDir() {
		baseDir = filepath.Base(source)
	}

	return filepath.Walk(source, func(path string, info os.FileInfo, err error) error {
		if err != nil {
			return fmt.Errorf("error walking to %s: %v", path, err)
		}

		header, err := tar.FileInfoHeader(info, path)
		if err != nil {
			return fmt.Errorf("%s: making header: %v", path, err)
		}

		if baseDir != "" {
			header.Name = filepath.ToSlash(filepath.Join(baseDir, strings.TrimPrefix(path, source)))
		}

		if header.Name == dest {
			// our new tar file is inside the directory being archived; skip it
			return nil
		}

		if info.IsDir() {
			header.Name += "/"
		}

		err = tarWriter.WriteHeader(header)
		if err != nil {
			return fmt.Errorf("%s: writing header: %v", path, err)
		}

		if info.IsDir() {
			return nil
		}

		if header.Typeflag == tar.TypeReg {
			file, err := os.Open(path)
			if err != nil {
				return fmt.Errorf("%s: open: %v", path, err)
			}
			defer file.Close()

			_, err = io.CopyN(tarWriter, file, info.Size())
			if err != nil && err != io.EOF {
				return fmt.Errorf("%s: copying contents: %v", path, err)
			}
		}
		return nil
	})
}