func extractTarGz()

in integration/create_server.go [140:193]
48 lines of code
13 McCabe index (conditional complexity)

func extractTarGz(src string) (string, error) {
	var rootPath string
	isRootDir := true

	file, err := os.Open(src)
	if err != nil {
		return "", fmt.Errorf("error opening archive file: %v", err.Error())
	}
	defer file.Close()

	reader, err := gzip.NewReader(file)
	if err != nil {
		return "", fmt.Errorf("error creating gzip reader: %v", err.Error())
	}

	tarReader := tar.NewReader(reader)
	for {
		header, err := tarReader.Next()
		if err == io.EOF {
			break
		}
		if err != nil {
			return "", fmt.Errorf("error reading from tar archive: %s", err.Error())
		}

		switch header.Typeflag {
		case tar.TypeDir:
			if isRootDir {
				rootPath = getRootFromPath(header.Name)
				isRootDir = false
			}
			if err := os.MkdirAll(header.Name, os.ModePerm); err != nil {
				return "", fmt.Errorf("mkdir failed: %s", err.Error())
			}
		case tar.TypeReg:
			if err = ensureBaseDir(header.Name); err != nil {
				return "", fmt.Errorf("error creating file from tar header: %s", err.Error())
			}
			outFile, err := os.Create(header.Name)
			if err != nil {
				return "", fmt.Errorf("error creating file from tar header: %s", err.Error())
			}

			if _, err = io.Copy(outFile, tarReader); err != nil {
				return "", fmt.Errorf("error copying file from archive: %s", err.Error())
			}
			outFile.Close()
		default:
			return "", fmt.Errorf("unknown header type detected while extracting from archive %s", src)
		}
	}

	return rootPath, nil
}