Function ExtractDockerArchive

cmd/nerdctl/helpers/testing.go:38–73

(archiveTarPath, rootfsPath string)

}

func ExtractDockerArchive(archiveTarPath, rootfsPath string) error {
	if err := os.MkdirAll(rootfsPath, 0755); err != nil {
		return err
	}
	workDir, err := os.MkdirTemp("", "extract-docker-archive")
	if err != nil {
		return err
	}
	defer os.RemoveAll(workDir)
	if err := ExtractTarFile(workDir, archiveTarPath); err != nil {
		return err
	}
	manifestJSONPath := filepath.Join(workDir, "manifest.json")
	manifestJSONBytes, err := os.ReadFile(manifestJSONPath)
	if err != nil {
		return err
	}
	var mani DockerArchiveManifestJSON
	if err := json.Unmarshal(manifestJSONBytes, &mani); err != nil {
		return err
	}
	if len(mani) > 1 {
		return fmt.Errorf("multi-image archive cannot be extracted: contains %d images", len(mani))
	}
	if len(mani) < 1 {
		return errors.New("invalid archive")
	}
	ent := mani[0]
	for _, l := range ent.Layers {
		layerTarPath := filepath.Join(workDir, l)
		if err := ExtractTarFile(rootfsPath, layerTarPath); err != nil {
			return err
		}
	}
	return nil
}

type DockerArchiveManifestJSON []DockerArchiveManifestJSONEntry