func extractEmbeddedLayer(file *os.File, layerID string, outputPath string) (*os.File, error) {
util.Info("Extracting layer: ", layerID, "\n")
_, err := file.Seek(0, 0)
if err != nil {
fmt.Errorf("error seeking file: %v", err)
}
layerTarPath := path.Join(layerID, "layer.tar")
var layerFile *os.File
fileWalker := func(t *tarball.TarFile) error {
if filepath.Clean(t.Name()) == layerTarPath {
layerFile, err = os.Create(outputPath)
if err != nil {
return fmt.Errorf("error creating layer: %v", err)
}
_, err = io.Copy(layerFile, t.TarStream)
if err != nil {
return fmt.Errorf("error getting layer: %v", err)
}
}
return nil
}
tr := tar.NewReader(file)
if err := tarball.Walk(*tr, fileWalker); err != nil {
return nil, err
}
if layerFile == nil {
return nil, fmt.Errorf("file %q not found", layerTarPath)
}
return layerFile, nil
}
func getLayer(imgID, registry string, repoData *RepoData, imgSize int64) (io.ReadCloser, error) {
client := &http.Client{}
req, err := http.NewRequest("GET", "https://"+path.Join(registry, "images", imgID, "layer"), nil)
if err != nil {
return nil, err
}
setAuthToken(req, repoData.Tokens)
setCookie(req, repoData.Cookie)
util.Info("Downloading layer: ", imgID, "\n")
res, err := client.Do(req)
if err != nil {
return nil, err
}
if res.StatusCode != 200 {
res.Body.Close()
return nil, fmt.Errorf("HTTP code: %d. URL: %s", res.StatusCode, req.URL)
}
return res.Body, nil
}