diff options
| -rw-r--r-- | src/virtBootstrap/sources.py | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/src/virtBootstrap/sources.py b/src/virtBootstrap/sources.py index 78f6be3..9d675cb 100644 --- a/src/virtBootstrap/sources.py +++ b/src/virtBootstrap/sources.py @@ -360,6 +360,28 @@ class DockerSource(object): # Remove the manifest file as it is not needed os.remove(os.path.join(self.images_dir, "manifest.json")) + def validate_image_layers(self): + """ + Check if layers of container image exist in image_dir + and have valid hash sum. + """ + for sum_type, sum_expected, path, _ignore in self.layers: + logger.debug("Checking layer: %s", path) + if not (os.path.exists(path) + and checksum(path, sum_type, sum_expected)): + return False + return True + + def fetch_layers(self): + """ + Retrieve layers of container image. + """ + # Check if layers have been downloaded + if self.validate_image_layers(): + logger.info("Using cached image layers") + else: + self.download_image() + def unpack(self, dest): """ Extract image files from Docker image @@ -370,7 +392,7 @@ class DockerSource(object): # Layers are in order - root layer first # Reference: # https://github.com/containers/image/blob/master/image/oci.go#L100 - self.download_image() + self.fetch_layers() # Unpack to destination directory if self.output_format == 'dir': |