def _generate_layers(self, allow_missing_ids=False):
"""
Returns a generator of objects that have the blobSum and v1Compatibility keys in them,
starting from the base image and working toward the leaf node.
"""
for blob_sum_obj, history_obj in reversed(
list(
zip(
self._parsed[DOCKER_SCHEMA1_FS_LAYERS_KEY],
self._parsed[DOCKER_SCHEMA1_HISTORY_KEY],
)
)
):
try:
image_digest = digest_tools.Digest.parse_digest(
blob_sum_obj[DOCKER_SCHEMA1_BLOB_SUM_KEY]
)
except digest_tools.InvalidDigestException:
raise MalformedSchema1Manifest(
"could not parse manifest digest: %s"
% blob_sum_obj[DOCKER_SCHEMA1_BLOB_SUM_KEY]
)
metadata_string = history_obj[DOCKER_SCHEMA1_V1_COMPAT_KEY]
try:
v1_metadata = json.loads(metadata_string)
except (ValueError, TypeError):
raise MalformedSchema1Manifest(
"Could not parse metadata string: %s" % metadata_string
)
v1_metadata = v1_metadata or {}
container_config = v1_metadata.get("container_config") or {}
command_list = container_config.get("Cmd", None)
command = to_canonical_json(command_list) if command_list else None
if not allow_missing_ids and not "id" in v1_metadata:
raise MalformedSchema1Manifest("id field missing from v1Compatibility JSON")
labels = v1_metadata.get("config", {}).get("Labels", {}) or {}
extracted = Schema1V1Metadata(
image_id=v1_metadata.get("id"),
parent_image_id=v1_metadata.get("parent"),
created=v1_metadata.get("created"),
comment=v1_metadata.get("comment"),
author=v1_metadata.get("author"),
command=command,
labels=labels,
)
compressed_size = v1_metadata.get("Size")
yield Schema1Layer(
image_digest, extracted, metadata_string, compressed_size, False, None
)
def _updated_v1_metadata(v1_metadata_json, updated_id_map):
"""
Updates v1_metadata with new image IDs.
"""
parsed = json.loads(v1_metadata_json)
parsed["id"] = updated_id_map[parsed["id"]]
if parsed.get("parent") and parsed["parent"] in updated_id_map:
parsed["parent"] = updated_id_map[parsed["parent"]]
if parsed.get("container_config", {}).get("Image"):
existing_image = parsed["container_config"]["Image"]
if existing_image in updated_id_map:
parsed["container_config"]["image"] = updated_id_map[existing_image]
return to_canonical_json(parsed)
def test_to_canonical_json(input, expected_output):
result = to_canonical_json(input)
assert result == expected_output
# Ensure the result is utf-8.
assert isinstance(result, str)