def write_version(self, version_uid: VersionUid, data: str, overwrite: Optional[bool] = False) -> None:
key = version_uid.storage_object_to_path()
metadata_key = key + self._META_SUFFIX
if not overwrite:
try:
self._read_object(key)
except FileNotFoundError:
pass
else:
raise FileExistsError('Version {} already exists in storage.'.format(version_uid.v_string))
data_bytes = data.encode('utf-8')
size = len(data_bytes)
data_bytes, transforms_metadata = self._encapsulate(data_bytes)
metadata, metadata_json = self._build_metadata(
size=size, object_size=len(data_bytes), transforms_metadata=transforms_metadata)
try:
self._write_object(key, data_bytes)
self._write_object(metadata_key, metadata_json)
except:
try:
self._rm_object(key)
self._rm_object(metadata_key)
except FileNotFoundError:
pass
raise
if self._consistency_check_writes:
self._check_write(key=key, metadata_key=metadata_key, data_expected=data_bytes)
def test_version_uid_to_key(self):
for i in range(100):
version_uid = VersionUid('v{}'.format(
random.randint(1,
pow(2, 32) - 1)))
key = version_uid.storage_object_to_path()
version_uid_2 = VersionUid.storage_path_to_object(key)
self.assertEqual(version_uid, version_uid_2)
def rm_version(self, version_uid: VersionUid) -> None:
key = version_uid.storage_object_to_path()
metadata_key = key + self._META_SUFFIX
try:
self._rm_object(key)
finally:
try:
self._rm_object(metadata_key)
except FileNotFoundError:
pass
def read_version(self, version_uid: VersionUid) -> str:
key = version_uid.storage_object_to_path()
metadata_key = key + self._META_SUFFIX
data = self._read_object(key)
metadata_json = self._read_object(metadata_key)
metadata = self._decode_metadata(metadata_json=metadata_json, key=key, data_length=len(data))
if self._TRANSFORMS_KEY in metadata:
data = self._decapsulate(data, metadata[self._TRANSFORMS_KEY])
if len(data) != metadata[self._SIZE_KEY]:
raise ValueError('Length mismatch of original data for object {}. Expected: {}, got: {}.'.format(
key, metadata[self._SIZE_KEY], len(data)))
return data.decode('utf-8')
