def _has_hash(path: str, expected_hash: str) -> bool:
"""Check if the provided path has the expected hash.
Parameters
----------
path: str
expected_hash: str
Returns
-------
bool
True if the file hash and the expected one are equal
"""
if not os.path.exists(path):
return False
return file_hash(path) == expected_hash
def fetch(self, fname, processor=None, downloader=None):
self._assert_file_in_registry(fname)
# Create the local data directory if it doesn't already exist
if not self.abspath.exists():
os.makedirs(str(self.abspath))
full_path = self.abspath / fname
in_storage = full_path.exists()
if not in_storage:
action = 'download'
elif in_storage and file_hash(str(full_path)) != self.registry[fname]:
action = 'update'
else:
action = 'fetch'
if action in ('download', 'update'):
action_word = dict(download='Downloading', update='Updating')
warn("{} data file '{}' from remote data store '{}' to '{}'.".
format(action_word[action], fname, self.get_url(fname),
str(self.path)))
if downloader is None:
downloader = Downloader()
# Stream the file to a temporary so that we can safely check its hash before
# overwriting the original
tmp = tempfile.NamedTemporaryFile(delete=False,
dir=str(self.abspath))
# Close the temp file so that the downloader can decide how to opened it
tmp.close()
try:
downloader(self.get_url(fname), tmp.name, self)
self._check_download_hash(fname, tmp.name)
# Ensure the parent directory exists in case the file is in a
# subdirectory. Otherwise, move will cause an error.
if not os.path.exists(str(full_path.parent)):
os.makedirs(str(full_path.parent))
shutil.move(tmp.name, str(full_path))
finally:
if os.path.exists(tmp.name):
os.remove(tmp.name)
if processor is not None:
return processor(str(full_path), action, self)
return str(full_path)
def _has_hash(path, expected_hash):
"""Check if the provided path has the expected hash."""
if not osp.exists(path):
return False
return file_hash(path) == expected_hash