def load_dataset(self, dataset_key, force_update=False):
"""
Load a dataset from the local filesystem, downloading it from
data.world first, if necessary.
This function returns an object of type `LocalDataset`. The object
allows access to metedata via it's `describe()` method and to all the
data via three properties `raw_data`, `tables` and `dataframes`, all
of which are mappings (dict-like structures).
Parameters
----------
dataset_key : str
Dataset identifier, in the form of owner/id or of a url
force_update : bool
Flag, indicating if a new copy of the dataset should be downloaded
replacing any previously downloaded copy
Returns
-------
LocalDataset
The object representing the dataset
Raises
------
RestApiError
If a server error occurs
"""
owner_id, dataset_id = parse_dataset_key(dataset_key)
cache_dir = path.join(self._config.cache_dir, owner_id, dataset_id,
'latest')
backup_dir = None
if path.isdir(cache_dir) and force_update:
backup_dir = path.join(self._config.cache_dir, owner_id,
dataset_id, 'backup')
if path.isdir(backup_dir):
shutil.rmtree(backup_dir)
shutil.move(cache_dir, backup_dir)
descriptor_file = path.join(cache_dir, 'datapackage.json')
if not path.isfile(descriptor_file):
try:
descriptor_file = self.api_client.download_datapackage(
dataset_key, cache_dir)
except RestApiError as e:
if backup_dir is not None:
shutil.move(backup_dir, cache_dir)
warn('Unable to download datapackage ({}). '
'Loading previously saved version.'.format(e.reason))
else:
raise
if backup_dir is not None:
shutil.rmtree(backup_dir, ignore_errors=True)
return LocalDataset(descriptor_file)
def simpsons_broken_dataset(self, simpsons_broken_descriptor_path):
return LocalDataset(simpsons_broken_descriptor_path)
def load_dataset(self, dataset_key, force_update=False, auto_update=False):
"""Load a dataset from the local filesystem, downloading it from
data.world first, if necessary.
This function returns an object of type `LocalDataset`. The object
allows access to metedata via it's `describe()` method and to all the
data via three properties `raw_data`, `tables` and `dataframes`, all
of which are mappings (dict-like structures).
:param dataset_key: Dataset identifier, in the form of owner/id or of
a url
:type dataset_key: str
:param force_update: Flag, indicating if a new copy of the dataset
should be downloaded replacing any previously downloaded copy
(Default value = False)
:type force_update: bool
:param auto_update: Flag, indicating that dataset be updated to the
latest version
:type auto_update: bool
:returns: The object representing the dataset
:rtype: LocalDataset
:raises RestApiError: If a server error occurs
"""
owner_id, dataset_id = parse_dataset_key(dataset_key)
cache_dir = path.join(self._config.cache_dir, owner_id, dataset_id,
'latest')
backup_dir = None
if path.isdir(cache_dir) and force_update:
backup_dir = path.join(self._config.cache_dir, owner_id,
dataset_id, 'backup')
move_cache_dir_to_backup_dir(backup_dir, cache_dir)
descriptor_file = path.join(cache_dir, 'datapackage.json')
if not path.isfile(descriptor_file):
try:
descriptor_file = self.api_client.download_datapackage(
dataset_key, cache_dir)
except RestApiError as e:
if backup_dir is not None:
shutil.move(backup_dir, cache_dir)
warn('Unable to download datapackage ({}). '
'Loading previously saved version.'.format(e.reason))
else:
raise
else:
try:
dataset_info = self.api_client.get_dataset(dataset_key)
except RestApiError:
return LocalDataset(descriptor_file)
last_modified = datetime.strptime(dataset_info['updated'],
'%Y-%m-%dT%H:%M:%S.%fZ')
if (last_modified > datetime.utcfromtimestamp(
path.getmtime(str(descriptor_file)))):
if auto_update:
try:
backup_dir = path.join(self._config.cache_dir,
owner_id, dataset_id,
'backup')
move_cache_dir_to_backup_dir(backup_dir,
cache_dir)
descriptor_file = self.api_client. \
download_datapackage(dataset_key, cache_dir)
except RestApiError as e:
if backup_dir is not None:
shutil.move(backup_dir, cache_dir)
warn('Unable to auto update datapackage ({}). '
'Loading previously saved version.'
.format(e.reason))
else:
raise
else:
filterwarnings('always',
message='You are using an outdated copy')
warn('You are using an outdated copy of {}. '
'If you wish to use the latest version, call this '
'function with the argument '
'auto_update=True or '
'force_update=True'.format(dataset_key))
if backup_dir is not None:
shutil.rmtree(backup_dir, ignore_errors=True)
return LocalDataset(descriptor_file)