kedro.extras.datasets.pandas.HDFDataSet

class kedro.extras.datasets.pandas.HDFDataSet(filepath, key, load_args=None, save_args=None, version=None, credentials=None, fs_args=None, layer=None)[source]

Bases: kedro.io.core.AbstractVersionedDataSet

HDFDataSet loads/saves data from/to a hdf file using an underlying filesystem (e.g. local, S3, GCS). It uses pandas.HDFStore to handle the hdf file.

Example:

from kedro.extras.datasets.pandas import HDFDataSet
import pandas as pd

data = pd.DataFrame({'col1': [1, 2], 'col2': [4, 5],
                     'col3': [5, 6]})

# data_set = HDFDataSet(filepath="gcs://bucket/test.hdf", key='data')
data_set = HDFDataSet(filepath="test.h5", key='data')
data_set.save(data)
reloaded = data_set.load()
assert data.equals(reloaded)

Attributes

HDFDataSet.DEFAULT_LOAD_ARGS
HDFDataSet.DEFAULT_SAVE_ARGS

Methods

HDFDataSet.__init__(filepath, key[, …]) Creates a new instance of HDFDataSet pointing to a concrete hdf file on a specific filesystem.
HDFDataSet.exists() Checks whether a data set’s output already exists by calling the provided _exists() method.
HDFDataSet.from_config(name, config[, …]) Create a data set instance using the configuration provided.
HDFDataSet.get_last_load_version() Versioned datasets should override this property to return last loaded version
HDFDataSet.get_last_save_version() Versioned datasets should override this property to return last saved version.
HDFDataSet.invalidate_cache() Invalidate underlying filesystem caches.
HDFDataSet.load() Loads data by delegation to the provided load method.
HDFDataSet.release() Release any cached data.
HDFDataSet.save(data) Saves data by delegation to the provided save method.
DEFAULT_LOAD_ARGS = {}
DEFAULT_SAVE_ARGS = {}
__init__(filepath, key, load_args=None, save_args=None, version=None, credentials=None, fs_args=None, layer=None)[source]

Creates a new instance of HDFDataSet pointing to a concrete hdf file on a specific filesystem.

Parameters:
  • filepath (str) – Filepath to a hdf file prefixed with a protocol like s3://. If prefix is not provided, file protocol (local filesystem) will be used. The prefix should be any protocol supported by fsspec. Note: http(s) doesn’t support versioning.
  • key (str) – Identifier to the group in the HDF store.
  • load_args (Optional[Dict[str, Any]]) – PyTables options for loading hdf files. You can find all available arguments at: https://www.pytables.org/usersguide/libref/top_level.html#tables.open_file All defaults are preserved.
  • save_args (Optional[Dict[str, Any]]) – PyTables options for saving hdf files. You can find all available arguments at: https://www.pytables.org/usersguide/libref/top_level.html#tables.open_file All defaults are preserved.
  • version (Optional[Version]) – If specified, should be an instance of kedro.io.core.Version. If its load attribute is None, the latest version will be loaded. If its save attribute is None, save version will be autogenerated.
  • credentials (Optional[Dict[str, Any]]) – Credentials required to get access to the underlying filesystem. E.g. for GCSFileSystem it should look like {“token”: None}.
  • fs_args (Optional[Dict[str, Any]]) – Extra arguments to pass into underlying filesystem class. E.g. for GCSFileSystem class: {“project”: “my-project”, …}
  • layer (Optional[str]) – The data layer according to the data engineering convention: https://kedro.readthedocs.io/en/stable/06_resources/01_faq.html#what-is-data-engineering-convention
Return type:

None

exists()

Checks whether a data set’s output already exists by calling the provided _exists() method.

Return type:bool
Returns:Flag indicating whether the output already exists.
Raises:DataSetError – when underlying exists method raises error.
classmethod from_config(name, config, load_version=None, save_version=None)

Create a data set instance using the configuration provided.

Parameters:
  • name (str) – Data set name.
  • config (Dict[str, Any]) – Data set config dictionary.
  • load_version (Optional[str]) – Version string to be used for load operation if the data set is versioned. Has no effect on the data set if versioning was not enabled.
  • save_version (Optional[str]) – Version string to be used for save operation if the data set is versioned. Has no effect on the data set if versioning was not enabled.
Return type:

AbstractDataSet

Returns:

An instance of an AbstractDataSet subclass.

Raises:

DataSetError – When the function fails to create the data set from its config.

get_last_load_version()

Versioned datasets should override this property to return last loaded version

Return type:Optional[str]
get_last_save_version()

Versioned datasets should override this property to return last saved version.

Return type:Optional[str]
invalidate_cache()[source]

Invalidate underlying filesystem caches.

Return type:None
load()

Loads data by delegation to the provided load method.

Return type:Any
Returns:Data returned by the provided load method.
Raises:DataSetError – When underlying load method raises error.
release()

Release any cached data.

Raises:DataSetError – when underlying exists method raises error.
Return type:None
save(data)

Saves data by delegation to the provided save method.

Parameters:data (Any) – the value to be saved by provided save method.
Raises:DataSetError – when underlying save method raises error.
Return type:None