kedro.io.AbstractDataSet¶
- class kedro.io.AbstractDataSet(*args, **kwds)[source]¶
AbstractDataSet
is the base class for all data set implementations. All data set implementations should extend this abstract class and implement the methods marked as abstract. If a specific dataset implementation cannot be used in conjunction with theParallelRunner
, such user-defined dataset should have the attribute _SINGLE_PROCESS = True. Example:from pathlib import Path, PurePosixPath import pandas as pd from kedro.io import AbstractDataSet class MyOwnDataSet(AbstractDataSet[pd.DataFrame, pd.DataFrame]): def __init__(self, filepath, param1, param2=True): self._filepath = PurePosixPath(filepath) self._param1 = param1 self._param2 = param2 def _load(self) -> pd.DataFrame: return pd.read_csv(self._filepath) def _save(self, df: pd.DataFrame) -> None: df.to_csv(str(self._filepath)) def _exists(self) -> bool: return Path(self._filepath.as_posix()).exists() def _describe(self): return dict(param1=self._param1, param2=self._param2)
Example catalog.yml specification:
my_dataset: type: <path-to-my-own-dataset>.MyOwnDataSet filepath: data/01_raw/my_data.csv param1: <param1-value> # param1 is a required argument # param2 will be True by default
Methods
exists
()Checks whether a data set's output already exists by calling the provided _exists() method.
from_config
(name, config[, load_version, ...])Create a data set instance using the configuration provided.
load
()Loads data by delegation to the provided load method.
release
()Release any cached data.
save
(data)Saves data by delegation to the provided save method.
- exists()[source]¶
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)[source]¶
Create a data set instance using the configuration provided.
- Parameters
name – Data set name.
config – Data set config dictionary.
load_version – 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 – 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.
- Returns
An instance of an
AbstractDataSet
subclass.- Raises
DataSetError – When the function fails to create the data set from its config.
- load()[source]¶
Loads data by delegation to the provided load method.
- Return type
TypeVar
(_DO
)- Returns
Data returned by the provided load method.
- Raises
DataSetError – When underlying load method raises error.
- release()[source]¶
Release any cached data.
- Raises
DataSetError – when underlying release method raises error.
- Return type
None
- save(data)[source]¶
Saves data by delegation to the provided save method.
- Parameters
data (
TypeVar
(_DI
)) – the value to be saved by provided save method.- Raises
DataSetError – when underlying save method raises error.
FileNotFoundError – when save method got file instead of dir, on Windows.
NotADirectoryError – when save method got file instead of dir, on Unix.
- Return type
None