kedro.extras.datasets.pandas.ParquetDataSet¶
-
class
kedro.extras.datasets.pandas.
ParquetDataSet
(filepath, load_args=None, save_args=None, version=None, credentials=None, fs_args=None)[source]¶ ParquetDataSet
loads/saves data from/to a Parquet file using an underlying filesystem (e.g.: local, S3, GCS). It uses pandas to handle the Parquet file.Example adding a catalog entry with YAML API:
boats: type: pandas.ParquetDataSet filepath: data/01_raw/boats.parquet load_args: engine: pyarrow use_nullable_dtypes: True save_args: file_scheme: hive has_nulls: False engine: pyarrow trucks: type: pandas.ParquetDataSet filepath: abfs://container/02_intermediate/trucks.parquet credentials: dev_abs load_args: columns: [name, gear, disp, wt] index: name save_args: compression: GZIP partition_on: [name]
Example using Python API:
from kedro.extras.datasets.pandas import ParquetDataSet import pandas as pd data = pd.DataFrame({'col1': [1, 2], 'col2': [4, 5], 'col3': [5, 6]}) # data_set = ParquetDataSet(filepath="gcs://bucket/test.parquet") data_set = ParquetDataSet(filepath="test.parquet") data_set.save(data) reloaded = data_set.load() assert data.equals(reloaded)
Attributes
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.
Compute the version the dataset should be loaded with.
Compute the version the dataset should be saved with.
save
(data)Saves data by delegation to the provided save method.
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DEFAULT_LOAD_ARGS
: Dict[str, Any] = {}¶
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DEFAULT_SAVE_ARGS
: Dict[str, Any] = {}¶
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__init__
(filepath, load_args=None, save_args=None, version=None, credentials=None, fs_args=None)[source]¶ Creates a new instance of
ParquetDataSet
pointing to a concrete Parquet file on a specific filesystem.- Parameters
filepath (
str
) – Filepath in POSIX format to a Parquet 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 byfsspec
. It can also be a path to a directory. If the directory is provided then it can be used for reading partitioned parquet files. Note: http(s) doesn’t support versioning.load_args (
Optional
[Dict
[str
,Any
]]) – Additional options for loading Parquet file(s). Here you can find all available arguments when reading single file: https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.read_parquet.html Here you can find all available arguments when reading partitioned datasets: https://arrow.apache.org/docs/python/generated/pyarrow.parquet.ParquetDataset.html#pyarrow.parquet.ParquetDataset.read All defaults are preserved.save_args (
Optional
[Dict
[str
,Any
]]) – Additional saving options for pyarrow.parquet.write_table and pyarrow.Table.from_pandas. Here you can find all available arguments for write_table(): https://arrow.apache.org/docs/python/generated/pyarrow.parquet.write_table.html?highlight=write_table#pyarrow.parquet.write_table The arguments for from_pandas() should be passed through a nested key: from_pandas. E.g.: save_args = {“from_pandas”: {“preserve_index”: False}} Here you can find all available arguments for from_pandas(): https://arrow.apache.org/docs/python/generated/pyarrow.Table.html#pyarrow.Table.from_pandasversion (
Optional
[Version
]) – If specified, should be an instance ofkedro.io.core.Version
. If itsload
attribute is None, the latest version will be loaded. If itssave
attribute is None, save version will be autogenerated.credentials (
Optional
[Dict
[str
,Any
]]) – Credentials required to get access to the underlying filesystem. E.g. forGCSFileSystem
it should look like {“token”: None}.fs_args (
Optional
[Dict
[str
,Any
]]) – Extra arguments to pass into underlying filesystem class constructor (e.g. {“project”: “my-project”} forGCSFileSystem
), as well as to pass to the filesystem’s open method through nested keys open_args_load and open_args_save. Here you can find all available arguments for open: https://filesystem-spec.readthedocs.io/en/latest/api.html#fsspec.spec.AbstractFileSystem.open All defaults are preserved.
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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.
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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 forload
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 forsave
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.
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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.
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release
()¶ Release any cached data.
- Raises
DataSetError – when underlying release method raises error.
- Return type
None
-
resolve_load_version
()¶ Compute the version the dataset should be loaded with.
- Return type
Optional
[str
]
-
resolve_save_version
()¶ Compute the version the dataset should be saved with.
- Return type
Optional
[str
]
-
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.
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
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