"""
Classes and functions to treat column data types according to
Deirokay data types.
"""
import datetime
from typing import Any, Iterable, List
import dask.dataframe # lazy module
import pandas # lazy module
from deirokay._typing import DeirokaySerializedSeries
from deirokay.enums import Backend, DTypes
from ..multibackend import serialize, treat
from .datetime64_treater import DateTime64Treater
[docs]class DateTreater(DateTime64Treater):
"""Treater for date-only variables"
Parameters
----------
format : str, optional
Format to parse dates from, by default '%Y-%m-%d'
"""
supported_backends = [Backend.PANDAS, Backend.DASK]
supported_dtype = DTypes.DATE
supported_primitives: List[Any] = [datetime.date]
def __init__(self, format: str = '%Y-%m-%d', **kwargs):
super().__init__(format, **kwargs)
@treat(Backend.PANDAS)
def _treat_pandas(self, series: Iterable) -> 'pandas.Series':
return super()._treat_pandas(series).dt.date
@treat(Backend.DASK)
def _treat_dask(
self, series: Iterable
) -> 'dask.dataframe.Series':
return super()._treat_dask(series).dt.date
@staticmethod
def _serialize_common(series):
def _convert(item):
if item is None or item is pandas.NaT:
return None
return str(item)
return {
'values': [_convert(item) for item in series],
'parser': {
'dtype': DateTreater.supported_dtype.value
}
}
@serialize(Backend.PANDAS)
@staticmethod
def _serialize_pandas(
series: 'pandas.Series'
) -> DeirokaySerializedSeries:
return DateTreater._serialize_common(series)
@serialize(Backend.DASK)
@staticmethod
def _serialize_dask(
series: 'dask.dataframe.Series'
) -> DeirokaySerializedSeries:
return DateTreater._serialize_common(series)