1173 lines
36 KiB
Python
1173 lines
36 KiB
Python
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from abc import ABC, abstractmethod
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from collections import abc
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import functools
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from io import StringIO
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from itertools import islice
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from typing import Any, Callable, Mapping, Optional, Tuple, Type, Union
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import numpy as np
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import pandas._libs.json as json
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from pandas._libs.tslibs import iNaT
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from pandas._typing import (
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CompressionOptions,
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IndexLabel,
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JSONSerializable,
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StorageOptions,
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)
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from pandas.errors import AbstractMethodError
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from pandas.util._decorators import deprecate_kwarg, deprecate_nonkeyword_arguments, doc
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from pandas.core.dtypes.common import ensure_str, is_period_dtype
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from pandas import DataFrame, MultiIndex, Series, isna, notna, to_datetime
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from pandas.core import generic
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from pandas.core.construction import create_series_with_explicit_dtype
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from pandas.core.generic import NDFrame
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from pandas.core.reshape.concat import concat
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from pandas.io.common import (
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IOHandles,
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file_exists,
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get_handle,
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is_fsspec_url,
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is_url,
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stringify_path,
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)
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from pandas.io.json._normalize import convert_to_line_delimits
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from pandas.io.json._table_schema import build_table_schema, parse_table_schema
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from pandas.io.parsers import validate_integer
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loads = json.loads
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dumps = json.dumps
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TABLE_SCHEMA_VERSION = "0.20.0"
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# interface to/from
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def to_json(
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path_or_buf,
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obj: NDFrame,
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orient: Optional[str] = None,
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date_format: str = "epoch",
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double_precision: int = 10,
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force_ascii: bool = True,
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date_unit: str = "ms",
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default_handler: Optional[Callable[[Any], JSONSerializable]] = None,
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lines: bool = False,
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compression: CompressionOptions = "infer",
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index: bool = True,
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indent: int = 0,
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storage_options: StorageOptions = None,
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):
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if not index and orient not in ["split", "table"]:
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raise ValueError(
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"'index=False' is only valid when 'orient' is 'split' or 'table'"
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)
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if lines and orient != "records":
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raise ValueError("'lines' keyword only valid when 'orient' is records")
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if orient == "table" and isinstance(obj, Series):
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obj = obj.to_frame(name=obj.name or "values")
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writer: Type["Writer"]
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if orient == "table" and isinstance(obj, DataFrame):
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writer = JSONTableWriter
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elif isinstance(obj, Series):
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writer = SeriesWriter
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elif isinstance(obj, DataFrame):
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writer = FrameWriter
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else:
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raise NotImplementedError("'obj' should be a Series or a DataFrame")
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s = writer(
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obj,
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orient=orient,
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date_format=date_format,
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double_precision=double_precision,
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ensure_ascii=force_ascii,
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date_unit=date_unit,
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default_handler=default_handler,
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index=index,
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indent=indent,
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).write()
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if lines:
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s = convert_to_line_delimits(s)
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if path_or_buf is not None:
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# apply compression and byte/text conversion
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with get_handle(
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path_or_buf, "w", compression=compression, storage_options=storage_options
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) as handles:
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handles.handle.write(s)
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else:
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return s
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class Writer(ABC):
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_default_orient: str
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def __init__(
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self,
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obj,
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orient: Optional[str],
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date_format: str,
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double_precision: int,
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ensure_ascii: bool,
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date_unit: str,
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index: bool,
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default_handler: Optional[Callable[[Any], JSONSerializable]] = None,
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indent: int = 0,
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):
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self.obj = obj
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if orient is None:
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orient = self._default_orient
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self.orient = orient
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self.date_format = date_format
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self.double_precision = double_precision
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self.ensure_ascii = ensure_ascii
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self.date_unit = date_unit
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self.default_handler = default_handler
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self.index = index
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self.indent = indent
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self.is_copy = None
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self._format_axes()
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def _format_axes(self):
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raise AbstractMethodError(self)
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def write(self):
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iso_dates = self.date_format == "iso"
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return dumps(
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self.obj_to_write,
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orient=self.orient,
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double_precision=self.double_precision,
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ensure_ascii=self.ensure_ascii,
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date_unit=self.date_unit,
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iso_dates=iso_dates,
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default_handler=self.default_handler,
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indent=self.indent,
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)
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@property
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@abstractmethod
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def obj_to_write(self) -> Union[NDFrame, Mapping[IndexLabel, Any]]:
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"""Object to write in JSON format."""
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pass
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class SeriesWriter(Writer):
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_default_orient = "index"
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@property
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def obj_to_write(self) -> Union[NDFrame, Mapping[IndexLabel, Any]]:
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if not self.index and self.orient == "split":
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return {"name": self.obj.name, "data": self.obj.values}
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else:
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return self.obj
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def _format_axes(self):
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if not self.obj.index.is_unique and self.orient == "index":
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raise ValueError(f"Series index must be unique for orient='{self.orient}'")
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class FrameWriter(Writer):
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_default_orient = "columns"
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@property
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def obj_to_write(self) -> Union[NDFrame, Mapping[IndexLabel, Any]]:
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if not self.index and self.orient == "split":
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obj_to_write = self.obj.to_dict(orient="split")
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del obj_to_write["index"]
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else:
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obj_to_write = self.obj
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return obj_to_write
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def _format_axes(self):
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"""
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Try to format axes if they are datelike.
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"""
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if not self.obj.index.is_unique and self.orient in ("index", "columns"):
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raise ValueError(
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f"DataFrame index must be unique for orient='{self.orient}'."
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)
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if not self.obj.columns.is_unique and self.orient in (
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"index",
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"columns",
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"records",
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):
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raise ValueError(
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f"DataFrame columns must be unique for orient='{self.orient}'."
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)
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class JSONTableWriter(FrameWriter):
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_default_orient = "records"
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def __init__(
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self,
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obj,
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orient: Optional[str],
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date_format: str,
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double_precision: int,
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ensure_ascii: bool,
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date_unit: str,
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index: bool,
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default_handler: Optional[Callable[[Any], JSONSerializable]] = None,
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indent: int = 0,
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):
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"""
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Adds a `schema` attribute with the Table Schema, resets
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the index (can't do in caller, because the schema inference needs
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to know what the index is, forces orient to records, and forces
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date_format to 'iso'.
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"""
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super().__init__(
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obj,
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orient,
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date_format,
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double_precision,
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ensure_ascii,
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date_unit,
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index,
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default_handler=default_handler,
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indent=indent,
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)
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if date_format != "iso":
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msg = (
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"Trying to write with `orient='table'` and "
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f"`date_format='{date_format}'`. Table Schema requires dates "
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"to be formatted with `date_format='iso'`"
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)
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raise ValueError(msg)
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self.schema = build_table_schema(obj, index=self.index)
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# NotImplemented on a column MultiIndex
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if obj.ndim == 2 and isinstance(obj.columns, MultiIndex):
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raise NotImplementedError(
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"orient='table' is not supported for MultiIndex columns"
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)
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# TODO: Do this timedelta properly in objToJSON.c See GH #15137
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if (
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(obj.ndim == 1)
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and (obj.name in set(obj.index.names))
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or len(obj.columns.intersection(obj.index.names))
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):
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msg = "Overlapping names between the index and columns"
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raise ValueError(msg)
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obj = obj.copy()
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timedeltas = obj.select_dtypes(include=["timedelta"]).columns
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if len(timedeltas):
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obj[timedeltas] = obj[timedeltas].applymap(lambda x: x.isoformat())
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# Convert PeriodIndex to datetimes before serializing
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if is_period_dtype(obj.index.dtype):
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obj.index = obj.index.to_timestamp()
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# exclude index from obj if index=False
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if not self.index:
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self.obj = obj.reset_index(drop=True)
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else:
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self.obj = obj.reset_index(drop=False)
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self.date_format = "iso"
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self.orient = "records"
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self.index = index
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@property
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def obj_to_write(self) -> Union[NDFrame, Mapping[IndexLabel, Any]]:
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return {"schema": self.schema, "data": self.obj}
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@doc(storage_options=generic._shared_docs["storage_options"])
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@deprecate_kwarg(old_arg_name="numpy", new_arg_name=None)
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@deprecate_nonkeyword_arguments(
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version="2.0", allowed_args=["path_or_buf"], stacklevel=3
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)
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def read_json(
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path_or_buf=None,
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orient=None,
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typ="frame",
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dtype=None,
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convert_axes=None,
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convert_dates=True,
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keep_default_dates: bool = True,
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numpy: bool = False,
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precise_float: bool = False,
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date_unit=None,
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encoding=None,
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lines: bool = False,
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chunksize: Optional[int] = None,
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compression: CompressionOptions = "infer",
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nrows: Optional[int] = None,
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storage_options: StorageOptions = None,
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):
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"""
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Convert a JSON string to pandas object.
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Parameters
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----------
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path_or_buf : a valid JSON str, path object or file-like object
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Any valid string path is acceptable. The string could be a URL. Valid
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URL schemes include http, ftp, s3, and file. For file URLs, a host is
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expected. A local file could be:
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``file://localhost/path/to/table.json``.
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If you want to pass in a path object, pandas accepts any
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``os.PathLike``.
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By file-like object, we refer to objects with a ``read()`` method,
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such as a file handle (e.g. via builtin ``open`` function)
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or ``StringIO``.
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orient : str
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Indication of expected JSON string format.
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Compatible JSON strings can be produced by ``to_json()`` with a
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corresponding orient value.
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The set of possible orients is:
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- ``'split'`` : dict like
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``{{index -> [index], columns -> [columns], data -> [values]}}``
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- ``'records'`` : list like
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``[{{column -> value}}, ... , {{column -> value}}]``
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- ``'index'`` : dict like ``{{index -> {{column -> value}}}}``
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- ``'columns'`` : dict like ``{{column -> {{index -> value}}}}``
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- ``'values'`` : just the values array
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The allowed and default values depend on the value
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of the `typ` parameter.
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|
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* when ``typ == 'series'``,
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|
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- allowed orients are ``{{'split','records','index'}}``
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- default is ``'index'``
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- The Series index must be unique for orient ``'index'``.
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|
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|
* when ``typ == 'frame'``,
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|
|
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- allowed orients are ``{{'split','records','index',
|
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'columns','values', 'table'}}``
|
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- default is ``'columns'``
|
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- The DataFrame index must be unique for orients ``'index'`` and
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``'columns'``.
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|
- The DataFrame columns must be unique for orients ``'index'``,
|
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|
``'columns'``, and ``'records'``.
|
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|
|
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|
typ : {{'frame', 'series'}}, default 'frame'
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|
The type of object to recover.
|
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|
|
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|
dtype : bool or dict, default None
|
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|
If True, infer dtypes; if a dict of column to dtype, then use those;
|
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|
if False, then don't infer dtypes at all, applies only to the data.
|
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|
|
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|
For all ``orient`` values except ``'table'``, default is True.
|
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|
|
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|
.. versionchanged:: 0.25.0
|
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|
|
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|
Not applicable for ``orient='table'``.
|
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|
|
||
|
convert_axes : bool, default None
|
||
|
Try to convert the axes to the proper dtypes.
|
||
|
|
||
|
For all ``orient`` values except ``'table'``, default is True.
|
||
|
|
||
|
.. versionchanged:: 0.25.0
|
||
|
|
||
|
Not applicable for ``orient='table'``.
|
||
|
|
||
|
convert_dates : bool or list of str, default True
|
||
|
If True then default datelike columns may be converted (depending on
|
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|
keep_default_dates).
|
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|
If False, no dates will be converted.
|
||
|
If a list of column names, then those columns will be converted and
|
||
|
default datelike columns may also be converted (depending on
|
||
|
keep_default_dates).
|
||
|
|
||
|
keep_default_dates : bool, default True
|
||
|
If parsing dates (convert_dates is not False), then try to parse the
|
||
|
default datelike columns.
|
||
|
A column label is datelike if
|
||
|
|
||
|
* it ends with ``'_at'``,
|
||
|
|
||
|
* it ends with ``'_time'``,
|
||
|
|
||
|
* it begins with ``'timestamp'``,
|
||
|
|
||
|
* it is ``'modified'``, or
|
||
|
|
||
|
* it is ``'date'``.
|
||
|
|
||
|
numpy : bool, default False
|
||
|
Direct decoding to numpy arrays. Supports numeric data only, but
|
||
|
non-numeric column and index labels are supported. Note also that the
|
||
|
JSON ordering MUST be the same for each term if numpy=True.
|
||
|
|
||
|
.. deprecated:: 1.0.0
|
||
|
|
||
|
precise_float : bool, default False
|
||
|
Set to enable usage of higher precision (strtod) function when
|
||
|
decoding string to double values. Default (False) is to use fast but
|
||
|
less precise builtin functionality.
|
||
|
|
||
|
date_unit : str, default None
|
||
|
The timestamp unit to detect if converting dates. The default behaviour
|
||
|
is to try and detect the correct precision, but if this is not desired
|
||
|
then pass one of 's', 'ms', 'us' or 'ns' to force parsing only seconds,
|
||
|
milliseconds, microseconds or nanoseconds respectively.
|
||
|
|
||
|
encoding : str, default is 'utf-8'
|
||
|
The encoding to use to decode py3 bytes.
|
||
|
|
||
|
lines : bool, default False
|
||
|
Read the file as a json object per line.
|
||
|
|
||
|
chunksize : int, optional
|
||
|
Return JsonReader object for iteration.
|
||
|
See the `line-delimited json docs
|
||
|
<https://pandas.pydata.org/pandas-docs/stable/user_guide/io.html#line-delimited-json>`_
|
||
|
for more information on ``chunksize``.
|
||
|
This can only be passed if `lines=True`.
|
||
|
If this is None, the file will be read into memory all at once.
|
||
|
|
||
|
.. versionchanged:: 1.2
|
||
|
|
||
|
``JsonReader`` is a context manager.
|
||
|
|
||
|
compression : {{'infer', 'gzip', 'bz2', 'zip', 'xz', None}}, default 'infer'
|
||
|
For on-the-fly decompression of on-disk data. If 'infer', then use
|
||
|
gzip, bz2, zip or xz if path_or_buf is a string ending in
|
||
|
'.gz', '.bz2', '.zip', or 'xz', respectively, and no decompression
|
||
|
otherwise. If using 'zip', the ZIP file must contain only one data
|
||
|
file to be read in. Set to None for no decompression.
|
||
|
|
||
|
nrows : int, optional
|
||
|
The number of lines from the line-delimited jsonfile that has to be read.
|
||
|
This can only be passed if `lines=True`.
|
||
|
If this is None, all the rows will be returned.
|
||
|
|
||
|
.. versionadded:: 1.1
|
||
|
|
||
|
{storage_options}
|
||
|
|
||
|
.. versionadded:: 1.2.0
|
||
|
|
||
|
Returns
|
||
|
-------
|
||
|
Series or DataFrame
|
||
|
The type returned depends on the value of `typ`.
|
||
|
|
||
|
See Also
|
||
|
--------
|
||
|
DataFrame.to_json : Convert a DataFrame to a JSON string.
|
||
|
Series.to_json : Convert a Series to a JSON string.
|
||
|
|
||
|
Notes
|
||
|
-----
|
||
|
Specific to ``orient='table'``, if a :class:`DataFrame` with a literal
|
||
|
:class:`Index` name of `index` gets written with :func:`to_json`, the
|
||
|
subsequent read operation will incorrectly set the :class:`Index` name to
|
||
|
``None``. This is because `index` is also used by :func:`DataFrame.to_json`
|
||
|
to denote a missing :class:`Index` name, and the subsequent
|
||
|
:func:`read_json` operation cannot distinguish between the two. The same
|
||
|
limitation is encountered with a :class:`MultiIndex` and any names
|
||
|
beginning with ``'level_'``.
|
||
|
|
||
|
Examples
|
||
|
--------
|
||
|
>>> df = pd.DataFrame([['a', 'b'], ['c', 'd']],
|
||
|
... index=['row 1', 'row 2'],
|
||
|
... columns=['col 1', 'col 2'])
|
||
|
|
||
|
Encoding/decoding a Dataframe using ``'split'`` formatted JSON:
|
||
|
|
||
|
>>> df.to_json(orient='split')
|
||
|
'{{"columns":["col 1","col 2"],
|
||
|
"index":["row 1","row 2"],
|
||
|
"data":[["a","b"],["c","d"]]}}'
|
||
|
>>> pd.read_json(_, orient='split')
|
||
|
col 1 col 2
|
||
|
row 1 a b
|
||
|
row 2 c d
|
||
|
|
||
|
Encoding/decoding a Dataframe using ``'index'`` formatted JSON:
|
||
|
|
||
|
>>> df.to_json(orient='index')
|
||
|
'{{"row 1":{{"col 1":"a","col 2":"b"}},"row 2":{{"col 1":"c","col 2":"d"}}}}'
|
||
|
>>> pd.read_json(_, orient='index')
|
||
|
col 1 col 2
|
||
|
row 1 a b
|
||
|
row 2 c d
|
||
|
|
||
|
Encoding/decoding a Dataframe using ``'records'`` formatted JSON.
|
||
|
Note that index labels are not preserved with this encoding.
|
||
|
|
||
|
>>> df.to_json(orient='records')
|
||
|
'[{{"col 1":"a","col 2":"b"}},{{"col 1":"c","col 2":"d"}}]'
|
||
|
>>> pd.read_json(_, orient='records')
|
||
|
col 1 col 2
|
||
|
0 a b
|
||
|
1 c d
|
||
|
|
||
|
Encoding with Table Schema
|
||
|
|
||
|
>>> df.to_json(orient='table')
|
||
|
'{{"schema": {{"fields": [{{"name": "index", "type": "string"}},
|
||
|
{{"name": "col 1", "type": "string"}},
|
||
|
{{"name": "col 2", "type": "string"}}],
|
||
|
"primaryKey": "index",
|
||
|
"pandas_version": "0.20.0"}},
|
||
|
"data": [{{"index": "row 1", "col 1": "a", "col 2": "b"}},
|
||
|
{{"index": "row 2", "col 1": "c", "col 2": "d"}}]}}'
|
||
|
"""
|
||
|
if orient == "table" and dtype:
|
||
|
raise ValueError("cannot pass both dtype and orient='table'")
|
||
|
if orient == "table" and convert_axes:
|
||
|
raise ValueError("cannot pass both convert_axes and orient='table'")
|
||
|
|
||
|
if dtype is None and orient != "table":
|
||
|
dtype = True
|
||
|
if convert_axes is None and orient != "table":
|
||
|
convert_axes = True
|
||
|
|
||
|
json_reader = JsonReader(
|
||
|
path_or_buf,
|
||
|
orient=orient,
|
||
|
typ=typ,
|
||
|
dtype=dtype,
|
||
|
convert_axes=convert_axes,
|
||
|
convert_dates=convert_dates,
|
||
|
keep_default_dates=keep_default_dates,
|
||
|
numpy=numpy,
|
||
|
precise_float=precise_float,
|
||
|
date_unit=date_unit,
|
||
|
encoding=encoding,
|
||
|
lines=lines,
|
||
|
chunksize=chunksize,
|
||
|
compression=compression,
|
||
|
nrows=nrows,
|
||
|
storage_options=storage_options,
|
||
|
)
|
||
|
|
||
|
if chunksize:
|
||
|
return json_reader
|
||
|
|
||
|
with json_reader:
|
||
|
return json_reader.read()
|
||
|
|
||
|
|
||
|
class JsonReader(abc.Iterator):
|
||
|
"""
|
||
|
JsonReader provides an interface for reading in a JSON file.
|
||
|
|
||
|
If initialized with ``lines=True`` and ``chunksize``, can be iterated over
|
||
|
``chunksize`` lines at a time. Otherwise, calling ``read`` reads in the
|
||
|
whole document.
|
||
|
"""
|
||
|
|
||
|
def __init__(
|
||
|
self,
|
||
|
filepath_or_buffer,
|
||
|
orient,
|
||
|
typ,
|
||
|
dtype,
|
||
|
convert_axes,
|
||
|
convert_dates,
|
||
|
keep_default_dates: bool,
|
||
|
numpy: bool,
|
||
|
precise_float: bool,
|
||
|
date_unit,
|
||
|
encoding,
|
||
|
lines: bool,
|
||
|
chunksize: Optional[int],
|
||
|
compression: CompressionOptions,
|
||
|
nrows: Optional[int],
|
||
|
storage_options: StorageOptions = None,
|
||
|
):
|
||
|
|
||
|
self.orient = orient
|
||
|
self.typ = typ
|
||
|
self.dtype = dtype
|
||
|
self.convert_axes = convert_axes
|
||
|
self.convert_dates = convert_dates
|
||
|
self.keep_default_dates = keep_default_dates
|
||
|
self.numpy = numpy
|
||
|
self.precise_float = precise_float
|
||
|
self.date_unit = date_unit
|
||
|
self.encoding = encoding
|
||
|
self.compression = compression
|
||
|
self.storage_options = storage_options
|
||
|
self.lines = lines
|
||
|
self.chunksize = chunksize
|
||
|
self.nrows_seen = 0
|
||
|
self.nrows = nrows
|
||
|
self.handles: Optional[IOHandles] = None
|
||
|
|
||
|
if self.chunksize is not None:
|
||
|
self.chunksize = validate_integer("chunksize", self.chunksize, 1)
|
||
|
if not self.lines:
|
||
|
raise ValueError("chunksize can only be passed if lines=True")
|
||
|
if self.nrows is not None:
|
||
|
self.nrows = validate_integer("nrows", self.nrows, 0)
|
||
|
if not self.lines:
|
||
|
raise ValueError("nrows can only be passed if lines=True")
|
||
|
|
||
|
data = self._get_data_from_filepath(filepath_or_buffer)
|
||
|
self.data = self._preprocess_data(data)
|
||
|
|
||
|
def _preprocess_data(self, data):
|
||
|
"""
|
||
|
At this point, the data either has a `read` attribute (e.g. a file
|
||
|
object or a StringIO) or is a string that is a JSON document.
|
||
|
|
||
|
If self.chunksize, we prepare the data for the `__next__` method.
|
||
|
Otherwise, we read it into memory for the `read` method.
|
||
|
"""
|
||
|
if hasattr(data, "read") and not (self.chunksize or self.nrows):
|
||
|
data = data.read()
|
||
|
self.close()
|
||
|
if not hasattr(data, "read") and (self.chunksize or self.nrows):
|
||
|
data = StringIO(data)
|
||
|
|
||
|
return data
|
||
|
|
||
|
def _get_data_from_filepath(self, filepath_or_buffer):
|
||
|
"""
|
||
|
The function read_json accepts three input types:
|
||
|
1. filepath (string-like)
|
||
|
2. file-like object (e.g. open file object, StringIO)
|
||
|
3. JSON string
|
||
|
|
||
|
This method turns (1) into (2) to simplify the rest of the processing.
|
||
|
It returns input types (2) and (3) unchanged.
|
||
|
"""
|
||
|
# if it is a string but the file does not exist, it might be a JSON string
|
||
|
filepath_or_buffer = stringify_path(filepath_or_buffer)
|
||
|
if (
|
||
|
not isinstance(filepath_or_buffer, str)
|
||
|
or is_url(filepath_or_buffer)
|
||
|
or is_fsspec_url(filepath_or_buffer)
|
||
|
or file_exists(filepath_or_buffer)
|
||
|
):
|
||
|
self.handles = get_handle(
|
||
|
filepath_or_buffer,
|
||
|
"r",
|
||
|
encoding=self.encoding,
|
||
|
compression=self.compression,
|
||
|
storage_options=self.storage_options,
|
||
|
)
|
||
|
filepath_or_buffer = self.handles.handle
|
||
|
|
||
|
return filepath_or_buffer
|
||
|
|
||
|
def _combine_lines(self, lines) -> str:
|
||
|
"""
|
||
|
Combines a list of JSON objects into one JSON object.
|
||
|
"""
|
||
|
return (
|
||
|
f'[{",".join((line for line in (line.strip() for line in lines) if line))}]'
|
||
|
)
|
||
|
|
||
|
def read(self):
|
||
|
"""
|
||
|
Read the whole JSON input into a pandas object.
|
||
|
"""
|
||
|
if self.lines:
|
||
|
if self.chunksize:
|
||
|
obj = concat(self)
|
||
|
elif self.nrows:
|
||
|
lines = list(islice(self.data, self.nrows))
|
||
|
lines_json = self._combine_lines(lines)
|
||
|
obj = self._get_object_parser(lines_json)
|
||
|
else:
|
||
|
data = ensure_str(self.data)
|
||
|
data_lines = data.split("\n")
|
||
|
obj = self._get_object_parser(self._combine_lines(data_lines))
|
||
|
else:
|
||
|
obj = self._get_object_parser(self.data)
|
||
|
self.close()
|
||
|
return obj
|
||
|
|
||
|
def _get_object_parser(self, json):
|
||
|
"""
|
||
|
Parses a json document into a pandas object.
|
||
|
"""
|
||
|
typ = self.typ
|
||
|
dtype = self.dtype
|
||
|
kwargs = {
|
||
|
"orient": self.orient,
|
||
|
"dtype": self.dtype,
|
||
|
"convert_axes": self.convert_axes,
|
||
|
"convert_dates": self.convert_dates,
|
||
|
"keep_default_dates": self.keep_default_dates,
|
||
|
"numpy": self.numpy,
|
||
|
"precise_float": self.precise_float,
|
||
|
"date_unit": self.date_unit,
|
||
|
}
|
||
|
obj = None
|
||
|
if typ == "frame":
|
||
|
obj = FrameParser(json, **kwargs).parse()
|
||
|
|
||
|
if typ == "series" or obj is None:
|
||
|
if not isinstance(dtype, bool):
|
||
|
kwargs["dtype"] = dtype
|
||
|
obj = SeriesParser(json, **kwargs).parse()
|
||
|
|
||
|
return obj
|
||
|
|
||
|
def close(self):
|
||
|
"""
|
||
|
If we opened a stream earlier, in _get_data_from_filepath, we should
|
||
|
close it.
|
||
|
|
||
|
If an open stream or file was passed, we leave it open.
|
||
|
"""
|
||
|
if self.handles is not None:
|
||
|
self.handles.close()
|
||
|
|
||
|
def __next__(self):
|
||
|
if self.nrows:
|
||
|
if self.nrows_seen >= self.nrows:
|
||
|
self.close()
|
||
|
raise StopIteration
|
||
|
|
||
|
lines = list(islice(self.data, self.chunksize))
|
||
|
if lines:
|
||
|
lines_json = self._combine_lines(lines)
|
||
|
obj = self._get_object_parser(lines_json)
|
||
|
|
||
|
# Make sure that the returned objects have the right index.
|
||
|
obj.index = range(self.nrows_seen, self.nrows_seen + len(obj))
|
||
|
self.nrows_seen += len(obj)
|
||
|
|
||
|
return obj
|
||
|
|
||
|
self.close()
|
||
|
raise StopIteration
|
||
|
|
||
|
def __enter__(self):
|
||
|
return self
|
||
|
|
||
|
def __exit__(self, exc_type, exc_value, traceback):
|
||
|
self.close()
|
||
|
|
||
|
|
||
|
class Parser:
|
||
|
_split_keys: Tuple[str, ...]
|
||
|
_default_orient: str
|
||
|
|
||
|
_STAMP_UNITS = ("s", "ms", "us", "ns")
|
||
|
_MIN_STAMPS = {
|
||
|
"s": 31536000,
|
||
|
"ms": 31536000000,
|
||
|
"us": 31536000000000,
|
||
|
"ns": 31536000000000000,
|
||
|
}
|
||
|
|
||
|
def __init__(
|
||
|
self,
|
||
|
json,
|
||
|
orient,
|
||
|
dtype=None,
|
||
|
convert_axes=True,
|
||
|
convert_dates=True,
|
||
|
keep_default_dates=False,
|
||
|
numpy=False,
|
||
|
precise_float=False,
|
||
|
date_unit=None,
|
||
|
):
|
||
|
self.json = json
|
||
|
|
||
|
if orient is None:
|
||
|
orient = self._default_orient
|
||
|
|
||
|
self.orient = orient
|
||
|
|
||
|
self.dtype = dtype
|
||
|
|
||
|
if orient == "split":
|
||
|
numpy = False
|
||
|
|
||
|
if date_unit is not None:
|
||
|
date_unit = date_unit.lower()
|
||
|
if date_unit not in self._STAMP_UNITS:
|
||
|
raise ValueError(f"date_unit must be one of {self._STAMP_UNITS}")
|
||
|
self.min_stamp = self._MIN_STAMPS[date_unit]
|
||
|
else:
|
||
|
self.min_stamp = self._MIN_STAMPS["s"]
|
||
|
|
||
|
self.numpy = numpy
|
||
|
self.precise_float = precise_float
|
||
|
self.convert_axes = convert_axes
|
||
|
self.convert_dates = convert_dates
|
||
|
self.date_unit = date_unit
|
||
|
self.keep_default_dates = keep_default_dates
|
||
|
self.obj = None
|
||
|
|
||
|
def check_keys_split(self, decoded):
|
||
|
"""
|
||
|
Checks that dict has only the appropriate keys for orient='split'.
|
||
|
"""
|
||
|
bad_keys = set(decoded.keys()).difference(set(self._split_keys))
|
||
|
if bad_keys:
|
||
|
bad_keys_joined = ", ".join(bad_keys)
|
||
|
raise ValueError(f"JSON data had unexpected key(s): {bad_keys_joined}")
|
||
|
|
||
|
def parse(self):
|
||
|
|
||
|
# try numpy
|
||
|
numpy = self.numpy
|
||
|
if numpy:
|
||
|
self._parse_numpy()
|
||
|
|
||
|
else:
|
||
|
self._parse_no_numpy()
|
||
|
|
||
|
if self.obj is None:
|
||
|
return None
|
||
|
if self.convert_axes:
|
||
|
self._convert_axes()
|
||
|
self._try_convert_types()
|
||
|
return self.obj
|
||
|
|
||
|
def _parse_numpy(self):
|
||
|
raise AbstractMethodError(self)
|
||
|
|
||
|
def _parse_no_numpy(self):
|
||
|
raise AbstractMethodError(self)
|
||
|
|
||
|
def _convert_axes(self):
|
||
|
"""
|
||
|
Try to convert axes.
|
||
|
"""
|
||
|
obj = self.obj
|
||
|
assert obj is not None # for mypy
|
||
|
for axis_name in obj._AXIS_ORDERS:
|
||
|
new_axis, result = self._try_convert_data(
|
||
|
name=axis_name,
|
||
|
data=obj._get_axis(axis_name),
|
||
|
use_dtypes=False,
|
||
|
convert_dates=True,
|
||
|
)
|
||
|
if result:
|
||
|
setattr(self.obj, axis_name, new_axis)
|
||
|
|
||
|
def _try_convert_types(self):
|
||
|
raise AbstractMethodError(self)
|
||
|
|
||
|
def _try_convert_data(self, name, data, use_dtypes=True, convert_dates=True):
|
||
|
"""
|
||
|
Try to parse a ndarray like into a column by inferring dtype.
|
||
|
"""
|
||
|
# don't try to coerce, unless a force conversion
|
||
|
if use_dtypes:
|
||
|
if not self.dtype:
|
||
|
if all(notna(data)):
|
||
|
return data, False
|
||
|
return data.fillna(np.nan), True
|
||
|
|
||
|
elif self.dtype is True:
|
||
|
pass
|
||
|
else:
|
||
|
# dtype to force
|
||
|
dtype = (
|
||
|
self.dtype.get(name) if isinstance(self.dtype, dict) else self.dtype
|
||
|
)
|
||
|
if dtype is not None:
|
||
|
try:
|
||
|
dtype = np.dtype(dtype)
|
||
|
return data.astype(dtype), True
|
||
|
except (TypeError, ValueError):
|
||
|
return data, False
|
||
|
|
||
|
if convert_dates:
|
||
|
new_data, result = self._try_convert_to_date(data)
|
||
|
if result:
|
||
|
return new_data, True
|
||
|
|
||
|
result = False
|
||
|
|
||
|
if data.dtype == "object":
|
||
|
|
||
|
# try float
|
||
|
try:
|
||
|
data = data.astype("float64")
|
||
|
result = True
|
||
|
except (TypeError, ValueError):
|
||
|
pass
|
||
|
|
||
|
if data.dtype.kind == "f":
|
||
|
|
||
|
if data.dtype != "float64":
|
||
|
|
||
|
# coerce floats to 64
|
||
|
try:
|
||
|
data = data.astype("float64")
|
||
|
result = True
|
||
|
except (TypeError, ValueError):
|
||
|
pass
|
||
|
|
||
|
# don't coerce 0-len data
|
||
|
if len(data) and (data.dtype == "float" or data.dtype == "object"):
|
||
|
|
||
|
# coerce ints if we can
|
||
|
try:
|
||
|
new_data = data.astype("int64")
|
||
|
if (new_data == data).all():
|
||
|
data = new_data
|
||
|
result = True
|
||
|
except (TypeError, ValueError, OverflowError):
|
||
|
pass
|
||
|
|
||
|
# coerce ints to 64
|
||
|
if data.dtype == "int":
|
||
|
|
||
|
# coerce floats to 64
|
||
|
try:
|
||
|
data = data.astype("int64")
|
||
|
result = True
|
||
|
except (TypeError, ValueError):
|
||
|
pass
|
||
|
|
||
|
return data, result
|
||
|
|
||
|
def _try_convert_to_date(self, data):
|
||
|
"""
|
||
|
Try to parse a ndarray like into a date column.
|
||
|
|
||
|
Try to coerce object in epoch/iso formats and integer/float in epoch
|
||
|
formats. Return a boolean if parsing was successful.
|
||
|
"""
|
||
|
# no conversion on empty
|
||
|
if not len(data):
|
||
|
return data, False
|
||
|
|
||
|
new_data = data
|
||
|
if new_data.dtype == "object":
|
||
|
try:
|
||
|
new_data = data.astype("int64")
|
||
|
except (TypeError, ValueError, OverflowError):
|
||
|
pass
|
||
|
|
||
|
# ignore numbers that are out of range
|
||
|
if issubclass(new_data.dtype.type, np.number):
|
||
|
in_range = (
|
||
|
isna(new_data._values)
|
||
|
| (new_data > self.min_stamp)
|
||
|
| (new_data._values == iNaT)
|
||
|
)
|
||
|
if not in_range.all():
|
||
|
return data, False
|
||
|
|
||
|
date_units = (self.date_unit,) if self.date_unit else self._STAMP_UNITS
|
||
|
for date_unit in date_units:
|
||
|
try:
|
||
|
new_data = to_datetime(new_data, errors="raise", unit=date_unit)
|
||
|
except (ValueError, OverflowError, TypeError):
|
||
|
continue
|
||
|
return new_data, True
|
||
|
return data, False
|
||
|
|
||
|
def _try_convert_dates(self):
|
||
|
raise AbstractMethodError(self)
|
||
|
|
||
|
|
||
|
class SeriesParser(Parser):
|
||
|
_default_orient = "index"
|
||
|
_split_keys = ("name", "index", "data")
|
||
|
|
||
|
def _parse_no_numpy(self):
|
||
|
data = loads(self.json, precise_float=self.precise_float)
|
||
|
|
||
|
if self.orient == "split":
|
||
|
decoded = {str(k): v for k, v in data.items()}
|
||
|
self.check_keys_split(decoded)
|
||
|
self.obj = create_series_with_explicit_dtype(**decoded)
|
||
|
else:
|
||
|
self.obj = create_series_with_explicit_dtype(data, dtype_if_empty=object)
|
||
|
|
||
|
def _parse_numpy(self):
|
||
|
load_kwargs = {
|
||
|
"dtype": None,
|
||
|
"numpy": True,
|
||
|
"precise_float": self.precise_float,
|
||
|
}
|
||
|
if self.orient in ["columns", "index"]:
|
||
|
load_kwargs["labelled"] = True
|
||
|
loads_ = functools.partial(loads, **load_kwargs)
|
||
|
data = loads_(self.json)
|
||
|
|
||
|
if self.orient == "split":
|
||
|
decoded = {str(k): v for k, v in data.items()}
|
||
|
self.check_keys_split(decoded)
|
||
|
self.obj = create_series_with_explicit_dtype(**decoded)
|
||
|
elif self.orient in ["columns", "index"]:
|
||
|
# error: "create_series_with_explicit_dtype"
|
||
|
# gets multiple values for keyword argument "dtype_if_empty
|
||
|
self.obj = create_series_with_explicit_dtype(
|
||
|
*data, dtype_if_empty=object
|
||
|
) # type:ignore[misc]
|
||
|
else:
|
||
|
self.obj = create_series_with_explicit_dtype(data, dtype_if_empty=object)
|
||
|
|
||
|
def _try_convert_types(self):
|
||
|
if self.obj is None:
|
||
|
return
|
||
|
obj, result = self._try_convert_data(
|
||
|
"data", self.obj, convert_dates=self.convert_dates
|
||
|
)
|
||
|
if result:
|
||
|
self.obj = obj
|
||
|
|
||
|
|
||
|
class FrameParser(Parser):
|
||
|
_default_orient = "columns"
|
||
|
_split_keys = ("columns", "index", "data")
|
||
|
|
||
|
def _parse_numpy(self):
|
||
|
|
||
|
json = self.json
|
||
|
orient = self.orient
|
||
|
|
||
|
if orient == "columns":
|
||
|
args = loads(
|
||
|
json,
|
||
|
dtype=None,
|
||
|
numpy=True,
|
||
|
labelled=True,
|
||
|
precise_float=self.precise_float,
|
||
|
)
|
||
|
if len(args):
|
||
|
args = (args[0].T, args[2], args[1])
|
||
|
self.obj = DataFrame(*args)
|
||
|
elif orient == "split":
|
||
|
decoded = loads(
|
||
|
json, dtype=None, numpy=True, precise_float=self.precise_float
|
||
|
)
|
||
|
decoded = {str(k): v for k, v in decoded.items()}
|
||
|
self.check_keys_split(decoded)
|
||
|
self.obj = DataFrame(**decoded)
|
||
|
elif orient == "values":
|
||
|
self.obj = DataFrame(
|
||
|
loads(json, dtype=None, numpy=True, precise_float=self.precise_float)
|
||
|
)
|
||
|
else:
|
||
|
self.obj = DataFrame(
|
||
|
*loads(
|
||
|
json,
|
||
|
dtype=None,
|
||
|
numpy=True,
|
||
|
labelled=True,
|
||
|
precise_float=self.precise_float,
|
||
|
)
|
||
|
)
|
||
|
|
||
|
def _parse_no_numpy(self):
|
||
|
|
||
|
json = self.json
|
||
|
orient = self.orient
|
||
|
|
||
|
if orient == "columns":
|
||
|
self.obj = DataFrame(
|
||
|
loads(json, precise_float=self.precise_float), dtype=None
|
||
|
)
|
||
|
elif orient == "split":
|
||
|
decoded = {
|
||
|
str(k): v
|
||
|
for k, v in loads(json, precise_float=self.precise_float).items()
|
||
|
}
|
||
|
self.check_keys_split(decoded)
|
||
|
self.obj = DataFrame(dtype=None, **decoded)
|
||
|
elif orient == "index":
|
||
|
self.obj = DataFrame.from_dict(
|
||
|
loads(json, precise_float=self.precise_float),
|
||
|
dtype=None,
|
||
|
orient="index",
|
||
|
)
|
||
|
elif orient == "table":
|
||
|
self.obj = parse_table_schema(json, precise_float=self.precise_float)
|
||
|
else:
|
||
|
self.obj = DataFrame(
|
||
|
loads(json, precise_float=self.precise_float), dtype=None
|
||
|
)
|
||
|
|
||
|
def _process_converter(self, f, filt=None):
|
||
|
"""
|
||
|
Take a conversion function and possibly recreate the frame.
|
||
|
"""
|
||
|
if filt is None:
|
||
|
filt = lambda col, c: True
|
||
|
|
||
|
obj = self.obj
|
||
|
assert obj is not None # for mypy
|
||
|
|
||
|
needs_new_obj = False
|
||
|
new_obj = {}
|
||
|
for i, (col, c) in enumerate(obj.items()):
|
||
|
if filt(col, c):
|
||
|
new_data, result = f(col, c)
|
||
|
if result:
|
||
|
c = new_data
|
||
|
needs_new_obj = True
|
||
|
new_obj[i] = c
|
||
|
|
||
|
if needs_new_obj:
|
||
|
|
||
|
# possibly handle dup columns
|
||
|
new_frame = DataFrame(new_obj, index=obj.index)
|
||
|
new_frame.columns = obj.columns
|
||
|
self.obj = new_frame
|
||
|
|
||
|
def _try_convert_types(self):
|
||
|
if self.obj is None:
|
||
|
return
|
||
|
if self.convert_dates:
|
||
|
self._try_convert_dates()
|
||
|
|
||
|
self._process_converter(
|
||
|
lambda col, c: self._try_convert_data(col, c, convert_dates=False)
|
||
|
)
|
||
|
|
||
|
def _try_convert_dates(self):
|
||
|
if self.obj is None:
|
||
|
return
|
||
|
|
||
|
# our columns to parse
|
||
|
convert_dates = self.convert_dates
|
||
|
if convert_dates is True:
|
||
|
convert_dates = []
|
||
|
convert_dates = set(convert_dates)
|
||
|
|
||
|
def is_ok(col) -> bool:
|
||
|
"""
|
||
|
Return if this col is ok to try for a date parse.
|
||
|
"""
|
||
|
if not isinstance(col, str):
|
||
|
return False
|
||
|
|
||
|
col_lower = col.lower()
|
||
|
if (
|
||
|
col_lower.endswith("_at")
|
||
|
or col_lower.endswith("_time")
|
||
|
or col_lower == "modified"
|
||
|
or col_lower == "date"
|
||
|
or col_lower == "datetime"
|
||
|
or col_lower.startswith("timestamp")
|
||
|
):
|
||
|
return True
|
||
|
return False
|
||
|
|
||
|
self._process_converter(
|
||
|
lambda col, c: self._try_convert_to_date(c),
|
||
|
lambda col, c: (
|
||
|
(self.keep_default_dates and is_ok(col)) or col in convert_dates
|
||
|
),
|
||
|
)
|