from collections.abc import Mapping, Sequence
from typing import TYPE_CHECKING, Any, Unpack
from ..offline.types import PlaceholderTranslations, SourcePlaceholderTranslations
from ..translator_typing import AbstractFetcherParams
from ..types import ID, IdType, SourceType
from ._abstract_fetcher import AbstractFetcher
from .types import FetchInstruction
if TYPE_CHECKING:
import pandas
[docs]
class MemoryFetcher(AbstractFetcher[SourceType, IdType]):
"""Fetch from memory.
This is essentially a thin wrapper for the :class:`.PlaceholderTranslations` class.
Args:
data: A dict ``{source: PlaceholderTranslations}`` to fetch from.
return_all: If ``False``, return only the requested IDs and placeholders.
**kwargs: See :class:`.AbstractFetcher`.
"""
def __init__(
self,
data: (
SourcePlaceholderTranslations[SourceType]
| Mapping[SourceType, PlaceholderTranslations[SourceType]]
| Mapping[SourceType, "pandas.DataFrame"]
| Mapping[SourceType, Mapping[str, Sequence[Any]]]
),
return_all: bool = True,
**kwargs: Unpack[AbstractFetcherParams[SourceType, IdType]],
) -> None:
super().__init__(**kwargs)
self._data = {
source: pht
if isinstance(pht, PlaceholderTranslations)
else PlaceholderTranslations[SourceType].make(source, pht)
for source, pht in data.items()
}
self._return_all = return_all
@property
def return_all(self) -> bool:
"""If ``True``, :meth:`fetch_translations` will filter by ID."""
return self._return_all
def _initialize_sources(self, task_id: int) -> dict[SourceType, list[str]]: # noqa: ARG002
return {source: list(pht.placeholders) for source, pht in self._data.items()}
[docs]
def fetch_translations(self, instr: FetchInstruction[SourceType, IdType]) -> PlaceholderTranslations[SourceType]:
ret = self._data[instr.source]
if self.return_all:
return ret
placeholder_indices = [
ret.placeholders.index(placeholder)
for placeholder in instr.placeholders # requested
if placeholder in ret.placeholders # available
]
if instr.ids is None:
records = tuple(tuple(record[i] for i in placeholder_indices) for record in ret.records)
else:
ids = set(instr.ids)
records = tuple(
tuple(record[i] for i in placeholder_indices)
for record in ret.records
if record[ret.id_pos] in ids # crash on missing IDs
)
placeholders = tuple(ret.placeholders[i] for i in placeholder_indices)
id_pos = placeholders.index(ID) if ID in placeholders else -1
return PlaceholderTranslations(instr.source, placeholders, records, id_pos)
def __str__(self) -> str:
class NoSources:
def __repr__(self) -> str:
return "<no sources>"
sources = self.sources or NoSources()
return_all = self.return_all
return f"{type(self).__name__}({sources=}, {return_all=})"
