spaCy/spacy/tokens/_dict_proxies.py

111 lines
4.4 KiB
Python

import warnings
import weakref
from collections import UserDict
from typing import TYPE_CHECKING, Dict, Iterable, List, Optional, Tuple, Union
import srsly
from ..errors import Errors, Warnings
from .span_group import SpanGroup
if TYPE_CHECKING:
# This lets us add type hints for mypy etc. without causing circular imports
from .doc import Doc # noqa: F401
from .span import Span # noqa: F401
# Why inherit from UserDict instead of dict here?
# Well, the 'dict' class doesn't necessarily delegate everything nicely,
# for performance reasons. The UserDict is slower but better behaved.
# See https://treyhunner.com/2019/04/why-you-shouldnt-inherit-from-list-and-dict-in-python/
class SpanGroups(UserDict):
"""A dict-like proxy held by the Doc, to control access to span groups."""
_EMPTY_BYTES = srsly.msgpack_dumps([])
def __init__(
self, doc: "Doc", items: Iterable[Tuple[str, SpanGroup]] = tuple()
) -> None:
self.doc_ref = weakref.ref(doc)
UserDict.__init__(self, items) # type: ignore[arg-type]
def __setitem__(self, key: str, value: Union[SpanGroup, Iterable["Span"]]) -> None:
if not isinstance(value, SpanGroup):
value = self._make_span_group(key, value)
assert value.doc is self.doc_ref()
UserDict.__setitem__(self, key, value)
def _make_span_group(self, name: str, spans: Iterable["Span"]) -> SpanGroup:
doc = self._ensure_doc()
return SpanGroup(doc, name=name, spans=spans)
def copy(self, doc: Optional["Doc"] = None) -> "SpanGroups":
if doc is None:
doc = self._ensure_doc()
data_copy = ((k, v.copy(doc=doc)) for k, v in self.items())
return SpanGroups(doc, items=data_copy)
def setdefault(self, key, default=None):
if not isinstance(default, SpanGroup):
if default is None:
spans = []
else:
spans = default
default = self._make_span_group(key, spans)
return super().setdefault(key, default=default)
def to_bytes(self) -> bytes:
# We serialize this as a dict in order to track the key(s) a SpanGroup
# is a value of (in a backward- and forward-compatible way), since
# a SpanGroup can have a key that doesn't match its `.name` (See #10685)
if len(self) == 0:
return self._EMPTY_BYTES
msg: Dict[bytes, List[str]] = {}
for key, value in self.items():
msg.setdefault(value.to_bytes(), []).append(key)
return srsly.msgpack_dumps(msg)
def from_bytes(self, bytes_data: bytes) -> "SpanGroups":
# backwards-compatibility: bytes_data may be one of:
# b'', a serialized empty list, a serialized list of SpanGroup bytes
# or a serialized dict of SpanGroup bytes -> keys
msg = (
[]
if not bytes_data or bytes_data == self._EMPTY_BYTES
else srsly.msgpack_loads(bytes_data)
)
self.clear()
doc = self._ensure_doc()
if isinstance(msg, list):
# This is either the 1st version of `SpanGroups` serialization
# or there were no SpanGroups serialized
for value_bytes in msg:
group = SpanGroup(doc).from_bytes(value_bytes)
if group.name in self:
# Display a warning if `msg` contains `SpanGroup`s
# that have the same .name (attribute).
# Because, for `SpanGroups` serialized as lists,
# only 1 SpanGroup per .name is loaded. (See #10685)
warnings.warn(
Warnings.W120.format(
group_name=group.name, group_values=self[group.name]
)
)
self[group.name] = group
else:
for value_bytes, keys in msg.items():
group = SpanGroup(doc).from_bytes(value_bytes)
# Deserialize `SpanGroup`s as copies because it's possible for two
# different `SpanGroup`s (pre-serialization) to have the same bytes
# (since they can have the same `.name`).
self[keys[0]] = group
for key in keys[1:]:
self[key] = group.copy()
return self
def _ensure_doc(self) -> "Doc":
doc = self.doc_ref()
if doc is None:
raise ValueError(Errors.E866)
return doc