spaCy/spacy/ml/models/entity_linker.py
2023-06-26 11:41:03 +02:00

151 lines
5.0 KiB
Python

from pathlib import Path
from typing import Callable, Iterable, List, Optional, Tuple
from thinc.api import (
Linear,
Maxout,
Model,
Ragged,
chain,
list2ragged,
reduce_mean,
residual,
tuplify,
)
from thinc.types import Floats2d
from ...errors import Errors
from ...kb import Candidate, InMemoryLookupKB, KnowledgeBase
from ...tokens import Doc, Span, SpanGroup
from ...util import registry
from ...vocab import Vocab
from ..extract_spans import extract_spans
@registry.architectures("spacy.EntityLinker.v2")
def build_nel_encoder(
tok2vec: Model, nO: Optional[int] = None
) -> Model[List[Doc], Floats2d]:
with Model.define_operators({">>": chain, "&": tuplify}):
token_width = tok2vec.maybe_get_dim("nO")
output_layer = Linear(nO=nO, nI=token_width)
model = (
((tok2vec >> list2ragged()) & build_span_maker())
>> extract_spans()
>> reduce_mean()
>> residual(Maxout(nO=token_width, nI=token_width, nP=2, dropout=0.0)) # type: ignore
>> output_layer
)
model.set_ref("output_layer", output_layer)
model.set_ref("tok2vec", tok2vec)
# flag to show this isn't legacy
model.attrs["include_span_maker"] = True
return model
def build_span_maker(n_sents: int = 0) -> Model:
model: Model = Model("span_maker", forward=span_maker_forward)
model.attrs["n_sents"] = n_sents
return model
def span_maker_forward(model, docs: List[Doc], is_train) -> Tuple[Ragged, Callable]:
ops = model.ops
n_sents = model.attrs["n_sents"]
candidates = []
for doc in docs:
cands = []
try:
sentences = [s for s in doc.sents]
except ValueError:
# no sentence info, normal in initialization
for tok in doc:
tok.is_sent_start = tok.i == 0
sentences = [doc[:]]
for ent in doc.ents:
try:
# find the sentence in the list of sentences.
sent_index = sentences.index(ent.sent)
except AttributeError:
# Catch the exception when ent.sent is None and provide a user-friendly warning
raise RuntimeError(Errors.E030) from None
# get n previous sentences, if there are any
start_sentence = max(0, sent_index - n_sents)
# get n posterior sentences, or as many < n as there are
end_sentence = min(len(sentences) - 1, sent_index + n_sents)
# get token positions
start_token = sentences[start_sentence].start
end_token = sentences[end_sentence].end
# save positions for extraction
cands.append((start_token, end_token))
candidates.append(ops.asarray2i(cands))
lengths = model.ops.asarray1i([len(cands) for cands in candidates])
out = Ragged(model.ops.flatten(candidates), lengths)
# because this is just rearranging docs, the backprop does nothing
return out, lambda x: []
@registry.misc("spacy.KBFromFile.v1")
def load_kb(
kb_path: Path,
) -> Callable[[Vocab], KnowledgeBase]:
def kb_from_file(vocab: Vocab):
kb = InMemoryLookupKB(vocab, entity_vector_length=1)
kb.from_disk(kb_path)
return kb
return kb_from_file
@registry.misc("spacy.EmptyKB.v2")
def empty_kb_for_config() -> Callable[[Vocab, int], KnowledgeBase]:
def empty_kb_factory(vocab: Vocab, entity_vector_length: int):
return InMemoryLookupKB(vocab=vocab, entity_vector_length=entity_vector_length)
return empty_kb_factory
@registry.misc("spacy.EmptyKB.v1")
def empty_kb(
entity_vector_length: int,
) -> Callable[[Vocab], KnowledgeBase]:
def empty_kb_factory(vocab: Vocab):
return InMemoryLookupKB(vocab=vocab, entity_vector_length=entity_vector_length)
return empty_kb_factory
@registry.misc("spacy.CandidateGenerator.v1")
def create_candidates() -> Callable[[KnowledgeBase, Span], Iterable[Candidate]]:
return get_candidates
@registry.misc("spacy.CandidateBatchGenerator.v1")
def create_candidates_batch() -> Callable[
[KnowledgeBase, SpanGroup], Iterable[Iterable[Candidate]]
]:
return get_candidates_batch
def get_candidates(kb: KnowledgeBase, mention: Span) -> Iterable[Candidate]:
"""
Return candidate entities for a given mention and fetching appropriate entries from the index.
kb (KnowledgeBase): Knowledge base to query.
mention (Span): Entity mention for which to identify candidates.
RETURNS (Iterable[Candidate]): Identified candidates.
"""
return kb.get_candidates(mention)
def get_candidates_batch(
kb: KnowledgeBase, mentions: SpanGroup
) -> Iterable[Iterable[Candidate]]:
"""
Return candidate entities for the given mentions and fetching appropriate entries from the index.
kb (KnowledgeBase): Knowledge base to query.
mentions (SpanGroup): Entity mentions for which to identify candidates.
RETURNS (Iterable[Iterable[Candidate]]): Identified candidates.
"""
return kb.get_candidates_batch(mentions)