322 lines
12 KiB
Python

"""Hybrid retrieval for historical anomaly cases."""
from __future__ import annotations
import asyncio
import logging
import re
from dataclasses import dataclass
from typing import Any
import httpx
from sqlalchemy import select
from sqlalchemy import text as sql_text
from sqlalchemy.ext.asyncio import AsyncSession
from app.core.config import get_settings
from app.models.entities import AnomalyCase
from app.schemas.risk_prediction import SimilarCase
from app.services.supplier_identity import resolve_supplier
logger = logging.getLogger("dieya_risk_prediction.rag")
_embedding_semaphore = asyncio.Semaphore(1)
@dataclass(frozen=True, slots=True)
class RetrievedCase:
case: SimilarCase
score: float
case_id: int
class AnomalyCaseRAG:
"""Retrieve historical cases with business, text, and optional vector signals."""
def __init__(
self,
session: AsyncSession,
*,
top_k: int | None = None,
transport: httpx.AsyncBaseTransport | None = None,
) -> None:
self.session = session
self.top_k = top_k or get_settings().rag_top_k
self.transport = transport
async def search(
self,
*,
query: str,
category: str | None = None,
material: str | None = None,
supplier: str | None = None,
factory: str | None = None,
stage: str | None = None,
anomaly_type: str | None = None,
rows: list[dict[str, Any]] | None = None,
) -> list[RetrievedCase]:
identity = await resolve_supplier(self.session, supplier)
supplier_match = (
identity.short_name or identity.aliases[0]
if identity
else supplier
)
terms = self._terms(query, category, material, supplier, factory, stage, anomaly_type)
rows = rows if rows is not None else await self._load_rows(
query,
category=category,
material=material,
supplier=supplier,
factory=factory,
stage=stage,
anomaly_type=anomaly_type,
)
ranked = [
RetrievedCase(
case=self._to_case(row),
score=self._score(
row,
query=query,
category=category,
material=material,
supplier=supplier_match,
factory=factory,
stage=stage,
anomaly_type=anomaly_type,
terms=terms,
),
case_id=int(row["id"]),
)
for row in rows
]
ranked = [item for item in ranked if item.score > 0]
ranked.sort(key=lambda item: (item.score, item.case_id), reverse=True)
for item in ranked[: self.top_k]:
vector_similarity = next(
(
float(row["vector_score"])
for row in rows
if int(row["id"]) == item.case_id and row.get("vector_score") is not None
),
None,
)
item.case.similarity = round(
max(0.0, min(1.0, vector_similarity if vector_similarity is not None else item.score / 100)),
3,
)
return ranked[: self.top_k]
async def _load_rows(
self,
query: str,
*,
category: str | None,
material: str | None,
supplier: str | None,
factory: str | None,
stage: str | None,
anomaly_type: str | None,
) -> list[dict[str, Any]]:
fields = (
AnomalyCase.id,
AnomalyCase.date,
AnomalyCase.product_name,
AnomalyCase.product_category,
AnomalyCase.material_type,
AnomalyCase.supplier,
AnomalyCase.factory,
AnomalyCase.stage_new,
AnomalyCase.anomaly_type,
AnomalyCase.description,
AnomalyCase.solution,
AnomalyCase.root_cause,
AnomalyCase.defect_level,
AnomalyCase.result,
)
vector_ready = await self._vector_column_ready()
has_vectors = await self._has_stored_vectors() if vector_ready else False
vector = await self._query_embedding(query) if has_vectors else None
if vector is None:
return [dict(row) for row in (await self.session.execute(select(*fields).limit(5000))).mappings().all()]
vector_literal = "[" + ",".join(str(float(value)) for value in vector) + "]"
statement = sql_text(
"""
SELECT id, date, product_name, product_category, material_type, supplier,
factory, stage_new, anomaly_type, description, solution, root_cause,
defect_level, result, 1 - (embedding_vector <=> CAST(:embedding AS halfvec)) AS vector_score
FROM anomaly_cases
WHERE embedding_vector IS NOT NULL
ORDER BY embedding_vector <=> CAST(:embedding AS halfvec)
LIMIT 5000
"""
)
result = await self.session.execute(statement, {"embedding": vector_literal})
rows = [dict(row) for row in result.mappings().all()]
if rows:
return rows
return [dict(row) for row in (await self.session.execute(select(*fields).limit(5000))).mappings().all()]
async def _vector_column_ready(self) -> bool:
try:
result = await self.session.execute(
sql_text(
"""
SELECT EXISTS (
SELECT 1
FROM information_schema.columns
WHERE table_name = 'anomaly_cases'
AND column_name = 'embedding_vector'
AND udt_name IN ('vector', 'halfvec')
)
"""
)
)
return bool(result.scalar())
except Exception: # noqa: BLE001 - a missing optional extension uses lexical retrieval
await self.session.rollback()
return False
async def _query_embedding(self, query: str) -> list[float] | None:
settings = get_settings()
api_key = (
settings.rag_embedding_api_key.get_secret_value()
if settings.rag_embedding_api_key
else settings.llm_api_key.get_secret_value() if settings.llm_api_key else ""
)
base_url = settings.rag_embedding_base_url or settings.llm_base_url
if not api_key or not base_url:
return None
endpoint = f"{base_url.rstrip('/')}/embeddings"
if not base_url.rstrip("/").endswith("/v1"):
endpoint = f"{base_url.rstrip('/')}/v1/embeddings"
timeout = httpx.Timeout(
settings.rag_embedding_timeout_seconds,
connect=min(5, settings.rag_embedding_timeout_seconds),
)
try:
async with _embedding_semaphore:
async with httpx.AsyncClient(timeout=timeout, transport=self.transport) as client:
response = await client.post(
endpoint,
headers={"Authorization": f"Bearer {api_key}", "Content-Type": "application/json"},
json={"model": settings.rag_embedding_model, "input": query[:2000]},
)
response.raise_for_status()
body = response.json()
embedding = (body.get("data") or [{}])[0].get("embedding")
if not isinstance(embedding, list) or len(embedding) != settings.rag_embedding_dimensions:
return None
return [float(value) for value in embedding]
except (httpx.HTTPError, ValueError, TypeError, KeyError) as exc:
logger.warning(
"RAG embedding request failed error=%s; using lexical retrieval",
exc.__class__.__name__,
)
return None
async def _has_stored_vectors(self) -> bool:
"""Avoid a paid/network embedding call until case vectors exist."""
try:
result = await self.session.execute(
sql_text(
"SELECT EXISTS ("
"SELECT 1 FROM anomaly_cases WHERE embedding_vector IS NOT NULL LIMIT 1"
")"
)
)
return bool(result.scalar())
except Exception: # noqa: BLE001 - lexical retrieval is the safe fallback
await self.session.rollback()
return False
@staticmethod
def _terms(*values: str | None) -> list[str]:
terms: list[str] = []
for value in values:
if not value:
continue
cleaned = " ".join(str(value).strip().lower().split())
runs = re.findall(r"[a-z0-9]+|[\u4e00-\u9fff]{2,}", cleaned)
terms.extend(runs)
for run in runs:
if re.fullmatch(r"[\u4e00-\u9fff]+", run) and len(run) > 3:
terms.extend(
run[index : index + size]
for size in (2, 3, 4)
for index in range(len(run) - size + 1)
)
return list(dict.fromkeys(term for term in terms if len(term) > 1))
@classmethod
def _score(
cls,
row: dict[str, Any],
*,
query: str,
category: str | None,
material: str | None,
supplier: str | None,
factory: str | None,
stage: str | None,
anomaly_type: str | None,
terms: list[str],
) -> float:
score = 0.0
score += cls._field_score(row.get("product_category"), category, 7)
score += cls._field_score(row.get("product_name"), category, 5)
score += cls._field_score(row.get("material_type"), material, 7)
score += cls._field_score(row.get("supplier"), supplier, 6)
score += cls._field_score(row.get("factory"), factory, 6)
score += cls._field_score(row.get("stage_new"), stage, 3)
score += cls._field_score(row.get("anomaly_type"), anomaly_type, 7)
vector_score = row.get("vector_score")
if vector_score is not None:
score += max(0.0, float(vector_score)) * 40
searchable = " ".join(str(row.get(key) or "") for key in (
"product_name",
"product_category",
"material_type",
"anomaly_type",
"description",
"root_cause",
"solution",
)).lower()
query_lower = query.lower().strip()
if query_lower and query_lower in searchable:
score += 8
score += min(12.0, sum(1 for term in terms if term in searchable) * 1.5)
if str(row.get("defect_level") or "").upper() == "A":
score += 1.0
return round(score, 2)
@staticmethod
def _field_score(actual: Any, expected: str | None, weight: float) -> float:
if not actual or not expected:
return 0.0
actual_text = str(actual).lower()
expected_text = str(expected).lower()
if actual_text == expected_text:
return weight
if expected_text in actual_text or actual_text in expected_text:
return weight * 0.7
return 0.0
@staticmethod
def _to_case(row: dict[str, Any]) -> SimilarCase:
return SimilarCase(
case_id=int(row["id"]) if row.get("id") is not None else None,
date=row.get("date").isoformat() if row.get("date") else None,
product=row.get("product_name") or row.get("product_category") or "未命名产品",
category=row.get("product_category"),
material=row.get("material_type"),
anomaly_type=row.get("anomaly_type"),
description=row.get("description"),
root_cause=row.get("root_cause"),
defect_level=row.get("defect_level"),
result=row.get("result"),
problem=(row.get("anomaly_type") or row.get("description") or "历史异常未填写"),
solution=(row.get("solution") or row.get("root_cause") or "请查看原始案例记录"),
)