Files
eveAI/common/langchain/EveAIRetriever.py

80 lines
3.4 KiB
Python

from langchain_core.retrievers import BaseRetriever
from sqlalchemy import func, and_, or_
from sqlalchemy.exc import SQLAlchemyError
from pydantic import BaseModel, Field
from typing import Any, Dict
from flask import current_app
from datetime import date
from common.extensions import db
from common.models.document import Document, DocumentVersion, Embedding
class EveAIRetriever(BaseRetriever):
model_variables: Dict[str, Any] = Field(...)
def __init__(self, model_variables: Dict[str, Any]):
super().__init__()
current_app.logger.debug('Initializing EveAIRetriever')
self.model_variables = model_variables
current_app.logger.debug('EveAIRetriever initialized')
def _get_relevant_documents(self, query: str):
current_app.logger.debug(f'Retrieving relevant documents for query: {query}')
query_embedding = self._get_query_embedding(query)
db_class = self.model_variables['embedding_db_model']
similarity_threshold = self.model_variables['similarity_threshold']
k = self.model_variables['k']
try:
current_date = date.today()
# Subquery to find the latest version of each document
subquery = (
db.session.query(
DocumentVersion.doc_id,
func.max(DocumentVersion.id).label('latest_version_id')
)
.group_by(DocumentVersion.doc_id)
.subquery()
)
# Main query to filter embeddings
query_obj = (
db.session.query(db_class,
db_class.embedding.cosine_distance(query_embedding).label('distance'))
.join(DocumentVersion, db_class.doc_vers_id == DocumentVersion.id)
.join(Document, DocumentVersion.doc_id == Document.id)
.join(subquery, DocumentVersion.id == subquery.c.latest_version_id)
.filter(
or_(Document.valid_from.is_(None), Document.valid_from <= current_date),
or_(Document.valid_to.is_(None), Document.valid_to >= current_date),
db_class.embedding.cosine_distance(query_embedding) < similarity_threshold
)
.order_by('distance')
.limit(k)
)
# Print the generated SQL statement for debugging
current_app.logger.debug("SQL Statement:\n")
current_app.logger.debug(query_obj.statement.compile(compile_kwargs={"literal_binds": True}))
res = query_obj.all()
# current_app.rag_tuning_logger.debug(f'Retrieved {len(res)} relevant documents')
# current_app.rag_tuning_logger.debug(f'---------------------------------------')
result = []
for doc in res:
# current_app.rag_tuning_logger.debug(f'Document ID: {doc[0].id} - Distance: {doc[1]}\n')
# current_app.rag_tuning_logger.debug(f'Chunk: \n {doc[0].chunk}\n\n')
result.append(f'SOURCE: {doc[0].id}\n\n{doc[0].chunk}\n\n')
except SQLAlchemyError as e:
current_app.logger.error(f'Error retrieving relevant documents: {e}')
db.session.rollback()
return []
return result
def _get_query_embedding(self, query: str):
embedding_model = self.model_variables['embedding_model']
query_embedding = embedding_model.embed_query(query)
return query_embedding