dify/api/core/index/vector_index.py
2023-05-22 17:39:28 +08:00

137 lines
4.8 KiB
Python

import json
import logging
from typing import List, Optional
from llama_index.data_structs import Node
from requests import ReadTimeout
from sqlalchemy.exc import IntegrityError
from tenacity import retry, stop_after_attempt, retry_if_exception_type
from core.index.index_builder import IndexBuilder
from core.vector_store.base import BaseGPTVectorStoreIndex
from extensions.ext_vector_store import vector_store
from extensions.ext_database import db
from models.dataset import Dataset, Embedding
class VectorIndex:
def __init__(self, dataset: Dataset):
self._dataset = dataset
def add_nodes(self, nodes: List[Node], duplicate_check: bool = False):
if not self._dataset.index_struct_dict:
index_id = "Vector_index_" + self._dataset.id.replace("-", "_")
self._dataset.index_struct = json.dumps(vector_store.to_index_struct(index_id))
db.session.commit()
service_context = IndexBuilder.get_default_service_context(tenant_id=self._dataset.tenant_id)
index = vector_store.get_index(
service_context=service_context,
index_struct=self._dataset.index_struct_dict
)
if duplicate_check:
nodes = self._filter_duplicate_nodes(index, nodes)
embedding_queue_nodes = []
embedded_nodes = []
for node in nodes:
node_hash = node.doc_hash
# if node hash in cached embedding tables, use cached embedding
embedding = db.session.query(Embedding).filter_by(hash=node_hash).first()
if embedding:
node.embedding = embedding.get_embedding()
embedded_nodes.append(node)
else:
embedding_queue_nodes.append(node)
if embedding_queue_nodes:
embedding_results = index._get_node_embedding_results(
embedding_queue_nodes,
set(),
)
# pre embed nodes for cached embedding
for embedding_result in embedding_results:
node = embedding_result.node
node.embedding = embedding_result.embedding
try:
embedding = Embedding(hash=node.doc_hash)
embedding.set_embedding(node.embedding)
db.session.add(embedding)
db.session.commit()
except IntegrityError:
db.session.rollback()
continue
except:
logging.exception('Failed to add embedding to db')
continue
embedded_nodes.append(node)
self.index_insert_nodes(index, embedded_nodes)
@retry(reraise=True, retry=retry_if_exception_type(ReadTimeout), stop=stop_after_attempt(3))
def index_insert_nodes(self, index: BaseGPTVectorStoreIndex, nodes: List[Node]):
index.insert_nodes(nodes)
def del_nodes(self, node_ids: List[str]):
if not self._dataset.index_struct_dict:
return
service_context = IndexBuilder.get_fake_llm_service_context(tenant_id=self._dataset.tenant_id)
index = vector_store.get_index(
service_context=service_context,
index_struct=self._dataset.index_struct_dict
)
for node_id in node_ids:
self.index_delete_node(index, node_id)
@retry(reraise=True, retry=retry_if_exception_type(ReadTimeout), stop=stop_after_attempt(3))
def index_delete_node(self, index: BaseGPTVectorStoreIndex, node_id: str):
index.delete_node(node_id)
def del_doc(self, doc_id: str):
if not self._dataset.index_struct_dict:
return
service_context = IndexBuilder.get_fake_llm_service_context(tenant_id=self._dataset.tenant_id)
index = vector_store.get_index(
service_context=service_context,
index_struct=self._dataset.index_struct_dict
)
self.index_delete_doc(index, doc_id)
@retry(reraise=True, retry=retry_if_exception_type(ReadTimeout), stop=stop_after_attempt(3))
def index_delete_doc(self, index: BaseGPTVectorStoreIndex, doc_id: str):
index.delete(doc_id)
@property
def query_index(self) -> Optional[BaseGPTVectorStoreIndex]:
if not self._dataset.index_struct_dict:
return None
service_context = IndexBuilder.get_default_service_context(tenant_id=self._dataset.tenant_id)
return vector_store.get_index(
service_context=service_context,
index_struct=self._dataset.index_struct_dict
)
def _filter_duplicate_nodes(self, index: BaseGPTVectorStoreIndex, nodes: List[Node]) -> List[Node]:
for node in nodes:
node_id = node.doc_id
exists_duplicate_node = index.exists_by_node_id(node_id)
if exists_duplicate_node:
nodes.remove(node)
return nodes