feat: Add PGVector support

Added first working iteration of PGVector for cognee, some important funcionality is still missing, but the core is there. Also some refactoring will be necessary.

Feature: #COG-170
This commit is contained in:
Igor Ilic 2024-10-17 17:05:38 +02:00
parent 268396abdc
commit 9fbf2d857f
6 changed files with 145 additions and 92 deletions

View file

@ -14,9 +14,12 @@ from cognee.tasks.ingestion import get_dlt_destination
from cognee.modules.users.permissions.methods import give_permission_on_document
from cognee.modules.users.models import User
from cognee.modules.data.methods import create_dataset
from cognee.infrastructure.databases.relational import create_db_and_tables as create_relational_db_and_tables
from cognee.infrastructure.databases.vector import create_db_and_tables as create_vector_db_and_tables
async def add(data: Union[BinaryIO, List[BinaryIO], str, List[str]], dataset_name: str = "main_dataset", user: User = None):
await create_db_and_tables()
await create_relational_db_and_tables()
await create_vector_db_and_tables()
if isinstance(data, str):
if "data://" in data:

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@ -3,10 +3,12 @@ from cognee.modules.users.models import User
from cognee.modules.users.methods import get_default_user
from cognee.modules.pipelines import run_tasks, Task
from cognee.tasks.ingestion import save_data_to_storage, ingest_data
from cognee.infrastructure.databases.relational import create_db_and_tables
from cognee.infrastructure.databases.relational import create_db_and_tables as create_relational_db_and_tables
from cognee.infrastructure.databases.vector import create_db_and_tables as create_vector_db_and_tables
async def add(data: Union[BinaryIO, list[BinaryIO], str, list[str]], dataset_name: str = "main_dataset", user: User = None):
await create_db_and_tables()
await create_relational_db_and_tables()
await create_vector_db_and_tables()
if user is None:
user = await get_default_user()

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@ -4,3 +4,4 @@ from .models.CollectionConfig import CollectionConfig
from .vector_db_interface import VectorDBInterface
from .config import get_vectordb_config
from .get_vector_engine import get_vector_engine
from .create_db_and_tables import create_db_and_tables

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@ -0,0 +1,15 @@
from ..relational.ModelBase import Base
from .get_vector_engine import get_vector_engine, get_vectordb_config
from sqlalchemy import text
async def create_db_and_tables():
vector_config = get_vectordb_config()
vector_engine = get_vector_engine()
if vector_config.vector_engine_provider == "pgvector":
async with vector_engine.engine.begin() as connection:
if len(Base.metadata.tables.keys()) > 0:
await connection.run_sync(Base.metadata.create_all)
await connection.execute(text("CREATE EXTENSION IF NOT EXISTS vector;"))

View file

@ -42,7 +42,8 @@ def create_vector_engine(config: VectorConfig, embedding_engine):
# Get name of vector database
db_name = config["vector_db_name"]
connection_string = f"postgresql+asyncpg://{db_username}:{db_password}@{db_host}:{db_port}/{db_name}"
connection_string: str = f"postgresql+asyncpg://{db_username}:{db_password}@{db_host}:{db_port}/{db_name}"
return PGVectorAdapter(connection_string,
config["vector_db_key"],
embedding_engine

View file

@ -1,27 +1,35 @@
from typing import List, Optional, get_type_hints, Generic, TypeVar
import asyncio
from typing import List, Optional, get_type_hints, Any, Dict
from sqlalchemy import text, select
from sqlalchemy import JSON, Column, Table
from sqlalchemy.dialects.postgresql import ARRAY
from ..models.ScoredResult import ScoredResult
from ..vector_db_interface import VectorDBInterface, DataPoint
from sqlalchemy.orm import Mapped, mapped_column
from ..embeddings.EmbeddingEngine import EmbeddingEngine
from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine, async_sessionmaker
from sqlalchemy.orm import DeclarativeBase, mapped_column
from pgvector.sqlalchemy import Vector
from ...relational.sqlalchemy.SqlAlchemyAdapter import SQLAlchemyAdapter
from ...relational.ModelBase import Base
from datetime import datetime
# Define the models
class Base(DeclarativeBase):
pass
# TODO: Find better location for function
def serialize_datetime(data):
"""Recursively convert datetime objects in dictionaries/lists to ISO format."""
if isinstance(data, dict):
return {key: serialize_datetime(value) for key, value in data.items()}
elif isinstance(data, list):
return [serialize_datetime(item) for item in data]
elif isinstance(data, datetime):
return data.isoformat() # Convert datetime to ISO 8601 string
else:
return data
class PGVectorAdapter(SQLAlchemyAdapter, VectorDBInterface):
async def create_vector_extension(self):
async with self.get_async_session() as session:
await session.execute(text("CREATE EXTENSION IF NOT EXISTS vector"))
def __init__(self, connection_string: str,
def __init__(self, connection_string: str,
api_key: Optional[str],
embedding_engine: EmbeddingEngine
):
@ -29,121 +37,156 @@ class PGVectorAdapter(SQLAlchemyAdapter, VectorDBInterface):
self.embedding_engine = embedding_engine
self.db_uri: str = connection_string
self.engine = create_async_engine(connection_string)
self.engine = create_async_engine(self.db_uri, echo=True)
self.sessionmaker = async_sessionmaker(bind=self.engine, expire_on_commit=False)
self.create_vector_extension()
async def embed_data(self, data: list[str]) -> list[list[float]]:
return await self.embedding_engine.embed_text(data)
async def has_collection(self, collection_name: str) -> bool:
async with self.engine.begin() as connection:
collection_names = await connection.table_names()
return collection_name in collection_names
#TODO: Switch to using ORM instead of raw query
result = await connection.execute(
text("SELECT table_name FROM information_schema.tables WHERE table_schema = 'public';")
)
tables = result.fetchall()
for table in tables:
if collection_name == table[0]:
return True
return False
async def create_collection(self, collection_name: str, payload_schema = None):
data_point_types = get_type_hints(DataPoint)
vector_size = self.embedding_engine.get_vector_size()
class PGVectorDataPoint(Base):
id: Mapped[int] = mapped_column(data_point_types["id"], primary_key=True)
vector = mapped_column(Vector(vector_size))
payload: mapped_column(payload_schema)
if not await self.has_collection(collection_name):
class PGVectorDataPoint(Base):
__tablename__ = collection_name
__table_args__ = {'extend_existing': True}
# PGVector requires one column to be the primary key
primary_key: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
id: Mapped[data_point_types["id"]]
payload = Column(JSON)
vector = Column(Vector(vector_size))
def __init__(self, id, payload, vector):
self.id = id
self.payload = payload
self.vector = vector
async with self.engine.begin() as connection:
return await connection.create_table(
name = collection_name,
schema = PGVectorDataPoint,
exist_ok = True,
)
if len(Base.metadata.tables.keys()) > 0:
await connection.run_sync(Base.metadata.create_all, tables=[PGVectorDataPoint.__table__])
async def create_data_points(self, collection_name: str, data_points: List[DataPoint]):
async with self.engine.begin() as connection:
async with self.get_async_session() as session:
if not await self.has_collection(collection_name):
await self.create_collection(
collection_name,
collection_name = collection_name,
payload_schema = type(data_points[0].payload),
)
collection = await connection.open_table(collection_name)
data_vectors = await self.embed_data(
[data_point.get_embeddable_data() for data_point in data_points]
)
IdType = TypeVar("IdType")
PayloadSchema = TypeVar("PayloadSchema")
vector_size = self.embedding_engine.get_vector_size()
class PGVectorDataPoint(Base, Generic[IdType, PayloadSchema]):
id: Mapped[int] = mapped_column(IdType, primary_key=True)
vector = mapped_column(Vector(vector_size))
payload: mapped_column(PayloadSchema)
class PGVectorDataPoint(Base):
__tablename__ = collection_name
__table_args__ = {'extend_existing': True}
# PGVector requires one column to be the primary key
primary_key: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
id: Mapped[type(data_points[0].id)]
payload = Column(JSON)
vector = Column(Vector(vector_size))
def __init__(self, id, payload, vector):
self.id = id
self.payload = payload
self.vector = vector
pgvector_data_points = [
PGVectorDataPoint[type(data_point.id), type(data_point.payload)](
PGVectorDataPoint(
id = data_point.id,
vector = data_vectors[data_index],
payload = data_point.payload,
payload = serialize_datetime(data_point.payload.dict())
) for (data_index, data_point) in enumerate(data_points)
]
await collection.add(pgvector_data_points)
session.add_all(pgvector_data_points)
await session.commit()
async def retrieve(self, collection_name: str, data_point_ids: list[str]):
async with self.engine.begin() as connection:
collection = await connection.open_table(collection_name)
async def retrieve(self, collection_name: str, data_point_ids: List[str]):
async with AsyncSession(self.engine) as session:
try:
# Construct the SQL query
# TODO: Switch to using ORM instead of raw query
if len(data_point_ids) == 1:
query = text(f"SELECT * FROM {collection_name} WHERE id = :id")
result = await session.execute(query, {"id": data_point_ids[0]})
else:
query = text(f"SELECT * FROM {collection_name} WHERE id = ANY(:ids)")
result = await session.execute(query, {"ids": data_point_ids})
if len(data_point_ids) == 1:
results = await collection.query().where(f"id = '{data_point_ids[0]}'").to_pandas()
else:
results = await collection.query().where(f"id IN {tuple(data_point_ids)}").to_pandas()
# Fetch all rows
rows = result.fetchall()
return [ScoredResult(
id = result["id"],
payload = result["payload"],
score = 0,
) for result in results.to_dict("index").values()]
return [
ScoredResult(
id=row["id"],
payload=row["payload"],
score=0
)
for row in rows
]
except Exception as e:
print(f"Error retrieving data: {e}")
return []
async def search(
self,
collection_name: str,
query_text: str = None,
query_vector: List[float] = None,
query_text: Optional[str] = None,
query_vector: Optional[List[float]] = None,
limit: int = 5,
with_vector: bool = False,
):
) -> List[ScoredResult]:
# Validate inputs
if query_text is None and query_vector is None:
raise ValueError("One of query_text or query_vector must be provided!")
# Get the vector for query_text if provided
if query_text and not query_vector:
query_vector = (await self.embedding_engine.embed_text([query_text]))[0]
async with self.engine.begin() as connection:
collection = await connection.open_table(collection_name)
# Use async session to connect to the database
async with self.get_async_session() as session:
try:
PGVectorDataPoint = Table(collection_name, Base.metadata, autoload_with=self.engine)
results = await collection.vector_search(query_vector).limit(limit).to_pandas()
closest_items = await session.execute(select(PGVectorDataPoint, PGVectorDataPoint.c.vector.cosine_distance(query_vector).label('similarity')).order_by(PGVectorDataPoint.c.vector.cosine_distance(query_vector)).limit(limit))
result_values = list(results.to_dict("index").values())
vector_list = []
# Extract distances and find min/max for normalization
for vector in closest_items:
#TODO: Add normalization of similarity score
vector_list.append(vector)
min_value = 100
max_value = 0
# Create and return ScoredResult objects
return [
ScoredResult(
id=str(row.id),
payload=row.payload,
score=row.similarity
)
for row in vector_list
]
for result in result_values:
value = float(result["_distance"])
if value > max_value:
max_value = value
if value < min_value:
min_value = value
normalized_values = [(result["_distance"] - min_value) / (max_value - min_value) for result in result_values]
return [ScoredResult(
id = str(result["id"]),
payload = result["payload"],
score = normalized_values[value_index],
) for value_index, result in enumerate(result_values)]
except Exception as e:
print(f"Error during search: {e}")
return []
async def batch_search(
self,
@ -152,23 +195,11 @@ class PGVectorAdapter(SQLAlchemyAdapter, VectorDBInterface):
limit: int = None,
with_vectors: bool = False,
):
query_vectors = await self.embedding_engine.embed_text(query_texts)
return asyncio.gather(
*[self.search(
collection_name = collection_name,
query_vector = query_vector,
limit = limit,
with_vector = with_vectors,
) for query_vector in query_vectors]
)
pass
async def delete_data_points(self, collection_name: str, data_point_ids: list[str]):
async with self.engine.begin() as connection:
collection = await connection.open_table(collection_name)
results = await collection.delete(f"id IN {tuple(data_point_ids)}")
return results
pass
async def prune(self):
# Clean up the database if it was set up as temporary
self.delete_database()
await self.delete_database()