Files
nvi/api/tools/db.py

40 lines
1.2 KiB
Python

"""SQLAlchemy engine for the warehouse.
Per-connection defaults (search_path, statement_timeout) are baked into the
engine via libpq's `options` connect_arg so we never SET them at the SQL
layer. Read-only mode for query execution is requested via SQLAlchemy's
`execution_options(postgresql_readonly=True)`.
"""
from __future__ import annotations
from functools import lru_cache
from sqlalchemy import create_engine
from sqlalchemy.engine import Engine
from api.config import get_settings
SCHEMA = "financial"
DEFAULT_STATEMENT_TIMEOUT_MS = 10_000
@lru_cache(maxsize=1)
def get_engine() -> Engine:
url = get_settings().database_url
if url.startswith("postgresql://"):
url = url.replace("postgresql://", "postgresql+psycopg://", 1)
return create_engine(
url,
pool_pre_ping=True,
future=True,
# libpq -c options run before any SQL the app issues — no need to
# SET search_path / statement_timeout at execution time.
connect_args={
"options": (
f"-c search_path={SCHEMA},public "
f"-c statement_timeout={DEFAULT_STATEMENT_TIMEOUT_MS}"
),
},
)