from sqlalchemy.ext.asyncio import async_sessionmaker, create_async_engine

from .settings import settings


def make_engine(**overrides):
    """A fresh async engine. Services that need more than one pool profile
    (see ledger/chaos.py for pool_starvation) call this more than once."""
    kwargs = dict(pool_pre_ping=True)
    kwargs.update(overrides)
    return create_async_engine(settings.postgres_dsn, **kwargs)


engine = make_engine(pool_size=20, max_overflow=10)
Session = async_sessionmaker(engine, expire_on_commit=False)