Initial commit

app/db.py

@@ -0,0 +1,58 @@
+from __future__ import annotations
+
+from contextlib import contextmanager
+from pathlib import Path
+from typing import Iterator
+
+from sqlalchemy import create_engine, text
+from sqlalchemy.orm import DeclarativeBase, Session, sessionmaker
+
+from app.config import get_settings
+
+
+class Base(DeclarativeBase):
+    pass
+
+
+def _engine_url() -> str:
+    url = get_settings().app.database_url
+    if url.startswith("sqlite:///") and not url.startswith("sqlite:////"):
+        db_path = url.removeprefix("sqlite:///")
+        if db_path and db_path != ":memory:":
+            Path(db_path).parent.mkdir(parents=True, exist_ok=True)
+    return url
+
+
+engine = create_engine(_engine_url(), future=True, pool_pre_ping=True)
+SessionLocal = sessionmaker(bind=engine, autoflush=False, autocommit=False, future=True)
+
+
+def init_db() -> None:
+    from app import models  # noqa: F401
+
+    Base.metadata.create_all(bind=engine)
+
+
+def get_db() -> Iterator[Session]:
+    with SessionLocal() as session:
+        yield session
+
+
+@contextmanager
+def session_scope() -> Iterator[Session]:
+    with SessionLocal() as session:
+        try:
+            yield session
+            session.commit()
+        except Exception:
+            session.rollback()
+            raise
+
+
+def database_ok() -> bool:
+    try:
+        with engine.connect() as conn:
+            conn.execute(text("select 1"))
+        return True
+    except Exception:
+        return False