step 2 with basic crud implemented

app/db.py

@@ -1,6 +1,7 @@
 from typing import Generator
 
-from sqlalchemy import create_engine
+from sqlalchemy import create_engine, event
+from sqlalchemy.engine import make_url
 from sqlalchemy.orm import DeclarativeBase, Session, sessionmaker
 
 from app.config import get_settings
@@ -14,8 +15,31 @@ class Base(DeclarativeBase):
 
 
 def _build_engine(database_url: str):
+    _ensure_sqlite_directory(database_url)
     connect_args = {"check_same_thread": False} if database_url.startswith("sqlite") else {}
-    return create_engine(database_url, connect_args=connect_args)
+    created_engine = create_engine(database_url, connect_args=connect_args)
+
+    if database_url.startswith("sqlite"):
+        @event.listens_for(created_engine, "connect")
+        def set_sqlite_pragma(dbapi_connection, connection_record):
+            cursor = dbapi_connection.cursor()
+            cursor.execute("PRAGMA foreign_keys=ON")
+            cursor.close()
+
+    return created_engine
+
+
+def _ensure_sqlite_directory(database_url: str) -> None:
+    if not database_url.startswith("sqlite"):
+        return
+
+    database_path = make_url(database_url).database
+    if not database_path or database_path == ":memory:":
+        return
+
+    from pathlib import Path
+
+    Path(database_path).parent.mkdir(parents=True, exist_ok=True)
 
 
 def configure_database(database_url: str | None = None) -> None:
@@ -23,6 +47,8 @@ def configure_database(database_url: str | None = None) -> None:
 
     settings = get_settings()
     resolved_database_url = database_url or settings.database_url
+    if engine is not None:
+        engine.dispose()
     engine = _build_engine(resolved_database_url)
     SessionLocal.configure(bind=engine)