feat: create backend skeleton

backend/migrations/env.py

@@ -0,0 +1,50 @@
+import asyncio
+from logging.config import fileConfig
+
+from alembic import context
+from sqlalchemy.ext.asyncio import create_async_engine
+from sqlmodel import SQLModel
+
+from utils.db import models  # noqa: F401
+from utils.env import env
+
+config = context.config
+
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+target_metadata = SQLModel.metadata
+
+
+def _async_url() -> str:
+    return env.db.connection_url.replace("postgresql://", "postgresql+asyncpg://", 1)
+
+
+def run_migrations_offline() -> None:
+    context.configure(
+        url=_async_url(),
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def _do_run_migrations(connection) -> None:  # noqa: ANN001
+    context.configure(connection=connection, target_metadata=target_metadata)
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+async def run_migrations_online() -> None:
+    connectable = create_async_engine(_async_url())
+    async with connectable.connect() as connection:
+        await connection.run_sync(_do_run_migrations)
+    await connectable.dispose()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    asyncio.run(run_migrations_online())