Initial commit

backend/migrations/env.py

@@ -0,0 +1,57 @@
+"""Alembic environment — runs raw SQL migrations against SQLite or Postgres.
+
+No SQLAlchemy ORM is used. Migrations are plain SQL scripts so the migration
+layer stays independent of any Python model objects.
+"""
+
+from __future__ import annotations
+
+import asyncio
+from logging.config import fileConfig
+from typing import Any
+
+from alembic import context
+
+# Load the alembic.ini logging config.
+if context.config.config_file_name is not None:
+    fileConfig(context.config.config_file_name)
+
+
+def run_migrations_offline() -> None:
+    """Emit SQL to stdout (used by `alembic upgrade --sql`)."""
+    url = context.config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url,
+        target_metadata=None,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def do_run_migrations(connection: Any) -> None:
+    context.configure(connection=connection, target_metadata=None)
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+async def run_migrations_online() -> None:
+    """Run migrations against a live DB connection."""
+    from sqlalchemy.ext.asyncio import create_async_engine
+
+    url = context.config.get_main_option("sqlalchemy.url")
+    # Coerce sqlite:// → sqlite+aiosqlite:// for async support.
+    if url and url.startswith("sqlite:///"):
+        url = url.replace("sqlite:///", "sqlite+aiosqlite:///", 1)
+
+    connectable = create_async_engine(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())