refactor: integrate model platform backend

migrations/env.py

@@ -0,0 +1,127 @@
+from __future__ import annotations
+
+import asyncio
+import os
+from decimal import Decimal, InvalidOperation
+from logging.config import fileConfig
+from typing import Any
+
+from alembic import context
+from sqlalchemy import Connection, pool
+from sqlalchemy.ext.asyncio import async_engine_from_config
+
+from common.db import Base
+
+config = context.config
+
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+target_metadata = Base.metadata
+
+
+def canonical_default(value: Any) -> tuple[str, Any] | None:
+    """Normalize harmless MySQL quoting and numeric formatting differences."""
+    if value is None:
+        return None
+
+    text_value = str(value).strip()
+    while (
+        len(text_value) >= 2
+        and text_value.startswith("(")
+        and text_value.endswith(")")
+    ):
+        text_value = text_value[1:-1].strip()
+    if (
+        len(text_value) >= 2
+        and text_value[0] == text_value[-1]
+        and text_value[0] in {"'", '"'}
+    ):
+        text_value = text_value[1:-1]
+
+    try:
+        return ("number", Decimal(text_value).normalize())
+    except InvalidOperation:
+        return ("text", text_value.casefold())
+
+
+def compare_server_default(
+    migration_context: Any,
+    inspected_column: Any,
+    metadata_column: Any,
+    inspected_default: str | None,
+    metadata_default: Any,
+    rendered_metadata_default: str | None,
+) -> bool | None:
+    """Suppress formatting-only differences and defer real changes to Alembic."""
+    del migration_context, inspected_column, metadata_column, metadata_default
+    if canonical_default(inspected_default) == canonical_default(
+        rendered_metadata_default
+    ):
+        return False
+    return None
+
+
+def database_url() -> str:
+    """Return the runtime database URL without storing credentials in the repo."""
+    try:
+        return os.environ["DATABASE_URL"]
+    except KeyError as exc:
+        raise RuntimeError(
+            "DATABASE_URL is required for Alembic commands"
+        ) from exc
+
+
+def configure_context(*, connection: Connection | None = None) -> None:
+    options = {
+        "target_metadata": target_metadata,
+        "compare_type": True,
+        "compare_server_default": compare_server_default,
+    }
+    if connection is None:
+        context.configure(
+            url=database_url(),
+            literal_binds=True,
+            dialect_opts={"paramstyle": "named"},
+            **options,
+        )
+    else:
+        context.configure(connection=connection, **options)
+
+
+def run_migrations_offline() -> None:
+    configure_context()
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def do_run_migrations(connection: Connection) -> None:
+    configure_context(connection=connection)
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+async def run_async_migrations() -> None:
+    section = config.get_section(config.config_ini_section, {})
+    section["sqlalchemy.url"] = database_url()
+    connectable = async_engine_from_config(
+        section,
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+
+    try:
+        async with connectable.connect() as connection:
+            await connection.run_sync(do_run_migrations)
+    finally:
+        await connectable.dispose()
+
+
+def run_migrations_online() -> None:
+    asyncio.run(run_async_migrations())
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()