Alembic experiments

alembic/env.py

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+"""Alembic environment configuration for async SQLAlchemy."""
+
+import asyncio
+from logging.config import fileConfig
+
+from alembic import context
+from sqlalchemy import pool
+from sqlalchemy.engine import Connection
+from sqlalchemy.ext.asyncio import async_engine_from_config
+
+# Import your models' Base to enable autogenerate
+from alpine_bits_python.config_loader import load_config
+from alpine_bits_python.db import (
+    Base,
+    configure_schema,
+    get_database_schema,
+    get_database_url,
+)
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+# Load application config to get database URL and schema
+try:
+    app_config = load_config()
+except (FileNotFoundError, KeyError, ValueError):
+    # Fallback if config can't be loaded (e.g., during initial setup)
+    app_config = {}
+
+# Get database URL from application config
+db_url = get_database_url(app_config)
+if db_url:
+    config.set_main_option("sqlalchemy.url", db_url)
+
+# Get schema name from application config
+schema_name = get_database_schema(app_config)
+if schema_name:
+    # Configure schema for all tables before migrations
+    configure_schema(schema_name)
+
+# add your model's MetaData object here for 'autogenerate' support
+target_metadata = Base.metadata
+
+
+def run_migrations_offline() -> None:
+    """Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+    """
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+        version_table_schema=schema_name,  # Store alembic_version in our schema
+        include_schemas=True,
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def do_run_migrations(connection: Connection) -> None:
+    """Run migrations with the given connection."""
+    context.configure(
+        connection=connection,
+        target_metadata=target_metadata,
+        version_table_schema=schema_name,  # Store alembic_version in our schema
+        include_schemas=True,  # Allow Alembic to work with non-default schemas
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+async def run_async_migrations() -> None:
+    """Run migrations in 'online' mode using async engine.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+    """
+    # Get the config section for sqlalchemy settings
+    configuration = config.get_section(config.config_ini_section, {})
+
+    # Add connect_args for PostgreSQL schema support if needed
+    if schema_name and "postgresql" in configuration.get("sqlalchemy.url", ""):
+        configuration["connect_args"] = {
+            "server_settings": {"search_path": f"{schema_name},public"}
+        }
+
+    # Create async engine
+    connectable = async_engine_from_config(
+        configuration,
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+
+    async with connectable.connect() as connection:
+        await connection.run_sync(do_run_migrations)
+
+    await connectable.dispose()
+
+
+def run_migrations_online() -> None:
+    """Run migrations in 'online' mode - entry point."""
+    asyncio.run(run_async_migrations())
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()