migrations/env.py

import os
from logging.config import fileConfig

from alembic import context
from sqlalchemy import engine_from_config
from sqlalchemy import pool

import os
import sys

# Get the absolute path to the project root directory
project_root = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))

# Add the project root directory to the Python path
sys.path.insert(0, project_root)

config = context.config

fileConfig(config.config_file_name)

from core.db import Base

target_metadata = Base.metadata


def get_url():
    from core import settings
    return settings.POSTGRES_DATABASE_URI


def run_migrations_offline():
    """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 = get_url()
    context.configure(
        url=url,
        target_metadata=target_metadata,
        literal_binds=True,
        dialect_opts={"paramstyle": "named"},
    )

    with context.begin_transaction():
        context.run_migrations()


def run_migrations_online():
    """Run migrations in 'online' mode.

    In this scenario we need to create an Engine
    and associate a connection with the context.

    """
    config_data = config.get_section(config.config_ini_section)
    config_data["sqlalchemy.url"] = get_url()

    connectable = engine_from_config(
        config_data,
        prefix="sqlalchemy.",
        poolclass=pool.NullPool,
    )

    with connectable.connect() as connection:
        context.configure(
            connection=connection, target_metadata=target_metadata
        )

        with context.begin_transaction():
            context.run_migrations()


if context.is_offline_mode():
    run_migrations_offline()
else:
    run_migrations_online()