
# Copyright 2018-2019 The Wazo Authors  (see the AUTHORS file)
# SPDX-License-Identifier: GPL-3.0-or-later

import os
from alembic import context
from sqlalchemy import create_engine
from sqlalchemy.pool import NullPool
from logging.config import fileConfig

# 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.get_main_option('configure_logging', 'true') == 'true':
    fileConfig(config.config_file_name)

# other values from the config, defined by the needs of env.py,
# can be acquired:
# my_important_option = config.get_main_option("my_important_option")
# ... etc.

URI = os.getenv('ALEMBIC_DB_URI', None)


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 = URI or config.get_main_option("sqlalchemy.url")
    context.configure(url=url)

    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.

    """
    url = URI or config.get_main_option("sqlalchemy.url")
    engine = create_engine(url, poolclass=NullPool)

    connection = engine.connect()
    context.configure(connection=connection)

    try:
        with context.begin_transaction():
            context.run_migrations()
    finally:
        connection.close()


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