airflow/models/base.py

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from typing import Any

from sqlalchemy import MetaData
from sqlalchemy.ext.declarative import declarative_base

from airflow.configuration import conf

SQL_ALCHEMY_SCHEMA = conf.get("core", "SQL_ALCHEMY_SCHEMA")

metadata = (
    None if not SQL_ALCHEMY_SCHEMA or SQL_ALCHEMY_SCHEMA.isspace() else MetaData(schema=SQL_ALCHEMY_SCHEMA)
)
Base = declarative_base(metadata=metadata)  # type: Any

ID_LEN = 250


# used for typing
class Operator:
    """Class just used for Typing"""


def get_id_collation_args():
    """Get SQLAlchemy args to use for COLLATION"""
    collation = conf.get('core', 'sql_engine_collation_for_ids', fallback=None)
    if collation:
        return {'collation': collation}
    else:
        return {}


COLLATION_ARGS = get_id_collation_args()