Source code for airflow.models.base

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from typing import Any

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

from airflow.configuration import conf

[docs]SQL_ALCHEMY_SCHEMA = conf.get("database", "SQL_ALCHEMY_SCHEMA")
[docs]metadata = ( None if not SQL_ALCHEMY_SCHEMA or SQL_ALCHEMY_SCHEMA.isspace() else MetaData(schema=SQL_ALCHEMY_SCHEMA)
[docs]Base: Any = declarative_base(metadata=metadata)
[docs]ID_LEN = 250
[docs]def get_id_collation_args(): """Get SQLAlchemy args to use for COLLATION""" collation = conf.get('database', 'sql_engine_collation_for_ids', fallback=None) if collation: return {'collation': collation} else: # Automatically use utf8mb3_bin collation for mysql # This is backwards-compatible. All our IDS are ASCII anyway so even if # we migrate from previously installed database with different collation and we end up mixture of # COLLATIONS, it's not a problem whatsoever (and we keep it small enough so that our indexes # for MYSQL will not exceed the maximum index size. # # See # # We cannot use session/dialect as at this point we are trying to determine the right connection # parameters, so we use the connection conn = conf.get('database', 'sql_alchemy_conn', fallback='') if conn.startswith('mysql') or conn.startswith("mariadb"): return {'collation': 'utf8mb3_bin'} return {}
[docs]COLLATION_ARGS = get_id_collation_args()
[docs]def StringID(*, length=ID_LEN, **kwargs) -> String: return String(length=length, **kwargs, **COLLATION_ARGS)

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