from sqlalchemy import Column, String, TIMESTAMP


class TimestampMixin:
    created_at = Column(TIMESTAMP, server_default="CURRENT_TIMESTAMP")
    modified_at = Column(
        TIMESTAMP, server_default="CURRENT_TIMESTAMP", onupdate="CURRENT_TIMESTAMP"
    )
    created_by = Column(String(255), nullable=False)
    modified_by = Column(String(255), nullable=True)