sqlalchemy orm repr

base.py

# TODO: fix high memory usage for rich models


class Base:
    @classmethod
    def get_real_column_name(cls, attr_name: str) -> str:
        return getattr(inspect(cls).c, attr_name).name

    def __str__(self) -> str:
        return self.__repr__()

    def __repr__(self) -> str:
        """
        General __repr__ implementation for sqlalchemy ORM models to show columns and relationships.
        To ignore specific fields overload method _excluded_attributes().

        https://stackoverflow.com/questions/21206818/sqlalchemy-get-relationships-from-a-db-model
        """
        attrs = []
        for attr in inspect(self).attrs:
            if attr.key in self._excluded_attributes():
                continue
            value = self._repr_attribute(attr.loaded_value)
            attrs.append(f"{attr.key}={value}")

        attrs.reverse()
        values_str = ", ".join(attrs)
        cls_name = self.__class__.__name__
        return f"<{cls_name}({values_str})>"

    def _excluded_attributes(self) -> set[str]:
        return set()

    @staticmethod
    def _repr_attribute(value: Any) -> str:
        if isinstance(value, str) and len(value) > MAX_STR_COLUMN_REPR_LEN:
            value = value[:MAX_STR_COLUMN_REPR_LEN] + "..."
        elif isinstance(value, sqlalchemy.util.langhelpers._symbol):
            value = "<not loaded>"
        else:
            value = repr(value)
        return value