Class Struct

sdk/python/feast/types.py:263–307

A Struct represents a structured type with named, typed fields. Attributes: fields: A dictionary mapping field names to their FeastTypes.

class Struct(ComplexFeastType):
    """
    A Struct represents a structured type with named, typed fields.

    Attributes:
        fields: A dictionary mapping field names to their FeastTypes.
    """

    fields: Dict[str, Union[PrimitiveFeastType, "ComplexFeastType"]]

    def __init__(
        self, fields: Dict[str, Union[PrimitiveFeastType, "ComplexFeastType"]]
    ):
        if not fields:
            raise ValueError("Struct must have at least one field.")
        self.fields = fields

    def to_value_type(self) -> ValueType:
        return ValueType.STRUCT

    def to_pyarrow_type(self) -> pyarrow.DataType:
        pa_fields = []
        for name, feast_type in self.fields.items():
            pa_type = from_feast_to_pyarrow_type(feast_type)
            pa_fields.append(pyarrow.field(name, pa_type))
        return pyarrow.struct(pa_fields)

    def __str__(self):
        field_strs = ", ".join(
            f"{name}: {ftype}" for name, ftype in self.fields.items()
        )
        return f"Struct({{{field_strs}}})"

    def __eq__(self, other):
        if isinstance(other, Struct):
            return self.fields == other.fields
        return False

    def __hash__(self):
        return hash(
            (
                "Struct",
                tuple((k, hash(v)) for k, v in sorted(self.fields.items())),
            )
        )


FeastType = Union[ComplexFeastType, PrimitiveFeastType]