packable

packable(cls)

Decorator to convert a regular class into a PackableSample.

This decorator transforms a class into a dataclass that inherits from PackableSample, enabling automatic msgpack serialization/deserialization with special handling for NDArray fields.

The resulting class satisfies the Packable protocol, making it compatible with all atdata APIs that accept packable types (e.g., publish_schema, lens transformations, etc.).

Type Checking

The return type is annotated as type[PackableSample] so that IDEs and type checkers recognize the PackableSample methods (packed, as_wds, from_bytes, etc.). The @dataclass_transform() decorator ensures that field access from the original class is also preserved for type checking.

Parameters

Name	Type	Description	Default
cls	type[_T]	The class to convert. Should have type annotations for its fields.	required

Returns

Name	Type	Description
	type[PackableSample]	A new dataclass that inherits from PackableSample with the same
	type[PackableSample]	name and annotations as the original class. The class satisfies the
	type[PackableSample]	Packable protocol and can be used with Type[Packable] signatures.

Examples

>>> @packable
... class MyData:
...     name: str
...     values: NDArray
...
>>> sample = MyData(name="test", values=np.array([1, 2, 3]))
>>> bytes_data = sample.packed
>>> restored = MyData.from_bytes(bytes_data)
>>>
>>> # Works with Packable-typed APIs
>>> index.publish_schema(MyData, version="1.0.0")  # Type-safe