outsource()

outsource() can be used to declare that a value should be stored in an external object when you create it. This is useful in cases where you already know that a value can only be stored externally, and you want to return it from a function, for example.

from inline_snapshot import outsource, register_format_alias, snapshot

register_format_alias(".png", ".bin")


def check_captcha(input_data):
    # Perform operations on input_data ...
    the_data = b"image data ..."

    return {
        "size": "200x100",
        "difficulty": 8,
        "picture": outsource(the_data, suffix=".png"),
    }


def test_captcha():
    assert check_captcha("abc") == snapshot()

inline-snapshot always generates an external object in this case.

from inline_snapshot import outsource, register_format_alias, snapshot

from inline_snapshot import external

register_format_alias(".png", ".bin")


def check_captcha(input_data):
    # Perform operations on input_data ...
    the_data = b"image data ..."

    return {
        "size": "200x100",
        "difficulty": 8,
        "picture": outsource(the_data, suffix=".png"),
    }


def test_captcha():
    assert check_captcha("abc") == snapshot(
        {
            "size": "200x100",
            "difficulty": 8,
            "picture": external("hash:0da2cc316111*.png"),
        }
    )

outsource() was the only way to create external objects until inline-snapshot 0.24. External objects can now also be created with external() and used like snapshot().

Info

It is not possible to specify the storage protocol when you call outsource() because this is something that should be under the control of the user who uses this external object.

Limitation

outsource() currently always uses the hash protocol when it creates a new external object. This is a limitation that will be addressed in the future. It is possible to change it later to external("uuid:") manually if you want to store it in a different location.