Source code for forml.provider.sink.null

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"""
Null writer sink implementation.
"""
import typing

from forml import io

if typing.TYPE_CHECKING:
    from forml.io import layout


[docs]class Sink(io.Sink, alias='null'):
    """Null sink with no real write action.

    It still returns the :class:`layout.Outcome <forml.io.layout.Outcome>` combo of schema and
    the payload.

    The provider can be enabled using the following :ref:`platform configuration <platform-config>`:

    .. code-block:: toml
       :caption: config.toml

        [SINK.blackhole]
        provider = "null"
    """

    class Writer(io.Sink.Writer):
        """Overridden writer."""

        @classmethod
        def write(cls, data: 'layout.Native', **kwargs: typing.Any) -> None:
            """Write is no-op."""
            return None