Source code for pcapkit.protocols.application.ftp_data

# -*- coding: utf-8 -*-
"""FTP_DATA - FTP Data Channel
=================================

.. module:: pcapkit.protocols.application.ftp_data

:mod:`pcapkit.protocols.application.ftp_data` contains
:class:`~pcapkit.protocols.application.ftp_data.FTP_DATA` only,
which implements an extractor for the data channel of File
Transfer Protocol (FTP) [*]_, whose octets it keeps undissected.

.. [*] https://en.wikipedia.org/wiki/File_Transfer_Protocol

.. versionadded:: 1.5.0

   Moved here from :mod:`pcapkit.protocols.application.ftp`, which keeps
   :class:`~pcapkit.protocols.application.ftp.FTP` alone. The control and data
   channels are dispatched separately -- FTP at TCP port 21, the data channel
   at port 20 -- so each is a protocol of its own and gets its own module,
   unlike :class:`~pcapkit.protocols.application.rarp.RARP` and
   :class:`~pcapkit.protocols.application.rarp.DRARP`, which one dispatch
   entry reaches (:issue:`2285`).

"""
from typing import TYPE_CHECKING

from pcapkit.protocols.application.application import Application
from pcapkit.protocols.misc.raw import Raw

if TYPE_CHECKING:
    from typing_extensions import Literal

__all__ = ['FTP_DATA']




class FTP_DATA(Application, Raw):  # pylint: disable=abstract-method
    """This class implements FTP data channel transmission.

    The layer base :class:`~pcapkit.protocols.application.application.Application`
    comes first, for ``layer == 'Application'``, then the parsing base
    :class:`~pcapkit.protocols.misc.raw.Raw`, which keeps the channel's octets
    undissected. See :doc:`/contributing/conventions/protocol-layer-placement`.

    .. versionchanged:: 1.5.0

       Derives from :class:`~pcapkit.protocols.application.application.Application`
       as well as :class:`~pcapkit.protocols.misc.raw.Raw`, so its layer is
       ``'Application'``, where it was :obj:`None`, and its ``__index__`` is
       :meth:`Application.__index__
       <pcapkit.protocols.application.application.Application.__index__>`,
       raising :exc:`~pcapkit.utilities.exceptions.IntError` where it raised
       :exc:`~pcapkit.utilities.exceptions.UnsupportedCall` (:issue:`2285`).

    """

    ##########################################################################
    # Properties.
    ##########################################################################

    # name of current protocol
    @property
    def name(self) -> 'Literal["FTP_DATA"]':  # type: ignore[override]
        """Name of current protocol."""
        return 'FTP_DATA'