# Source code for aioxmpp.shim.service

    ########################################################################
    # File name: service.py
    # This file is part of: aioxmpp
    #
    # LICENSE
    #
    # This program is free software: you can redistribute it and/or modify
    # it under the terms of the GNU Lesser General Public License as
    # published by the Free Software Foundation, either version 3 of the
    # License, or (at your option) any later version.
    #
    # This program is distributed in the hope that it will be useful, but
    # WITHOUT ANY WARRANTY; without even the implied warranty of
    # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    # Lesser General Public License for more details.
    #
    # You should have received a copy of the GNU Lesser General Public
    # License along with this program.  If not, see
    # <http://www.gnu.org/licenses/>.
    #
    ########################################################################
    import asyncio

    import aioxmpp.service

    from aioxmpp.utils import namespaces

    class SHIMService(aioxmpp.service.Service):
        """
        This service implements :xep:`131` feature advertisement.

        It registers the ``http://jabber.org/protocol/shim`` node with the
        :class:`.DiscoServer`. It publishes the supported headers on that node as
        specified in the XEP.

        To announce supported headers, use the :meth:`register_header` and
        :meth:`unregister_header` methods.

        .. automethod:: register_header

        .. automethod:: unregister_header

        .. versionchanged:: 0.8

           This class was formerly known as :class:`aioxmpp.shim.Service`. It
           is still available under that name, but the alias will be removed in
           1.0.
        """

        ORDER_AFTER = [aioxmpp.DiscoServer]

        def __init__(self, client, **kwargs):
            super().__init__(client, **kwargs)

            self._disco = self.dependencies[aioxmpp.DiscoServer]
            self._disco.register_feature(namespaces.xep0131_shim)

            self._node = aioxmpp.disco.StaticNode()
            self._disco.mount_node(
                namespaces.xep0131_shim,
                self._node
            )

        async def _shutdown(self):
            self._disco.unregister_feature(namespaces.xep0131_shim)
            self._disco.unmount_node(namespaces.xep0131_shim)
            await super()._shutdown()

        def register_header(self, name):
            """
            Register support for the SHIM header with the given `name`.

            If the header has already been registered as supported,
            :class:`ValueError` is raised.
            """

            self._node.register_feature(
                "#".join([namespaces.xep0131_shim, name])
            )

        def unregister_header(self, name):
            """
            Unregister support for the SHIM header with the given `name`.

            If the header is currently not registered as supported,
            :class:`KeyError` is raised.
            """

            self._node.unregister_feature(
                "#".join([namespaces.xep0131_shim, name])
            )