Remove unused resolver module

nbxmpp/resolver.py

-# Copyright (C) 2020 Philipp Hörist <philipp AT hoerist.com>
-#
-# This file is part of nbxmpp.
-#
-# This program is free software; you can redistribute it and/or
-# modify it under the terms of the GNU 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 General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program; If not, see <http://www.gnu.org/licenses/>.
-
-import logging
-
-from gi.repository import Gio
-from gi.repository import GLib
-
-
-log = logging.getLogger('nbxmpp.resolver')
-
-
-class DNSResolveRequest:
-    def __init__(self, cache, domain, callback):
-        self._domain = domain
-        self._result = self._lookup_cache(cache)
-        self._callback = callback
-
-    @property
-    def result(self):
-        return self._result
-
-    @result.setter
-    def result(self, value):
-        self._result = value
-
-    @property
-    def is_cached(self):
-        return self.result is not None
-
-    def _lookup_cache(self, cache):
-        cached_request = cache.get(self)
-        if cached_request is None:
-            return None
-        return cached_request.result
-
-    def finalize(self):
-        GLib.idle_add(self._callback, self.result)
-        self._callback = None
-
-    def __hash__(self):
-        raise NotImplementedError
-
-    def __eq__(self, other):
-        return hash(other) == hash(self)
-
-
-class AlternativeMethods(DNSResolveRequest):
-    def __init__(self, *args, **kwargs):
-        DNSResolveRequest.__init__(self, *args, **kwargs)
-
-    @property
-    def hostname(self):
-        return '_xmppconnect.%s' % self._domain
-
-    def __hash__(self):
-        return hash(self.hostname)
-
-
-class Singleton(type):
-    _instances = {}
-    def __call__(cls, *args, **kwargs):
-        if cls not in cls._instances:
-            cls._instances[cls] = super(Singleton, cls).__call__(*args,
-                                                                 **kwargs)
-        return cls._instances[cls]
-
-
-class GioResolver(metaclass=Singleton):
-    def __init__(self):
-        self._cache = {}
-
-    def _cache_request(self, request):
-        self._cache[request] = request
-
-    def resolve_alternatives(self, domain, callback):
-        request = AlternativeMethods(self._cache, domain, callback)
-        if request.is_cached:
-            request.finalize()
-            return
-
-        Gio.Resolver.get_default().lookup_records_async(
-            request.hostname,
-            Gio.ResolverRecordType.TXT,
-            None,
-            self._on_alternatives_result,
-            request)
-
-    def _on_alternatives_result(self, resolver, result, request):
-        try:
-            results = resolver.lookup_records_finish(result)
-        except GLib.Error as error:
-            log.info(error)
-            request.finalize()
-            return
-
-        try:
-            websocket_uri = self._parse_alternative_methods(results)
-        except Exception:
-            log.exception('Failed to parse alternative '
-                          'connection methods: %s', results)
-            request.finalize()
-            return
-
-        request.result = websocket_uri
-        self._cache_request(request)
-        request.finalize()
-
-    @staticmethod
-    def _parse_alternative_methods(variant_results):
-        result_list = [res[0][0] for res in variant_results]
-        for result in result_list:
-            if result.startswith('_xmpp-client-websocket'):
-                return result.split('=')[1]
-        return None
-
-
-if __name__ == '__main__':
-    import sys
-
-    try:
-        domain_ = sys.argv[1]
-    except Exception:
-        print('Provide domain name as argument')
-        sys.exit()
-
-    # Execute:
-    # > python3 -m nbxmpp.resolver domain
-
-    def on_result(result):
-        print('Result: ', result)
-        mainloop.quit()
-
-    GioResolver().resolve_alternatives(domain_, on_result)
-    mainloop = GLib.MainLoop()
-    mainloop.run()