litecord/litecord/pubsub/guild.py

122 lines
4.0 KiB
Python

"""
Litecord
Copyright (C) 2018-2021 Luna Mendes and Litecord Contributors
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, version 3 of the License.
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/>.
"""
from typing import List, Tuple
from quart import current_app as app
from logbook import Logger
from .dispatcher import DispatcherWithState, GatewayEvent
from litecord.gateway.state import GatewayState
from litecord.enums import EVENTS_TO_INTENTS
from litecord.permissions import get_permissions
log = Logger(__name__)
def can_dispatch(event_type, event_data, state) -> bool:
# If we're sending to the same user for this kind of event,
# bypass event logic (always send)
if event_type == "GUILD_MEMBER_UPDATE":
user_id = int(event_data["user"]["id"])
return user_id == state.user_id
# TODO Guild Create and Req Guild Members have specific
# logic regarding the presence intent.
wanted_intent = EVENTS_TO_INTENTS.get(event_type)
if wanted_intent is not None:
state_has_intent = (state.intents & wanted_intent) == wanted_intent
return state_has_intent
class GuildDispatcher(DispatcherWithState[int, str, GatewayEvent, List[str]]):
"""Guild backend for Pub/Sub."""
async def sub_user(
self, guild_id: int, user_id: int
) -> Tuple[List[GatewayState], List[int]]:
states = app.state_manager.fetch_states(user_id, guild_id)
for state in states:
await self.sub(guild_id, state.session_id)
# instead of calculating which channels to subscribe to
# inside guild dispatcher, we calculate them in here, so that
# we remove complexity of the dispatcher.
guild_chan_ids = await app.storage.get_channel_ids(guild_id)
channel_ids = []
for channel_id in guild_chan_ids:
perms = await get_permissions(user_id, channel_id)
if perms.bits.read_messages:
channel_ids.append(channel_id)
return states, channel_ids
async def unsub_user(
self, guild_id: int, user_id: int
) -> Tuple[List[GatewayState], List[int]]:
states = app.state_manager.fetch_states(user_id, guild_id)
for state in states:
await self.unsub(guild_id, state.session_id)
guild_chan_ids = await app.storage.get_channel_ids(guild_id)
return states, guild_chan_ids
async def dispatch_filter(
self, guild_id: int, filter_function, event: GatewayEvent
):
session_ids = self.state[guild_id]
sessions: List[str] = []
event_type, event_data = event
for session_id in set(session_ids):
if not filter_function(session_id):
continue
try:
state = app.state_manager.fetch_raw(session_id)
except KeyError:
await self.unsub(guild_id, session_id)
continue
if not state:
await self.unsub(guild_id, session_id)
continue
if not can_dispatch(event_type, event_data, state):
continue
try:
await state.dispatch(*event)
except Exception:
log.exception("error while dispatching to {}", state.session_id)
continue
sessions.append(session_id)
log.info("Dispatched {} {!r} to {} states", guild_id, event[0], len(sessions))
return sessions
async def dispatch(self, guild_id: int, event):
"""Dispatch an event to all subscribers of the guild."""
return await self.dispatch_filter(guild_id, lambda sess_id: True, event)