view libervia/backend/tools/common/async_utils.py @ 4306:94e0968987cd

plugin XEP-0033: code modernisation, improve delivery, data validation: - Code has been rewritten using Pydantic models and `async` coroutines for data validation and cleaner element parsing/generation. - Delivery has been completely rewritten. It now works even if server doesn't support multicast, and send to local multicast service first. Delivering to local multicast service first is due to bad support of XEP-0033 in server (notably Prosody which has an incomplete implementation), and the current impossibility to detect if a sub-domain service handles fully multicast or only for local domains. This is a workaround to have a good balance between backward compatilibity and use of bandwith, and to make it work with the incoming email gateway implementation (the gateway will only deliver to entities of its own domain). - disco feature checking now uses `async` corountines. `host` implementation still use Deferred return values for compatibility with legacy code. rel 450
author Goffi <goffi@goffi.org>
date Thu, 26 Sep 2024 16:12:01 +0200 (4 months ago)
parents 0d7bb4df2343
children
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#!/usr/bin/env python3


# Libervia: an XMPP client
# Copyright (C) 2009-2021 Jérôme Poisson (goffi@goffi.org)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero 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 Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

"""tools to launch process in a async way (using Twisted)"""

from collections import OrderedDict
from typing import Optional, Callable, Awaitable
from libervia.backend.core.log import getLogger


log = getLogger(__name__)


def async_lru(maxsize: Optional[int] = 50) -> Callable:
    """Decorator to cache async function results using LRU algorithm

    @param maxsize: maximum number of items to keep in cache.
        None to have no limit

    """

    def decorator(func: Callable) -> Callable:
        cache = OrderedDict()

        async def wrapper(*args) -> Awaitable:
            if args in cache:
                log.debug(f"using result in cache for {args}")
                cache.move_to_end(args)
                result = cache[args]
                return result
            log.debug(f"caching result for {args}")
            result = await func(*args)
            cache[args] = result
            if maxsize is not None and len(cache) > maxsize:
                value = cache.popitem(False)
                log.debug(f"Removing LRU value: {value}")
            return result

        return wrapper

    return decorator