python3.8使用nacos 加入watcher 后报错

来源：29-6 service层集成nacos

qq_慕的地1326115

2022-07-12

图片描述
不加watcher 是正常的

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3回答

石小咚丶

2023-03-08

参考 [同学的建议]https://coding.imooc.com/learn/questiondetail/Dg8m5YZLkja6Wa4B.html , 我觉得可以尝试使用重载的方式解决这个问题，Python 3.9

import json
import platform
from multiprocessing import Process
from threading import Thread

import nacos
from loguru import logger
from nacos import NacosException
from nacos.params import group_key
from nacos.commons import synchronized_with_attr
from nacos.client import process_common_config_params, WatcherWrap


class NacosClient(nacos.NacosClient):
    """"""

    @synchronized_with_attr("pulling_lock")
    def add_config_watchers(self, data_id, group, cb_list, content=None):
        if not cb_list:
            raise NacosException("A callback function is needed.")
        data_id, group = process_common_config_params(data_id, group)
        logger.info("[add-watcher] data_id:%s, group:%s, namespace:%s" % (data_id, group, self.namespace))
        cache_key = group_key(data_id, group, self.namespace)
        wl = self.watcher_mapping.get(cache_key)
        if not wl:
            wl = list()
            self.watcher_mapping[cache_key] = wl
        if not content:
            content = self.get_config(data_id, group)
        last_md5 = NacosClient.get_md5(content)
        for cb in cb_list:
            wl.append(WatcherWrap(cache_key, cb, last_md5))
            logger.info("[add-watcher] watcher has been added for key:%s, new callback is:%s, callback number is:%s" % (
                cache_key, cb.__name__, len(wl)))

        if self.puller_mapping is None:
            logger.debug("[add-watcher] pulling should be initialized")
            self._init_pulling()

        if cache_key in self.puller_mapping:
            logger.debug("[add-watcher] key:%s is already in pulling" % cache_key)
            return

        for key, puller_info in self.puller_mapping.items():
            if len(puller_info[1]) < self.pulling_config_size:
                logger.debug("[add-watcher] puller:%s is available, add key:%s" % (puller_info[0], cache_key))
                puller_info[1].append(cache_key)
                self.puller_mapping[cache_key] = puller_info
                break
        else:
            logger.debug("[add-watcher] no puller available, new one and add key:%s" % cache_key)
            key_list = self.process_mgr.list()
            key_list.append(cache_key)
            sys_os = platform.system()
            if sys_os == 'Windows' or sys_os == "Darwin":
                puller = Thread(target=self._do_pulling, args=(key_list, self.notify_queue))
                puller.setDaemon(True)
            else:
                puller = Process(target=self._do_pulling, args=(key_list, self.notify_queue))
                puller.daemon = True
            puller.start()
            self.puller_mapping[cache_key] = (puller, key_list)

使用重载的方式在以后更换环境或者服务上线的时候会更加方便一些

addr = ""
group = ""
data_id = ""
namespace = ""

def dispose():
    pass

client = NacosClient(addr, namespace=namespace, username="nacos", password="nacos")

if __name__ == "__main__":
    client.add_config_watcher(data_id, group, dispose)