我需要将更新事件传达给我的 python 脚本的所有运行实例,我希望代码尽可能简单。我对正在运行的进程之间进行通信的经验为零。到目前为止,我一直在读/写配置文件,每个实例都会读取和/或更新这些文件。
这是我编写的一些伪代码(某种简单的模板),让我思考如何解决这个问题。请尝试帮我填空。请记住,我没有套接字、线程等方面的经验……
import process # imaginary module
class AppA():
def __init__(self):
# Every instance that opens will need to attach
# itself to the "Instance Manager". If no manager
# exists, then we need to spawn it. Only one manager
# will ever exist no matter how many instances are
# running.
try:
hm = process.get_handle(AppA_InstanceManager)
except NoSuchProgError:
hm.spawn_instance(AppA_InstanceManager)
finally:
hm.register(self)
self.instance_manager = hm
def state_update(self):
# This method won't exist in the real code, however,
# it emulates internal state changes for the sake of
# explaination.
#
# When any internal state changes happen, we will then
# propagate the changes outward by calling the
# appropriate method of "self.instance_manager".
self.instance_manager.propagate_state()
def cb_state_update(self):
# Called from the "Instance Manager" only!
#
# This may be as simple as reading a known
# config file. Or could simply pass data
# to this method.
class AppA_InstanceManager():
def __init__(self):
self.instances = []
def register_instance(self, instance):
self.instances.append(instance)
def unregister_instance(self, instance):
# nieve example for now.
self.instances.remove(instance)
def propagate_state(self):
for instance in self.instances:
instance.cb_state_update(data)
if __name__ == '__main__':
app = AppA()
有什么建议吗?
请您参考如下方法:
这种设计有几种选择。
你可以使用消息队列,它是为这类东西而设计的,例如AMQP 或一些 ZeroMQ 或类似的东西。
或者您可以使用诸如 Redis 或其他(内存中)数据库之类的东西来进行同步。
如果你不想使用类似的东西,你可以使用多处理模块同步的东西。
或者使用特定于平台的 IPC 系统,例如通过 mmap、sysv 套接字等共享内存
如果你想按照你解释的方式做事,你可以看看 Twisteds perspective broker。
