连接到 Multiprocessing BaseManager 在本地工作，但不适用于远程服务器

Question

我目前正在使用multiprocessing.managers.BaseManager功能来提供一些 Python 对象，以便我可以在客户端与它们的代理进行交互。

启动 BaseManager 定义的服务器后，我尝试在客户端连接以访问可服务对象。 但是，只有当服务器和客户端存在于不同的主机上时，我才会看到EoFError 。 如果他们在同一个本地主机上，我可以很好地访问。

服务器.py

from multiprocessing.managers import BaseManager
password = "password".encode("utf-8")

class MyManager(BaseManager):
    pass

a = {'one': 1}  # to be served
MyManager.register("get_a", callable=lambda: a)
m = MyManager(address=("127.0.0.1", 60000), authkey=password)
m.start()
# ... long running process ...

客户端.py

from multiprocessing.managers import BaseManager
password = "password".encode("utf-8")

class MyManager(BaseManager):
    pass

MyManager.register("get_a")
manager = MyManager(address=("SERVER_IP", 60000), authkey=password)
manager.connect()  # raises EoFError

追溯：

File "client.py", line 20, in connect_to_executor_manager
               manager.connect()
File "/usr/lib/python3.7/multiprocessing/managers.py", line 512, in connect
              conn = Client(self._address, authkey=self._authkey)
File "/usr/lib/python3.7/multiprocessing/connection.py", line 498, in Client
            answer_challenge(c, authkey)
File "/usr/lib/python3.7/multiprocessing/connection.py", line 741, in answer_challenge
              message = connection.recv_bytes(256)         # reject large message
File "/usr/lib/python3.7/multiprocessing/connection.py", line 216, in recv_bytes
            buf = self._recv_bytes(maxlength)
File "/usr/lib/python3.7/multiprocessing/connection.py", line 407, in _recv_bytes
          buf = self._recv(4)
File "/usr/lib/python3.7/multiprocessing/connection.py", line 383, in _recv
          raise EOFError

Answer 1

我刚刚遇到了同样的问题，但幸运的是，我在调试过程中修改代码时创造了一个线索

from multiprocessing.managers import BaseManager
password = "password".encode("utf-8")

class MyManager(BaseManager):
    pass

a = {'one': 1}  # to be served
MyManager.register("get_a", callable=lambda: a)
m = MyManager(address=("127.0.0.1", 60000), authkey=password)
print(f"serving at address {m.address}")      # I added the equivalent of this line
m.start()

我的测试代码导致“在地址服务...”行打印两次。 这让我觉得代码被生成了两次。 我记得在某处看到服务器代码应该包含在if __name__ ==...块中，所以我尝试了，事情开始工作了。
我不是专家，但我认为这个错误是在产卵/分叉/等过程中引起的。 过程。 长话短说，您可以像这样修改您的server.py代码，它可能会起作用。

from multiprocessing.managers import BaseManager
password = "password".encode("utf-8")

class MyManager(BaseManager):
    pass

a = {'one': 1}  # to be served
MyManager.register("get_a", callable=lambda: a)

if __name__ == '__main__':
    m = MyManager(address=("127.0.0.1", 60000), authkey=password)
    m.start()