Question

我正在使用cloudpickle传递函数，我想通过cloudpickle传递attrs类函数。

import pickle
import attr

@attr.s(auto_attribs=True)
class myclass:
    an_int: int
    a_str: str
    a_float: float

    def myfunc(self):
        return f"{self.an_int} + {self.a_str} + {self.a_float}"

mc = myclass(1, "test", 2.4)
f = pickle.loads(pickle.dumps(mc.myfunc))
print(f())

运行此命令可以给我1 + test + 2.4

实现云点刺

import attr
import cloudpickle

@attr.s(auto_attribs=True)
class myclass:
    an_int: int
    a_str: str
    a_float: float

    def myfunc(self):
        return f"{self.an_int} + {self.a_str} + {self.a_float}"

mc = myclass(1, "test", 2.4)
f = cloudpickle.loads(cloudpickle.dumps(mc.myfunc))
print(f())

给我错误：TypeError: can't pickle _thread._local objects（我将在底部显示完整的错误日志）

我有信心，我需要实现一些__getstate__或__reduce__函数来使泡菜腌制该类，但是我都尝试了两次而没有任何运气。

添加功能

def __reduce__(self):
    return (self.__class__, (self.an_int, self.a_str, self.a_float))

给出相同的错误

要实现此目标，我应该执行什么？

python错误日志：

Traceback (most recent call last):
  File "x.py", line 16, in <module>
    f = cloudpickle.loads(cloudpickle.dumps(mc.myfunc))
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/site-packages/cloudpickle/cloudpickle.py", line 917, in dumps
    cp.dump(obj)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/site-packages/cloudpickle/cloudpickle.py", line 268, in dump
    return Pickler.dump(self, obj)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 437, in dump
    self.save(obj)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 504, in save
    f(self, obj) # Call unbound method with explicit self
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/site-packages/cloudpickle/cloudpickle.py", line 689, in save_instancemethod
    self.save_reduce(types.MethodType, (obj.__func__, obj.__self__), obj=obj)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 638, in save_reduce
    save(args)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 504, in save
    f(self, obj) # Call unbound method with explicit self
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 771, in save_tuple
    save(element)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 549, in save
    self.save_reduce(obj=obj, *rv)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 633, in save_reduce
    save(cls)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 504, in save
    f(self, obj) # Call unbound method with explicit self
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/site-packages/cloudpickle/cloudpickle.py", line 664, in save_global
    return self.save_dynamic_class(obj)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/site-packages/cloudpickle/cloudpickle.py", line 511, in save_dynamic_class
    save(clsdict)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 504, in save
    f(self, obj) # Call unbound method with explicit self
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 856, in save_dict
    self._batch_setitems(obj.items())
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 882, in _batch_setitems
    save(v)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 504, in save
    f(self, obj) # Call unbound method with explicit self
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/site-packages/cloudpickle/cloudpickle.py", line 408, in save_function
    self.save_function_tuple(obj)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/site-packages/cloudpickle/cloudpickle.py", line 573, in save_function_tuple
    save(state)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 504, in save
    f(self, obj) # Call unbound method with explicit self
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 856, in save_dict
    self._batch_setitems(obj.items())
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 882, in _batch_setitems
    save(v)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 504, in save
    f(self, obj) # Call unbound method with explicit self
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 856, in save_dict
    self._batch_setitems(obj.items())
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 882, in _batch_setitems
    save(v)
  File "/home/me/.local/share/pyenv/versions/3.7.0/lib/python3.7/pickle.py", line 524, in save
    rv = reduce(self.proto)
TypeError: can't pickle _thread._local objects

Answer 1

这是由于attrs使用线程局部变量破坏__repr__中的对象周期而导致的。供参考，它是在https://github.com/python-attrs/attrs/pull/358中引入的。

您的快速解决方案是设置@attr.s(repr=False)，但是随时可以在我们的错误跟踪器上打开一个问题，我们可以讨论如何继续。

如何通过cloudpickle腌制python-attrs类函数？

1 个答案: