Question

使用以下代码会导致：

'Collection' object is not callable. If you meant to call the '__getnewargs__' method on a 'Collection' object it is failing because no such method exists.

代码：来自多处理导入池 db = MongoClient（ip，port）

def f(cursor, arg):
    for doc in cursor:
       ...

p = Pool(4)
for arg in args:
    cursor = db[dbName][collName].find()
    p.apply_async(f,[cursor, arg])

db.close()

无法弄清问题是什么以及如何调试代码。

完整追溯：

Exception in thread Thread-2:
Traceback (most recent call last):
  File "C:\Python27\lib\threading.py", line 808, in __bootstrap_inner
    self.run()
  File "C:\Python27\lib\threading.py", line 761, in run
    self.__target(*self.__args, **self.__kwargs)
  File "C:\Python27\lib\multiprocessing\pool.py", line 342, in _handle_tasks
    put(task)
  File "C:\Python27\lib\site-packages\pymongo\collection.py", line 1489, in __call__
    self.__name.split(".")[-1])
TypeError: 'Collection' object is not callable. If you meant to call the '__getnewargs__' method on a 'Collection' object it is failing because no such method exists.

Answer 1

您在使用cursor时遇到问题。 Collection.find方法返回一个Cursor对象，它是一个消耗品。（http://api.mongodb.org/python/current/api/pymongo/cursor.html#pymongo.cursor.Cursor.getitem）我不知道这是否是异常的原因，但肯定是个问题。

两种解决方案：

使用[:]或list
将光标放在apply_async中并使用clone方法克隆光标（http://api.mongodb.org/python/current/api/pymongo/cursor.html#pymongo.cursor.Cursor.clone）

“进程池”中的“集合”对象在pymongo中不可调用错误

1 个答案: