TypeError: __init__() 得到了一个意外的关键字参数 'dir'

Question

I try to start a timer to do some file arvchival job. the code is like this:

from threading import Timer

message_archive_dir = "achivedir"
message_archive_format = "zip"
archive_timer = Timer(86400, messageachiver.archive, dir = message_archive_dir, fmt = message_archive_format)
archive_timer.start()


class messageachiver(object):
    def __init__(self, **kwargs):
            self.message_archive_dir = dir
            self.message_archive_format = fmt

    def archive(self):
            print("message_archive_dir is " + self.message_archive_dir)
            print("message_archive_format is " + self.message_archive_format)
            print("Archiving trade messages")

I got below error:

Traceback (most recent call last):
  File "sa_listener.py", line 43, in <module>
    archive_timer = Timer(archive_interval, messageachiver.archive, dir = message_archive_dir, fmt = message_archive_format)
TypeError: __init__() got an unexpected keyword argument 'dir'

I'm not sure why _ init _ does not accept **kwargs.

Answer 1

This specific init error is because you are passing multiple variables to the timer class.

In this line: Timer(86400, messageachiver.archive, dir = message_archive_dir, fmt = message_archive_format) You are passing the archive function, the dir variable, and the fmt variable to TIMER and not to the messageachiver class. Timer has no named variables for dir and fmt.

So the line should be Timer(86400, messageachiver.archive)

This only partially fixes your problem though. Because you are never actually initializing the class with the variables you need them to have. So before you call timer, you need to initialize the class messageachiver by adding mymessageachiver = messageachiver(dir = message_archive_dir, fmt = message_archive_format)

Also you need to put your class definition before you try to initialize it. The final code:

from threading import Timer

class messageachiver(object):
    def __init__(self, **kwargs):
            self.message_archive_dir = kwargs['dir']
            self.message_archive_format = kwargs['fmt']

    def archive(self):
            print("message_archive_dir is " + self.message_archive_dir)
            print("message_archive_format is " + self.message_archive_format)
            print("Archiving trade messages")


message_archive_dir = "achivedir"
message_archive_format = "zip"
mymessageachiver = messageachiver(dir = message_archive_dir, fmt = message_archive_format)
# That's a huge wait time, try something like 10 for a smaller wait during testing.
archive_timer = Timer(86400, mymessageachiver.archive) 
archive_timer.start()