问题描述
我已经使用@receiver装饰器在回调函数中注册了信号
I have registered my signal with the callback using the @receiver decorator
@receiver(post_save, sender=User, dispatch_uid='ARandomUniqueString')
def do_callback(sender, **kwargs):
我已经将from app.signals import *代码放入了__init__.py中，并且可以看到它被导入了两次，并且我认为没有很好的方法来修复它，这可能是由于settings.py中的installed apps导致的.我不明白为什么尽管使用dispatch_uid并且modelInstance.save仅被调用一次，却仍然运行do_callback两次.有什么建议吗?
I have put the from app.signals import * code in __init__.py and I can see that it gets imported twice and I do not think there is a good way to fix it, possibly happening due to installed apps in settings.py. I cannot understand why despite using dispatch_uid and the modelInstance.save being invoked only once, it still runs do_callback twice. Any suggestions?
推荐答案
好，所以我将导入移动到了views.py(或models.py，并且只导入了一次，却被调用了两次).
Ok so I moved the import to views.py (or models.py and while it was getting imported only once, it was getting called twice.
问题是在创建和保存对象时会调用post_save信号.我不知道为什么，所以我添加了一个现在可以解决的解决方法
The problem was that the post_save signal was getting called when the object was created as well as saved. I have no idea why so I added a workaround which now works
created = False
#Workaround to signal being emitted twice on create and save
if 'created' in kwargs:
if kwargs['created']:
created=True
#If signal is from object creation, return
if created:
return
post_save被调用了两次，因为我使用了.create(...)，它等同于__init__(...)和.save().
post_save was getting called twice because I used .create(...) which is equivalent to __init__(...) and .save().
结论
dispatch_uid确实有效，并且单次导入仍然是一个好习惯.
dispatch_uid does work and doing single imports is still a good practice.
这篇关于尽管存在uid，但Django post save信号被调用了两次的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！