Hi akaariai As you said i will remove the file and leave the file in file system(mistake for writing delete). Now what i have done is :-
image: Currently: images/testimonial-bottom_2.png<http://localhost:8000/media/images/testimonial-bottom_2.png> Change: Delete this file When you click the link Delete this file what it will do is it will remove the path "images/testimonial-bottom_2.png<http://localhost:8000/media/images/testimonial-bottom_2.png>".But the problem begins when you press save button and open the same row in django - admin it appears again as if it was not removed and actually it is not removed from that ImageField . i have checked by going through shell. Actually i want implement ImageField of Django1.4b . It has a checkbox(remove_image) along with the ImageField asking for clear image and when you click on that the image get removed. How can i get the same thing working for Django1.2.5 which i am using. So i thought to make a checkbox ,click on that it will trigger a post_save signal which first looks if the checkbox of remove_image is checked and when save button is pressed it wil remove the path of image. How can i implement that ? Thanks for help in advance . On Sun, Mar 4, 2012 at 6:22 PM, akaariai <akaar...@gmail.com> wrote: > > On Sunday, March 4, 2012 12:31:50 PM UTC+2, Nikhil Verma wrote: >> >> Hi all >> >> I am using Django-1.2.5 and i want to use post_save signal in the >> following problem/task. >> >> I have :- >> models.py >> >> image = models.ImageField(.....) >> remove_image = models.BooleanField() >> >> Now i want :- >> >> 1) When the user uploads the file , the file path appears on the >> imageField like this. >> >> Currently: >> images/testimonial-bottom_1.**png<http://localhost:8000/media/images/testimonial-bottom_1.png> >> >> Change: >> >> I want to give the option to delete the file .So i made a field called >> remove image which is a checkbox . Now when the user clicks that >> remove_image checkbox and press save the image should get deleted. I was >> going through the documentation and believe that this problem could be >> solved by using post_save signal >> >> >> I have not used signals so need help , >> >> >> def delete_old_image(sender, instance, using=None,*args, **kwargs): >> try: >> old_record = sender.objects.get(pk=instance**.pk<http://instance.pk> >> ) >> old_record.delete() >> except sender.DoesNotExist: >> pass >> signals.post_save.connect(**delete_old_image, sender=Trip) >> >> How can i achieve this task by using signals or without signals. >> >> Any help will be appreciated. >> >> You have a misunderstanding in your code: when you fetch the old_record > from sender.objects you are actually refetching the instance being saved. > Then you do on to delete the instance. Is this really what you want? > > Now, if you want to delete the file in a signal, you should use pre_save > signal, where you delete the image using instance.image.delete(save=False) > or better jet set instance.image = None (see later for details). You should > probably also clear the "save" flag, as otherwise that gets saved into the > DB. > > Still, it is much better to handle the clearing of the image field by > using a custom form, and then do the clearing of the image in some hook of > the form or in the view directly (for ModelForm that would be overridden > .save()). The checkbox remove_image isn't really part of your data model, > so it should not be a field in you model class, just a user input element. > > Last, for some technicalities about file handling in transactional > setting: To do file handling properly when using transactional databases > you should actually do the file delete post-commit. The reason is this > sequence of events: > - delete file > - do save > - for some reason the transaction is rolled back. (network error, > integrity error in DB, electricity lost and so on). > > Now you have a model in the DB whose file field points to the now deleted > file. The delete can't be rolled back. > > So, to be technically correct, you should do the .delete() in post-commit > hook. Now the worst case is that the transaction gets committed, but for > some reason the file can't be deleted (crash of the server at the wrong > moment). But, this results just in a leftover file in the storage. That is > easy to clean up and in most cases doesn't matter at all. > > As said, this is just a technicality. Django doesn't even provide that > post-commit hook. I think I am going to suggest a pre/post commit signal, > that could have other uses, too... However: there is a lesson here: are you > sure you want to actually delete the actual file? You could just remove the > link from the instance to that file, but leave the file in the file system. > > - Anssi > > -- > You received this message because you are subscribed to the Google Groups > "Django users" group. > To view this discussion on the web visit > https://groups.google.com/d/msg/django-users/-/j3k9QXOZkYcJ. > To post to this group, send email to django-users@googlegroups.com. > To unsubscribe from this group, send email to > django-users+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/django-users?hl=en. > -- Regards Nikhil Verma +91-958-273-3156 -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
