How do I get Django Admin to delete files when I remove an object from the database/model?

Question

I am using 1.2.5 with a standard ImageField and using the built-in storage backend. Files upload fine but when I remove an entry from admin the actual file on the server does not delete.

Answer 1

You can receive the pre_delete or post_delete signal (see @toto_tico's comment below) and call the delete() method on the FileField object, thus (in models.py):

class MyModel(models.Model):
    file = models.FileField()
    ...

# Receive the pre_delete signal and delete the file associated with the model instance.
from django.db.models.signals import pre_delete
from django.dispatch.dispatcher import receiver

@receiver(pre_delete, sender=MyModel)
def mymodel_delete(sender, instance, **kwargs):
    # Pass false so FileField doesn't save the model.
    instance.file.delete(False)

Answer 2

Try django-cleanup

pip install django-cleanup

settings.py

INSTALLED_APPS = (
    ...
    'django_cleanup.apps.CleanupConfig',
)

Answer 3

Django 1.5 solution: I use post_delete for various reasons that are internal to my app.

from django.db.models.signals import post_delete
from django.dispatch import receiver

@receiver(post_delete, sender=Photo)
def photo_post_delete_handler(sender, **kwargs):
    photo = kwargs['instance']
    storage, path = photo.original_image.storage, photo.original_image.path
    storage.delete(path)

I stuck this at the bottom of the models.py file.

the original_image field is the ImageField in my Photo model.

Answer 4

This code runs well on Django 1.4 also with the Admin panel.

class ImageModel(models.Model):
    image = ImageField(...)

    def delete(self, *args, **kwargs):
        # You have to prepare what you need before delete the model
        storage, path = self.image.storage, self.image.path
        # Delete the model before the file
        super(ImageModel, self).delete(*args, **kwargs)
        # Delete the file after the model
        storage.delete(path)

It's important to get the storage and the path before delete the model or the latter will persist void also if deleted.

Answer 5

You need to remove the actual file on both delete and update.

from django.db import models

class MyImageModel(models.Model):
    image = models.ImageField(upload_to='images')

    def remove_on_image_update(self):
        try:
            # is the object in the database yet?
            obj = MyImageModel.objects.get(id=self.id)
        except MyImageModel.DoesNotExist:
            # object is not in db, nothing to worry about
            return
        # is the save due to an update of the actual image file?
        if obj.image and self.image and obj.image != self.image:
            # delete the old image file from the storage in favor of the new file
            obj.image.delete()

    def delete(self, *args, **kwargs):
        # object is being removed from db, remove the file from storage first
        self.image.delete()
        return super(MyImageModel, self).delete(*args, **kwargs)

    def save(self, *args, **kwargs):
        # object is possibly being updated, if so, clean up.
        self.remove_on_image_update()
        return super(MyImageModel, self).save(*args, **kwargs)

Answer 6

You may consider using a pre_delete or post_delete signal:

https://docs.djangoproject.com/en/dev/topics/signals/

Of course, the same reasons that FileField automatic deletion was removed also apply here. If you delete a file that is referenced somewhere else you will have problems.

In my case this seemed appropriate because I had a dedicated File model to manage all of my files.

Note: For some reason post_delete doesn't seem to work right. The file got deleted, but the database record stayed, which is completely the opposite of what I would expect, even under error conditions. pre_delete works fine though.

Answer 7

Maybe it's a little late. But the easiest way for me is to use a post_save signal. Just to remember that signals are excecuted even during a QuerySet delete process, but the [model].delete() method is not excecuted during the QuerySet delete process, so it's not the best option to override it.

core/models.py:

from django.db import models
from django.db.models.signals import post_delete
from core.signals import delete_image_slide
SLIDE1_IMGS = 'slide1_imgs/'

class Slide1(models.Model):
    title = models.CharField(max_length = 200)
    description = models.CharField(max_length = 200)
    image = models.ImageField(upload_to = SLIDE1_IMGS, null = True, blank = True)
    video_embed = models.TextField(null = True, blank = True)
    enabled = models.BooleanField(default = True)

"""---------------------------- SLIDE 1 -------------------------------------"""
post_delete.connect(delete_image_slide, Slide1)
"""--------------------------------------------------------------------------"""

core/signals.py

import os

def delete_image_slide(sender, **kwargs):
    slide = kwargs.get('instance')
    try:
        os.remove(slide.image.path)
    except:
        pass

Answer 8

Using the post_delete is for sure the right way to go. Sometimes though things can go wrong, and files don't get deleted. There is of course the case that you have a bunch of old files that weren't deleted before post_delete was used. I created a function that deletes files for objects based on if the file the object references does not exist then delete object, if the file does not have an object, then also delete, also it can delete based on an "active" flag for an object.. Something I added to most of my models. You have to pass it the objects you want to check, the path to the objects files, the file field and a flag to delete inactive objects:

def cleanup_model_objects(m_objects, model_path, file_field='image', clear_inactive=False):
    # PART 1 ------------------------- INVALID OBJECTS
    #Creates photo_file list based on photo path, takes all files there
    model_path_list = os.listdir(model_path)

    #Gets photo image path for each photo object
    model_files = list()
    invalid_files = list()
    valid_files = list()
    for obj in m_objects:

        exec("f = ntpath.basename(obj." + file_field + ".path)")  # select the appropriate file/image field

        model_files.append(f)  # Checks for valid and invalid objects (using file path)
        if f not in model_path_list:
            invalid_files.append(f)
            obj.delete()
        else:
            valid_files.append(f)

    print "Total objects", len(model_files)
    print "Valid objects:", len(valid_files)
    print "Objects without file deleted:", len(invalid_files)

    # PART 2 ------------------------- INVALID FILES
    print "Files in model file path:", len(model_path_list)

    #Checks for valid and invalid files
    invalid_files = list()
    valid_files = list()
    for f in model_path_list:
        if f not in model_files:
            invalid_files.append(f)
        else:
            valid_files.append(f)
    print "Valid files:", len(valid_files)
    print "Files without model object to delete:", len(invalid_files)

    for f in invalid_files:
        os.unlink(os.path.join(model_path, f))

    # PART 3 ------------------------- INACTIVE PHOTOS
    if clear_inactive:
        #inactive_photos = Photo.objects.filter(active=False)
        inactive_objects = m_objects.filter(active=False)
        print "Inactive Objects to Delete:", inactive_objects.count()
        for obj in inactive_objects:
            obj.delete()
    print "Done cleaning model."

This is how you can use this:

photos = Photo.objects.all()
photos_path, tail = ntpath.split(photos[0].image.path)  # Gets dir of photos path, this may be different for you
print "Photos -------------->"
cleanup_model_objects(photos, photos_path, file_field='image', clear_inactive=False)  # image file is default

Answer 9

This functionality will be removed in Django 1.3 so I wouldn't rely on it.

You could override the delete method of the model in question to delete the file before removing the entry from the database completely.

Edit:

Here is a quick example.

class MyModel(models.Model):

    self.somefile = models.FileField(...)

    def delete(self, *args, **kwargs):
        somefile.delete()

        super(MyModel, self).delete(*args, **kwargs)

Answer 10

make sure you write "self" before the file. so example above should be

def delete(self, *args, **kwargs):
        self.somefile.delete()

        super(MyModel, self).delete(*args, **kwargs)

I've forgotten the "self" before my file and that didn't work as it was looking in the global namespace.

Answer 11

If you already have number of unused files in your project and want to delete them, you can use django utility django-unused-media

Answer 12

Django 2.x Solution:

There's no need to install any packages! It's very easy to handle in Django 2. I've tried following solution using Django 2 and SFTP Storage (however I think it would work with any storages)

First write a Custom Manager. So if you want to be able to delete files of a model by using objects methods, you must write and use a [Custom Manager][3] (for overriding delete() method of objects):

class CustomManager(models.Manager):
    def delete(self):
        for obj in self.get_queryset():
            obj.delete()

Now you must delete image before deleting deleting the model itself and for assigning the CustomManager to the model, you must initial objects inside your model:

class MyModel(models.Model):
    image = models.ImageField(upload_to='/pictures/', blank=True)
    objects = CustomManager() # add CustomManager to model
    def delete(self, using=None, keep_parents=False):

    objects = CustomManager() # just add this line of code inside of your model

    def delete(self, using=None, keep_parents=False):
        self.image.storage.delete(self.song.name)
        super().delete()

Answer 13

I may have a special case since I am using the upload_to option on my file field with dynamic directory names but the solution I found was to use os.rmdir.

In models:

import os

...

class Some_Model(models.Model):
     save_path = models.CharField(max_length=50)
     ...
     def delete(self, *args,**kwargs):
          os.rmdir(os.path.join(settings.MEDIA_ROOT, self.save_path)
          super(Some_Model,self).delete(*args, **kwargs)