[FIXED] Django: how to check if a field has been modified by the user?

Issue

I have a model in models.py; like this:

class Profile(models.Model):
    user   = models.OneToOneField(User, on_delete=models.CASCADE)
    avatar = models.ImageField(upload_to='static/images/account/avatar', default='/static/images/default-avatar.png')
    bio    = models.CharField(max_length=300, blank=True, null=True)

    def __str__(self):
        return '@' + self.user.username

in views.py i want to check if a filed (i mean avatar) from Profile model has changed or not in views.py:

def editProfile(request):
    user = request.user.profile
    form = AuthorForm(instance=user)
    if request.method == 'POST':
        if ...:
            os.remove(request.user.profile.avatar.path)
        form = AuthorForm(request.POST, request.FILES, instance=user)
        if form.is_valid():
            form.save()
            return redirect('dashboard')
    context = {'form': form}
    
    return render(request, 'account/edit.html', context)

In fact, I want the default image (or any other photo) not to be deleted if the user does not change the avatar field.

Solution

The fields that change are listed in the .changed_data attribute [Django-doc]. You thus can check if the avatar has changed with:

if 'avatar' in form.changed_data:
    os.remove(request.user.profile.avatar.path)

Answered By - Willem Van Onsem