Django - How to Save ImageField Even if Form is Not Valid - django

Question

I have a fairly standard model and form. I have some mandatory fields with an ImageField. When the user choose an image and doesn't field the mandatory fields, the image isn't saved and the user needs to 're-upload' it again.
As the row in the database already exists (because this form is part of a 'wizard'), I don't mind saving the picture in the database even if all the form isn't valid with all the mandatory data.
This is what I have right now in my view, which works when you fill all the mandatory fields:
def my_view(request):
instance = MyModel.objects.get(user=request.user)
form = MyForm(instance=instance)
if request.POST:
form = MyForm(request.POST, request.FILES, instance=instance)
if form.is_valid():
new_instance = form.save(commit=False)
if request.FILES and request.FILES['photo']:
uploaded_photo = request.FILES['photo']
new_instance.photo = uploaded_photo
new_instance.save()
return HttpResponseRedirect(reverse('new_url'))
return render_to_response('current_template.html', locals(), context_instance=RequestContext(request))
Here's what I tried to save the picture in DB even if the other fields aren't filled, but I get the error Django Upload Error - Upload a valid image (either not an image or corrupted):
def my_view(request):
instance = MyModel.objects.get(user=request.user)
form = MyForm(instance=instance)
if request.POST:
form = MyForm(request.POST, request.FILES, instance=instance)
if request.FILES and request.FILES['photo']:
uploaded_photo = request.FILES['photo']
instance.photo = uploaded_photo
instance.save()
if form.is_valid():
new_instance = form.save()
return HttpResponseRedirect(reverse('new_url'))
return render_to_response('current_template.html', locals(), context_instance=RequestContext(request))
Here's my form (fairly simple):
class MyForm(ModelForm):
first_name = forms.CharField(label='First Name', max_length=50, required=True)
last_name = forms.CharField(label='Last Name', max_length=50, required=True)
photo = forms.ImageField(required=False)
def __init__(self, *args, **kwargs):
super(MyForm, self).__init__(*args, **kwargs)
class Meta:
model = MyModel
fields = ('first_name','last_name', 'photo')
Here's my model (again very simple):
class MyModel(models.Model):
first_name = models.TextField(max_length=50)
last_name = models.TextField(max_length=50)
photo = ImageField(upload_to=get_photo_path,null=True,blank=True)

Answer 1

This is how I made it work. Notice that there's no 'request.FILES' as a parameter for the constructor of the form in the 'else' when the form is not valid. This is what made Django display the error message.
if form.is_valid():
instance = form.save(commit=False)
if request.FILES and request.FILES['photo']:
instance = save_photo(instance, request.FILES['photo'])
instance.save()
return HttpResponseRedirect(reverse('url'))
else:
if request.FILES and request.FILES['photo']:
instance = save_photo(instance, request.FILES['photo'])
form = InstanceForm(request.POST, instance=instance)