Django - how do you turn an InMemoryUploadedFile into an ImageField ?

Question

I've been trying help(django.db.models.ImageField) and dir(django.db.models.ImageField), looking for how you might create a ImageField object from an image that is uploaded.

request.FILES has the images as InMemoryUploadedFile, but I'm trying to save a model that contains an ImageField, so how do I turn the InMemoryUploadedFile into the ImageField?

How do you go about finding this type of thing out? I suspect that the two classes have an inheritance relationship, but I'd have to do lots of dir() -ing to find out if I were to look.

Answer 1

You trying to do it in ModelForm?

This is how i did for file field

class UploadSongForm(forms.ModelForm):
    class Meta:
        model = Mp3File

    def save(self):
        content_type = self.cleaned_data['file'].content_type
        filename = gen_md5() + ".mp3"
        self.cleaned_data['file'] = SimpleUploadedFile(filename, self.cleaned_data['file'].read(), content_type)
        return super(UploadSongForm, self).save()

You can take it as example and look in source what InMemoryUploadedFile class needs in initialization parameters.

Answer 2

If the documentation falls short, take a look at the Django source code.

I mean really.

It's mostly quite readable and you'll obtain better understanding of the system than by only poking with help() and dir().

Answer 3

You could implement a form with a file upload field by using form instances, here is the view:

def form_view(request):
    if request.method == 'POST':
        form = FooForm(request.POST, request.FILES)
        if form.is_valid():
            form.save()
            return render_to_response('result.html')
        return render_to_response('form.html', {
            'form': form;
            'error_messages': form.errors;
        }
    form = FooForm()
    return render_to_response('form.html', {
        'form': form;
    }

form.save() saves the uploaded file along with all the other fields as you included request.FILES argument in it's constructor. In your models you have to define FooForm subclass of ModelForm class like this:

class FooForm(ModleForm):
    Meta:
        model = Foo

...where Foo is the subclass of Model, that describes the data you want to store persistently.

Answer 4

You need to save the InMemoryUploadedFile to the ImageField rather than 'turning' it into an ImageField:

image = request.FILES['img']
foo.imagefield.save(image.name, image)

where foo is the model instance, and imagefield is the ImageField.

Alternatively, if you are pulling the image out of a form:

image = form.cleaned_data.get('img')
foo.imagefield.save(image.name, image)