view and forms

view.py

from django.shortcuts import render, redirect
from django.contrib.auth.decorators import login_required
from django.contrib import messages
from .forms import ImageCreateForm


@login_required
def image_create(request):
    if request.method == 'POST':
        # form is sent
        form = ImageCreateForm(data=request.POST)
        if form.is_valid():
            # form data is valid
            cd = form.cleaned_data
            new_item = form.save(commit=False)
            # assign current user to the item
            new_item.user = request.user
            new_item.save()
            messages.success(request, 'Image added successfully')
            # redirect to new created item detail view
            return redirect(new_item.get_absolute_url())
        else:
            # build form with data provided by the bookmarklet via GET
            form = ImageCreateForm(data=request.GET)
        return render(request,
                    'images/image/create.html',
                        {'section': 'images',
                        'form': form})

forms.py

from django import forms
from .models import Image
from urllib import request
from django.core.files.base import ContentFile
from django.utils.text import slugify

class ImageCreateForm(forms.ModelForm):
    class Meta:
        model = Image
        fields = ('title', 'url', 'description' )
        widgets = {
            'url': forms.HiddenInput,
        }
    def clean_url(self):
        url = self.cleaned_data['url']
        valid_extensions = ['jpg', 'jpeg']
        extension = url.rsplit('.', 1)[1].lower()
        if extension not in valid_extensions:
            raise forms.ValidationError('The given URL does not'
                                        'match valid image extensions.')
        return url

    def save(self, force_insert=False, force_update=False, commit=True):
        image = super(ImageCreateForm, self).save(commit=False)
        image_url = self.cleaned_data['url']
        image_name = '{}.{}'.format(slugify(image.title),
                                    image_url.rsplit('.', 1)[1].lower())
        response = request.urlopen(image_url)
        image.image.save(image_name, ContentFile(response.read()), save=False)
        if commit:
            image.save()
        return image