Create a Python image in Django without a dummy image file and test the image upload

You can test the upload even if you put the image file locally, but to complete it in the test code.

Create sample application

(python2.7, django1.6)

$ django-admin.py startproject core
$ mv core photo_book
$ cd photo_book
$ python manage.py startapp photos
$ mkdir -p static/upload  #Directory to save images

core/

settings.py

#Only additional parts
IINSTALLED_APPS = (
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'photos',  #add to
)

MEDIA_ROOT = os.path.join(BASE_DIR, 'static/')  #add to

urls.py

from django.conf.urls import patterns, include, url

from django.contrib import admin
admin.autodiscover()

from photos.views import ImageCreateView

urlpatterns = patterns(
    '',
    url(r'^images/$', ImageCreateView.as_view(), name='images'),
    url(r'^admin/', include(admin.site.urls)),
)

photos/

model

models.py

from django.db import models


class Photo(models.Model):
    image = models.ImageField(upload_to='upload')

Form

forms.py

from django import forms


class PhotoForm(forms.Form):
    image = forms.ImageField()

View

views.py

from django.views.generic.edit import CreateView

from photos.models import Photo


class ImageCreateView(CreateView):
    model = Photo
    success_url = '/'

test

test.py

from StringIO import StringIO

from django.core.urlresolvers import reverse
from django.test import TestCase
from photos.models import Photo


class CreateImageTest(TestCase):
    def test_post(self):
        url = reverse("images")

        dummy_image = StringIO(
            'GIF87a\x01\x00\x01\x00\x80\x01\x00\x00\x00\x00ccc,\x00'
            '\x00\x00\x00\x01\x00\x01\x00\x00\x02\x02D\x01\x00;'
        )
        dummy_image.name = 'dummy_image.gif'
        dummy_image.content_type = 'image/gif'
        response = self.client.post(url, {'image': dummy_image})

        self.assertEqual(response.status_code, 302)
        #Check if it was saved in db
        self.assertEqual(Photo.objects.count(), 1)
        #Check if the saved image and the uploaded dummy image are the same
        uploaded_image = StringIO(open(Photo.objects.last().image._get_path(), 'rb').read())
        self.assertEqual(uploaded_image.getvalue(), dummy_image.getvalue())

Test run

$ python manage.py test
Creating test database for alias 'default'...
.
----------------------------------------------------------------------
Ran 1 test in 0.042s

OK
Destroying test database for alias 'default'...

reference

• http://stackoverflow.com/questions/2473392/unit-testing-a-django-form-with-a-filefield
• http://stackoverflow.com/questions/22535240/in-django-which-format-does-models-imagefield-take-by-default