[Fixed]-How to unit test a form with a captcha field in django?

I know this is an old post, but django-simple-captcha now has a setting CAPTCHA_TEST_MODE which makes the captcha succeed if you supply the value ‘PASSED’. You just have to make sure to send something for both of the captcha input fields:

post_data['captcha_0'] = 'dummy-value'
post_data['captcha_1'] = 'PASSED'
self.client.post(url, data=post_data)

The CAPTCHA_TEST_MODE setting should only be used during tests. My settings.py:

if 'test' in sys.argv:
    CAPTCHA_TEST_MODE = True 

I unit tested it by mocking the ReCaptchaField. First, I’ve added the recaptcha field in the constructor. It cannot be added as a regular field because you won’t be able to mock it (once the code is evaluated before the mock is being applied):

class MyForm(forms.ModelForm):

    ...

    def __init__(self, *args, **kwargs):
        # Add captcha in the constructor to allow mock it
        self.fields["captcha"] = ReCaptchaField()

Then, I just replaced the ReCaptchaField by a not required CharField. This way, I’m trusting django-recaptcha will work. I can test only my own stuff:

@mock.patch("trials.forms.ReCaptchaField", lambda: CharField(required=False))
def test_my_stuff(self):
    response = self.client.post(self.url, data_without_captcha)
    self.assert_my_response_fit_the_needs(response)

Here is how we do it.

@patch("captcha.fields.ReCaptchaField.validate")
def test_contact_view(self, validate_method):

    response = self.client.get(reverse("contact"))
    self.assertEqual(response.status_code, 200)

    data = {
        "name": "Bob Johnson",
        "email": "big_johnson@home.com",
        "phone": "800-212-2001",
        "subject": "I want Axis!",
        "message": "This is a giant\nThree liner..\nLove ya\n",
        "captcha": "XXX",
    }
    validate_method.return_value = True
    response = self.client.post(reverse("contact"), data=data)

    self.assertEqual(response.status_code, 302)

One solution is have a setting “testing” that is either true or false. And then just

if not testing:
   # do captcha stuff here

It’s simple and easy, and an easy toggle.

Another solutions which is similar to Jim McGaw’s answer but remove the need of empty table CaptchaStore table.

captcha = CaptchaStore.objects.get(hashkey=CaptchaStore.generate_key())

registration_data = { # other registration data here
                 'captcha_0': captcha.hashkey,
                 'captcha_1': captcha.response }

This will generate new captcha just for that test.

Here is the only thing that worked for me,

set the CAPTCHA_TEST_MODE=True in the test setup method.

class ApplicationTestCase(TestCase):
    def setUp(self):
        self.client = Client()
        self.url = reverse('application')
        from captcha.conf import settings as captcha_settings
        captcha_settings.CAPTCHA_TEST_MODE = True
    
    def test_post_valid_form(self):
        data = {
            'name': 'John Doe',
            "captcha_0": "8e10ebf60c5f23fd6e6a9959853730cd69062a15",
            "captcha_1": "PASSED",
        }

        response = self.client.post(self.url, data)
        self.assertEqual(response.status_code, 200)

With a similar approach than Jim McGaw but using BeautifulSoup:

from captcha.models import CaptchaStore
from BeautifulSoup import BeautifulSoup

data = {...} #The data to post
soup = BeautifulSoup(self.client.get(url).content)
for field_name in ('captcha_0', ...): #get fields from the form
    data[field_name] = soup.find('input',{'name':field_name})['value']
captcha = CaptchaStore.objects.get(hashkey=data['captcha_0'])
data['captcha_1'] = captcha.challenge
response = self.client.post(url, data=data)

# check the results
...