Using django-simple-captcha#
Installation#
Install
django-simple-captcha
via pip:pip install django-simple-captcha
Add
captcha
to theINSTALLED_APPS
in yoursettings.py
Run
python manage.py migrate
Add an entry to your
urls.py
:urlpatterns += [ path('captcha/', include('captcha.urls')), ]
Note: Pillow requires that image libraries are installed on your system. On e.g. Debian or Ubuntu, you’d need these packages to compile and install Pillow:
apt-get -y install libz-dev libjpeg-dev libfreetype6-dev python-dev
Adding to a Form#
Using a CaptchaField
is quite straight-forward:
Define the Form#
To embed a CAPTCHA in your forms, simply add a CaptchaField
to the form definition:
from django import forms
from captcha.fields import CaptchaField
class CaptchaTestForm(forms.Form):
myfield = AnyOtherField()
captcha = CaptchaField()
…or, in a ModelForm
:
from django import forms
from captcha.fields import CaptchaField
class CaptchaTestModelForm(forms.ModelForm):
captcha = CaptchaField()
class Meta:
model = MyModel
Validate the Form#
In your view, validate the form as usual. If the user didn’t provide a valid response to the CAPTCHA challenge, the form will raise a ValidationError
and display an error message to the user:
def some_view(request):
if request.POST:
form = CaptchaTestForm(request.POST)
# Validate the form: the captcha field will automatically
# check the input
if form.is_valid():
human = True
else:
form = CaptchaTestForm()
return render(request, 'template.html', {'form': form})
Passing arguments to the field#
CaptchaField
takes a few optional arguments:
output_format
will let you format the layout of the rendered field. Defaults to the value defined in : output_format_ref.id_prefix
Optional prefix that will be added to the ID attribute in the generated fields and labels, to be used when e.g. several Captcha fields are being displayed on a same page. (added in version 0.4.4)generator
Optional callable or module path to callable that will be used to generate the challenge and the response, e.g.generator='path.to.generator_function'
orgenerator=lambda: ('LOL', 'LOL')
, see also Generators and modifiers. Defaults to whatever is defined insettings.CAPTCHA_CHALLENGE_FUNCT
.
Example usage for ajax form#
An example CAPTCHA validation in AJAX:
from django.views.generic.edit import CreateView
from captcha.models import CaptchaStore
from captcha.helpers import captcha_image_url
from django.http import HttpResponse
import json
class AjaxExampleForm(CreateView):
template_name = ''
form_class = AjaxForm
def form_invalid(self, form):
if self.request.is_ajax():
to_json_response = dict()
to_json_response['status'] = 0
to_json_response['form_errors'] = form.errors
to_json_response['new_cptch_key'] = CaptchaStore.generate_key()
to_json_response['new_cptch_image'] = captcha_image_url(to_json_response['new_cptch_key'])
return HttpResponse(json.dumps(to_json_response), content_type='application/json')
def form_valid(self, form):
form.save()
if self.request.is_ajax():
to_json_response = dict()
to_json_response['status'] = 1
to_json_response['new_cptch_key'] = CaptchaStore.generate_key()
to_json_response['new_cptch_image'] = captcha_image_url(to_json_response['new_cptch_key'])
return HttpResponse(json.dumps(to_json_response), content_type='application/json')
And in javascript your must update the image and hidden input in form
Example usage ajax refresh#
# javascript:
$('.captcha').click(function () {
$.getJSON("/captcha/refresh/", function (result) {
$('.captcha').attr('src', result['image_url']);
$('#id_captcha_0').val(result['key'])
});
});