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Implementing reCAPTCHA v2 after Simple Captcha

This article details the steps you need to take in order to modify your existing Captcha to reCAPTCHA.

Simple forms of Captcha are easily defeated by robots, so this is an essential step to beef up your spam protection.

Kalle Tolonen
July 12, 2022

Requirements

A working django-simple-captcha implementation
Being comfortable with Django & Python

Tested on Debian 11 & Apache2

Register your site @ Google reCAPTCHA

Go to https://www.google.com/recaptcha/admin/create.

127.0.0.1 is localhost, so that’s good for development. After you’re done with the registration, you need to add your keys (that you get after submitting the form) to settings.py.

#settings.py

RECAPTCHA_PUBLIC_KEY = 'site key goes here'
RECAPTCHA_PRIVATE_KEY = 'secret key goes here'

While you’re at settings, remove all references to django-simple-captcha.

Modifying requirements

Modify your requirements.txt and replace django-simple-captcha pkg with django-recaptcha.

#requirements.txt

django-recaptcha

Next, let’s Uninstall django-simple-captcha and install the altered requirements.

pip uninstall django-simple-captcha
pip install -r requirements.txt

Check settings.py

Make sure you still have ‘captcha’ in your apps.

#settings.py

INSTALLED_APPS = [
    'captcha',
]

After that you should run migrations just to be sure.

,/manage.py makemigrations
./manage.py migrate

Forms

To use this, you need to modify your form fields.

#forms.py

from django import forms
from captcha.fields import ReCaptchaField
from captcha.widgets import ReCaptchaV2Checkbox

class ContactForm(forms.Form):
    name = forms.CharField(max_length = 50)
    email = forms.EmailField(max_length = 150)
    message = forms.CharField(widget = forms.Textarea, max_length = 2000)
    captcha = ReCaptchaField(widget=ReCaptchaV2Checkbox)

Views & Templates

You don’t need to modify views or templates if you’ve been using django-simple-captcha - you can check those out here.