diff --git a/djblets/recaptcha/__init__.py b/djblets/recaptcha/__init__.py
new file mode 100644
index 0000000000000000000000000000000000000000..867fa5ce93df88a87d647c474fdf2f8907e355b5
--- /dev/null
+++ b/djblets/recaptcha/__init__.py
@@ -0,0 +1,4 @@
+from __future__ import unicode_literals
+
+
+default_app_config = 'djblets.recaptcha.apps.RecaptchaAppConfig'
diff --git a/djblets/recaptcha/apps.py b/djblets/recaptcha/apps.py
new file mode 100644
index 0000000000000000000000000000000000000000..dc8efc6a7309071afab3433d9b204f0f70fdd561
--- /dev/null
+++ b/djblets/recaptcha/apps.py
@@ -0,0 +1,12 @@
+from __future__ import unicode_literals
+
+try:
+ from django.apps import AppConfig
+except ImportError:
+ # Django < 1.7
+ AppConfig = object
+
+
+class RecaptchaAppConfig(AppConfig):
+ name = 'djblets.recaptcha'
+ label = 'djblets_recaptcha'
diff --git a/djblets/recaptcha/mixins.py b/djblets/recaptcha/mixins.py
new file mode 100644
index 0000000000000000000000000000000000000000..cb727870dede7131ecd1e25ef689091c765c8920
--- /dev/null
+++ b/djblets/recaptcha/mixins.py
@@ -0,0 +1,104 @@
+"""Mixins for providing reCAPTCHA validation support in forms.
+
+See :ref:`using-recaptcha` for a guide on using reCAPTCHA validation.
+"""
+
+from __future__ import unicode_literals
+
+import json
+import logging
+
+from django import forms
+from django.conf import settings
+from django.core.exceptions import ValidationError
+from django.utils.six.moves.urllib.error import URLError
+from django.utils.six.moves.urllib.parse import urlencode
+from django.utils.six.moves.urllib.request import urlopen
+from django.utils.translation import ugettext as _
+
+from djblets.recaptcha.widgets import RecaptchaWidget
+
+
+class RecaptchaFormMixin(forms.Form):
+ """A form mixin for providing reCAPTCHA verification.
+
+ If other mixins are used, this should be the first in the list of base
+ classes to ensure the reCAPTCHA field is the last.
+ """
+
+ def __init__(self, request, *args, **kwargs):
+ """Initialize the mixin.
+
+ Args:
+ request (django.http.HttpRequest):
+ The current HTTP request.
+
+ *args (tuple):
+ Additional positional arguments to pass to the superclass
+ constructor.
+
+ **kwargs (dict):
+ Additional keyword arguments to pass to the superclass
+ constructor.
+ """
+ super(RecaptchaFormMixin, self).__init__(*args, **kwargs)
+ self.fields['g-recaptcha-response'] = forms.CharField(
+ required=True,
+ widget=RecaptchaWidget)
+
+ @property
+ def verify_recaptcha(self):
+ """Whether or not the reCAPTCHA is to be verified.
+
+ Returns:
+ bool: Whether or not the reCAPTCHA is to be verified.
+ """
+ return True
+
+ def clean(self):
+ if self.verify_recaptcha:
+ data = urlencode({
+ 'secret': settings.RECAPTCHA_PRIVATE_KEY,
+ 'response': self.cleaned_data['g-recaptcha-response'],
+ 'remote-ip': self.request.META.get('REMOTE_ADDR'),
+ })
+
+ try:
+ resp = urlopen(
+ 'https://www.google.com/recaptcha/api/siteverify',
+ data)
+
+ payload = resp.read()
+ except URLError as e:
+ logging.exception('Could not make reCAPTCHA request: HTTP %s: '
+ '%s',
+ e.code, e.read())
+ raise ValidationError([
+ _('Could not validate reCAPTCHA. Please contact an '
+ 'administrator.'),
+ ])
+
+ try:
+ payload = json.loads(payload)
+ except ValueError:
+ logging.exception('Could not parse JSON payload from %r',
+ payload)
+ raise ValidationError([
+ _('Could not validate reCAPTCHA. Please contact an '
+ 'administrator.'),
+ ])
+
+ try:
+ if not payload['success']:
+ raise ValidationError([
+ _('Invalid reCAPTCHA response.'),
+ ])
+ except KeyError:
+ logging.exception('No "success" key in reCAPTCHA payload %r',
+ payload)
+ raise ValidationError([
+ _('Could not validate reCAPTCHA. Please contact an '
+ 'administrator.'),
+ ])
+
+ return super(RecaptchaFormMixin, self).clean()
diff --git a/djblets/recaptcha/siteconfig.py b/djblets/recaptcha/siteconfig.py
new file mode 100644
index 0000000000000000000000000000000000000000..9847f1146af2987e91a3ccc0bbc7922520974a73
--- /dev/null
+++ b/djblets/recaptcha/siteconfig.py
@@ -0,0 +1,13 @@
+from __future__ import unicode_literals
+
+
+settings_map = {
+ 'recaptcha_private_key': 'RECAPTCHA_PRIVATE_KEY',
+ 'recaptcha_public_key': 'RECAPTCHA_PUBLIC_KEY',
+}
+
+
+defaults = {
+ 'recaptcha_private_key': None,
+ 'recaptcha_public_key': None,
+}
diff --git a/djblets/recaptcha/templatetags/__init__.py b/djblets/recaptcha/templatetags/__init__.py
new file mode 100644
index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
diff --git a/djblets/recaptcha/templatetags/djblets_recaptcha.py b/djblets/recaptcha/templatetags/djblets_recaptcha.py
new file mode 100644
index 0000000000000000000000000000000000000000..b10b6103d2f6c0896f92750f4994228b5628953c
--- /dev/null
+++ b/djblets/recaptcha/templatetags/djblets_recaptcha.py
@@ -0,0 +1,37 @@
+from __future__ import unicode_literals
+
+from django import template
+from django.utils.html import mark_safe
+
+
+register = template.Library()
+
+
+@register.simple_tag
+def recaptcha_js():
+ """Render the reCAPTCHA JavaScript tag.
+
+ Returns:
+ django.utils.safestring.SafeText:
+ The rendered tag.
+ """
+ return mark_safe('')
+
+
+@register.simple_tag
+def recaptcha_form_field(form):
+ """Return the reCAPTCHA field from the specified form.
+
+ This can be used to render the reCAPTCHA widget.
+
+ Args:
+ form (django.forms.forms.Form):
+ The form that is being rendered.
+
+ Returns:
+ django.forms.boundfield.BoundField:
+ The bound reCAPTCHA field. This will render as its widget in a
+ template.
+ """
+ return form['g-recaptcha-response']
diff --git a/djblets/recaptcha/widgets.py b/djblets/recaptcha/widgets.py
new file mode 100644
index 0000000000000000000000000000000000000000..021edb47d1be4d50126049aae9b1ee83d9ffdab0
--- /dev/null
+++ b/djblets/recaptcha/widgets.py
@@ -0,0 +1,27 @@
+from __future__ import unicode_literals
+
+from django.conf import settings
+from django.forms import widgets
+from django.utils.html import format_html
+
+
+class RecaptchaWidget(widgets.Widget):
+ """A widget for rendering the reCAPTCHA form field."""
+
+ def render(self, *args, **kwargs):
+ """Render the reCAPTCHA form field.
+
+ Args:
+ *args (tuple):
+ Unused positional arguments.
+
+ **kwargs (dict):
+ Unused keyword arguments.
+
+ Returns:
+ django.utils.safestring.SafeText:
+ The rendered reCAPTCHA widget.
+ """
+ return format_html(
+ '',
+ settings.RECAPTCHA_PUBLIC_KEY)
diff --git a/docs/djblets/coderef/index.rst b/docs/djblets/coderef/index.rst
index 8f09236ebb0f7f396638534302d471d8dbd385fb..9f2673b842c1f42c4eda9ab14e4f19a58946915b 100644
--- a/docs/djblets/coderef/index.rst
+++ b/docs/djblets/coderef/index.rst
@@ -159,6 +159,17 @@ Markdown Utilities and Extensions
djblets.markdown.extensions.wysiwyg_email
+reCAPTCHA
+=========
+
+.. autosummary::
+ :toctree: python
+
+ djblets.recaptcha.mixins
+ djblets.recaptcha.templatetags.djblets_recaptcha
+ djblets.recaptcha.widgets
+
+
Registries
==========
diff --git a/docs/djblets/guides/index.rst b/docs/djblets/guides/index.rst
index 5e1587ab920c56bd7714d2709bfc1a3b94dd8e52..180f678dad3289cf40a37fcedc0d228ca46b445b 100644
--- a/docs/djblets/guides/index.rst
+++ b/docs/djblets/guides/index.rst
@@ -6,5 +6,6 @@ Guides
:maxdepth: 2
extensions/index
+ recaptcha/index
registries/index
webapi/index
diff --git a/docs/djblets/guides/recaptcha/index.rst b/docs/djblets/guides/recaptcha/index.rst
new file mode 100644
index 0000000000000000000000000000000000000000..178527b3b57212db3ab6dee5c98bc0bb63c4234f
--- /dev/null
+++ b/docs/djblets/guides/recaptcha/index.rst
@@ -0,0 +1,8 @@
+================
+reCAPTCHA Guides
+================
+
+.. toctree::
+ :maxdepth: 2
+
+ using-recaptcha
diff --git a/docs/djblets/guides/recaptcha/using-recaptcha.rst b/docs/djblets/guides/recaptcha/using-recaptcha.rst
new file mode 100644
index 0000000000000000000000000000000000000000..cf87610478b715b4f19090d578914d163799e5d4
--- /dev/null
+++ b/docs/djblets/guides/recaptcha/using-recaptcha.rst
@@ -0,0 +1,165 @@
+.. _using-recaptcha:
+
+===============
+Using reCAPTCHA
+===============
+
+.. currentmodule:: djblets.recaptcha
+
+
+Using reCAPTCHA validation in forms requires valid reCAPTCHA secret and site
+keys. You can get keys from https://www.google.com/recaptcha/.
+
+The keys can be stored in either Django settings or
+:py:mod:`site configuration settings `. The keys for
+Django settings are:
+
+* ``RECAPTCHA_PUBLIC_KEY``
+* ``RECPATCHA_PRIVATE_KEY``
+
+The equivalent site configuration keys are:
+
+* ``recaptcha_public_key``
+* ``recaptcha_private_key``
+
+
+reCAPTCHA in Forms
+------------------
+
+If you want to use reCAPTCHA in a form, that form will have to inherit from the
+:py:class:`~mixins.RecaptchaFormMixin` (as well as
+:py:class:`~django.forms.Form`).
+Your form can optionally provide a property,
+:py:meth:`~mixins.RecaptchaFormMixin.verify_recaptcha`, which will determine
+whether or not to validate the reCAPTCHA when the form is submitted. This can
+be used to optionally disable reCAPTCHA through a setting, for example.
+
+Your form will require special rendering to use reCAPTCHA. The
+:py:mod:`~djblets.recaptcha.templatetags.djblets_recaptcha` template tag
+library includes two template tags to help with this:
+
+* :py:meth:`~templatetags.djblets_recaptcha.recaptcha_js`, which renders the
+ necessary JavaScript to use reCAPTCHA on the page. This should be included
+ in the ```` of your document.
+
+* :py:meth:`~templatetags.djblets_recaptcha.recaptcha_form_field`, which
+ renders the actual reCAPTCHA field. This should be included in your form,
+ before the ```` tag.
+
+
+Using Site Configuration
+------------------------
+
+To use site configuration settings instead of Django settings, you will have to
+load the settings map for this module. This should happen once your app is
+initialized. An example using an :py:class:`django.apps.AppConfig` follows:
+
+.. code-block:: python
+
+ from django.apps import AppConfig
+ from djblets.siteconfig.django_settings import (apply_django_settings,
+ generate_defaults,
+ get_django_defaults,
+ get_django_settings_map)
+ from djblets.recaptcha import (defaults as recaptcha_defaults,
+ settings_map as recaptcha_settings_map)
+
+ class MyAppConfig(AppConfig):
+ def ready(self):
+ if not siteconfig.get_defaults():
+ defaults = get_django_defaults()
+ defaults.update(recaptcha_defaults)
+
+ siteconfig.add_defaults(defaults)
+
+ settings_map = get_django_settings_map()
+ settings_map.update(recaptcha_settings_map)
+
+ apply_django_settings(settings_map)
+
+
+Using reCAPTCHA in a Form Template
+----------------------------------
+
+If you are not using customized form rendering (i.e. you are rendering your
+form as ``{{form}}`` in your template, you can continue to do so; just ensure
+that the :py:meth:`~templatetags.djblets_recaptcha.recaptcha_js` template tag
+appears in the document ````. However, if you are rendering your form
+fields individually, you will have to use the
+:py:meth:`~templatetags.djblets_recaptcha.recaptcha_form_field` template tag.
+
+For example, consider the following form:
+
+.. code-block:: python
+
+ from django import forms
+ from django.forms import fields
+ from djblets.recaptcha.mixins import RecaptchaFormMixin
+
+
+ class RegistrationForm(RecaptchaFormMixin, forms.Form):
+ username = fields.CharField(max_length=32,
+ label='Username')
+ password = fields.CharField(min_length=8,
+ label='Password',
+ widget=forms.PasswordInput)
+
+The following two templates can be used to render the form, assuming ``form``
+is the instance of the form. The first template shows rendering using Django's
+built-in form rendering:
+
+.. code-block:: html
+
+ {% load djblets_recaptcha %}
+
+
+
+
+ Register
+ {% recaptcha_js %}
+
+
+ {{form}}
+
+
+
+The second example shows how to use direct field rendering:
+
+.. code-block:: html
+
+ {% load djblets_recaptcha %}
+
+
+
+
+ Register
+ {% recaptcha_js %}
+
+
+
+
+
+
+
+Styling reCAPTCHA fields
+------------------------
+
+The reCAPTCHA field will render as a ``
`` element with the class
+``g-recaptcha`` if you wish to style it.