[ADD] website: reCAPTCHA

task-3336129

closes odoo/documentation#4818

Signed-off-by: Xavier Platteau (xpl) <xpl@odoo.com>

content/applications/websites/website/configuration.rst

@@ -10,4 +10,5 @@ Configuration
    configuration/translate
    configuration/multi_website
    configuration/unsplash
+   configuration/recaptcha
    configuration/on-premise_geo-ip-installation

content/applications/websites/website/configuration/recaptcha.rst

@@ -0,0 +1,84 @@
+=====================
+reCAPTCHA v3 on forms
+=====================
+
+Google's reCAPTCHA protects website forms against spam and abuse. It attempts to distinguish between
+human and bot submissions.
+
+.. note::
+   reCAPTCHA v3 works in the background and does not interrupt visitors. However, if the check
+   fails, visitors cannot submit the form.
+
+.. seealso::
+   `Google's reCAPTCHA v3 guide <https://developers.google.com/recaptcha/docs/v3>`_
+
+Configuration
+=============
+
+On Google
+---------
+
+Open `the reCAPTCHA website registration page <https://www.google.com/recaptcha/admin/create>`_. Log
+in or create a Google account if necessary.
+
+On the website registration page:
+
+- Give the website a :guilabel:`Label`.
+- Leave the :guilabel:`reCAPTCHA type` on :guilabel:`Score based (v3)`.
+- Enter one or more :guilabel:`Domains` (e.g., *example.com* or *subdomain.example.com*).
+- Under :guilabel:`Google Cloud Platform`, a project is automatically selected if one was already
+  created with the logged-in Google account. If not, one is automatically created. Click
+  :guilabel:`Google Cloud Platform` to select a project yourself or rename the automatically created
+  project.
+- Agree to the terms of service.
+- Click :guilabel:`Submit`.
+
+.. image:: recaptcha/recaptcha-google-configuration.png
+   :alt: reCAPTCHA website registration example
+
+A new page with the generated keys is then displayed. Leave it open for convenience, as copying the
+keys to Odoo is required next.
+
+On Odoo
+-------
+
+- From the database dashboard, click :guilabel:`Settings`. Under :guilabel:`Integrations`, enable
+  :guilabel:`reCAPTCHA` if needed.
+
+  .. warning::
+     Do not disable the :guilabel:`reCAPTCHA` feature or uninstall the :guilabel:`Google reCAPTCHA
+     integration` module, as many other modules would also be removed.
+
+- Open the Google reCAPTCHA page, copy the :guilabel:`Site key`, and paste it into the
+  :guilabel:`Site Key` field in Odoo.
+- Open the Google reCAPTCHA page, copy the :guilabel:`Secret key`, and paste it into the
+  :guilabel:`Secret Key` field in Odoo.
+- Change the default :guilabel:`Minimum score` (`0.5`) if necessary, using a value between `1.0`
+  and `0.0`. The higher the threshold is, the more difficult it is to pass the reCAPTCHA, and vice
+  versa.
+- Click :guilabel:`Save`.
+
+All pages using the :guilabel:`Form`, :guilabel:`Newsletter Block`, and :guilabel:`Newsletter Popup`
+snippets on the website are now protected by reCAPTCHA.
+
+.. note::
+   - If the reCAPTCHA check fails, the following error message is displayed:
+
+     .. image:: recaptcha/recaptcha-error.png
+        :alt: Google reCAPTCHA verification error message
+
+   - reCAPTCHA v3 is free for up to `1 million assessments per month <https://developers.google.com/recaptcha/docs/faq#are-there-any-qps-or-daily-limits-on-my-use-of-recaptcha>`_.
+
+.. tip::
+   - Analytics and additional settings are available on `Google's reCAPTCHA administration page
+     <https://www.google.com/recaptcha/admin/>`_. For example, you can receive email alerts if
+     Google detects suspicious traffic on your website or view the percentage of suspicious
+     requests, which could help you determine the right minimum score.
+
+   - You can notify visitors that reCAPTCHA protects a form. To do so, open the website editor
+     and navigate to the form. Then, click somewhere on the form, and on the right sidebar's
+     :guilabel:`Customize` tab, toggle :guilabel:`Show reCAPTCHA Policy` found under the
+     :guilabel:`Form` section.
+
+   .. image:: recaptcha/recaptcha-policy.png
+      :alt: reCAPTCHA policy message displayed on a form