Backlight supports Google reCAPTCHA v2 Spam Protection. reCAPTCHA is a service provided by Google that adds a bot-detection component to forms. This typically presents the user with a checkbox that they are asked to tick to prove that they are not a robot. If the service detects that 'person' completing the form is likely a source of spam, then the checkbox is replaced with a more advanced interaction, such as needing to select all images that meet certain criteria.
Three steps are required to add reCAPTCHA to your contact forms:
You firstly need to be signed up with a Google account, such as you may use for email.
To register reCAPTCHA for your Google account, visit here. Give your registration a label, e.g. My Photography Site, select reCAPTCHA V2, and add any domains that you will be running your Backlight install with contact form, e.g. yoursite.com and anothersite.com. There is no need to also register subdomains, such as www or photography.yoursite.com.
To use reCAPTCHA on a test site running on your Mac or PC (e.g. via WAMP or LAMP), register an additional site with an entry for localhost or other locally-used domain.
Once registered, you will be presented with a Site Key and Secret Key. Copy and paste these into a text file, for usage within Backlight.
Backlight with Pages version 1.2 and newer includes a new Settings section titled Contact Forms Spam Protection. Log into Backlight and visit the page Backlight → Settings.
Set your Site Key and Secret Key as provided from the registration process, above.
The Validation Error Message setting lets you tweak the error message provided when submitting a contact form without having completed the reCAPTCHA section.
reCAPTCHA can be enabled and disabled for each Contact Form. To enable reCAPTCHA, visit Designer → Contact Forms and click edit for the form you wish to add reCAPTCHA to. Change the setting for Enable reCAPTCHA and click save.
Once enabled, the contact form should show a reCAPTCHA section above the Send button.
Backlight provides a setting to display error messages in the case that you find reCAPTCHA failing to accept a form submission when it should. To enable this setting, visit Backlight → Settings, scroll down to Contact Forms Spam Protection and enable the Debug reCAPTCHA option. If the resulting error message on form submission does not help solve the issue, then please ask for assistance on our forum.
Further information on Google's reCAPTCHA can be found here.