The documentation says that if the facebook: {register: true} option is set on the sync gateway config, a new user will be created with the email as the user name, when first authenticating him.
What happens if the user did not grant email permission ? Will the user be created with another name ? Will it raise an error ?
The 1.1 release of Couchbase Mobile (Couchbase Lite and Sync Gateway) now uses the Facebook id as the user’s name property in SG.
The email is still required however so when integrating the Facebook SDK in your mobile app, you must specify the email permission for the authentication with SG to work.