Validation to manage users

[pippuccio76]

Hi , how can i set a validation rule to insert user with unique email ?

[datamweb]

Shield has applied these rules in the registration form by default.

    'email' => [
        'label' => 'Auth.email',
        'rules' => [
            'required',
            'max_length[254]',
            'valid_email',
            'is_unique[auth_identities.secret]',
        ],
    ],

More info see https://shield.codeigniter.com/customization/validation_rules/#registration

But if you want to do this custom in a new controller, you can use the RegisterController.php. To read more, refer to CI4 Validation.