User registration functions to sign up agency staff. Place all functions in functions.php of the hubs' theme.

register.php

<?php 
function is_valid_email_domain($login, $email, $errors ){
    $valid_email_domains = array("ocre.com.au","stafflink.com.au");// whitelist email domain lists
    $valid = false;
    foreach( $valid_email_domains as $d ){
    $d_length = strlen( $d );
    $current_email_domain = strtolower( substr( $email, -($d_length), $d_length));
    if( $current_email_domain == strtolower($d) ){
    $valid = true;
    break;
    }
    }
    // if invalid, return error message
    if( $valid === false ){
    $errors->add('domain_whitelist_error',__( '<strong>ERROR</strong>: Sorry, your email address is not on the approved list. You must use a valid Ouwens Casserly email address.' ));
    }
   }
   add_action('register_post', 'is_valid_email_domain',10,3 );
  
  
  
   // output the form field
   add_action('register_form', 'ad_register_fields');
   function ad_register_fields() {
   ?>
       <p>
           <label for="firstname"><?php _e('First Name') ?><br />
           <input type="firstname" name="firstname" id="firstname" class="input" value="<?php echo esc_attr($_POST['firstname']); ?>" size="25" tabindex="20" />
           </label>
       </p>
   <?php
   }
   
// save new first name
add_filter('pre_user_first_name', 'add_user_firstname');

function add_user_firstname($firstname) {
    if (isset($_POST['firstname'])) {
        $firstname = $_POST['firstname'];
    }
    return $firstname;
}
  
  
add_filter( 'gform_user_registration_prepared_value', 'serialize_user_type', 10, 5 );

function serialize_user_type($value, $field, $input_id, $entry, $is_username ) {
    if ( $field->id == '7' && $field->type == 'select' ) {
        // if ($value == 'property_manager') { // This method works.
        //     $value = [$value]; // this needs ot happen for it to store correctly. Not sure who to point the finger at here.
        // }
            $value = [$value]; // this needs ot happen for it to store correctly. Not sure who to point the finger at here.
    }
	return $value;
}
  
add_action( 'gform_user_registered', 'update_user_groups', 10, 4 );
// Add user to LearnDash Group if purchases specific WooCommerce product
function update_user_groups( $user_id, $feed, $entry, $user_pass ) {
    // Add group ID from LearnDash here
    $ld_group_id = 1658;
    ld_update_group_access( $user_id, $ld_group_id, false );
}
  
  /**
   * Bypass Force Login to allow for exceptions. Used to push everyone to the login page, except if they are registering.
   *
   * @param bool $bypass Whether to disable Force Login. Default false.
   * @param string $visited_url The visited URL.
   * @return bool
   */
  function my_forcelogin_bypass( $bypass, $visited_url ) {
      // Allow all single posts
      if ( is_single() ) {
        $bypass = true;
      }
    
      // Allow these absolute URLs
      $allowed = array(
        home_url( '/register/' )
      );
      if ( ! $bypass ) {
        $bypass = in_array( $visited_url, $allowed );
      }
    
      return $bypass;
    }
    add_filter( 'v_forcelogin_bypass', 'my_forcelogin_bypass', 10, 2 );
  
  
/*
 * Gravity Wiz // Gravity Forms // Email Domain Validator // Used by STAFFLINK on the Gravity Forms user rego form.
 *
 * This snippets allows you to exclude a list of invalid domains or include a list of valid domains for your Gravity Form Email fields.
 *
 * @version   1.4
 * @author    David Smith <david@gravitywiz.com>
 * @license   GPL-2.0+
 * @link      http://gravitywiz.com/banlimit-email-domains-for-gravity-form-email-fields/
*/
class GW_Email_Domain_Validator {
  
    private $_args;
  
    function __construct($args) {
  
    	$this->_args = wp_parse_args( $args, [
    	    'form_id' => false,
    	    'field_id' => false,
    	    'domains' => false,
    	    'validation_message' => __( 'Sorry, <strong>%s</strong> email accounts are not eligible for this form.' ),
    	    'mode' => 'ban' // also accepts "limit"
		] );
  
        // convert field ID to an array for consistency, it can be passed as an array or a single ID
        if($this->_args['field_id'] && !is_array($this->_args['field_id']))
        	$this->_args['field_id'] = array($this->_args['field_id']);

        	$form_filter = $this->_args['form_id'] ? "_{$this->_args['form_id']}" : '';

        add_filter("gform_validation{$form_filter}", array($this, 'validate'));
  
    }
  
    function validate($validation_result) {
  
        $form = $validation_result['form'];
  
        foreach($form['fields'] as &$field) {
  
            // if this is not an email field, skip
            if(RGFormsModel::get_input_type($field) != 'email')
                continue;
  
            // if field ID was passed and current field is not in that array, skip
            if($this->_args['field_id'] && !in_array($field['id'], $this->_args['field_id']))
                continue;
  
            $page_number = GFFormDisplay::get_source_page( $form['id'] );
            if( $page_number > 0 && $field->pageNumber != $page_number ) {
                continue;
            }
  
            if( GFFormsModel::is_field_hidden( $form, $field, array() ) ) {
                continue;
            }
  
            $domain = $this->get_email_domain($field);
  
            // if domain is valid OR if the email field is empty, skip
            if($this->is_domain_valid($domain) || empty($domain))
                continue;
  
            $validation_result['is_valid'] = false;
            $field['failed_validation'] = true;
            $field['validation_message'] = sprintf($this->_args['validation_message'], $domain);
  
        }
  
        $validation_result['form'] = $form;
        return $validation_result;
    }
  
    function get_email_domain( $field ) {
        $email = explode( '@', rgpost( "input_{$field['id']}" ) );
        return trim( rgar( $email, 1 ) );
    }
  
    function is_domain_valid( $domain ) {
  
        $mode   = $this->_args['mode'];
        $domain = strtolower( $domain );
  
        foreach( $this->_args['domains'] as $_domain ) {
  
            $_domain = strtolower( $_domain );
            $full_match   = $domain == $_domain;
            $suffix_match = strpos( $_domain, '.' ) === 0 && $this->str_ends_with( $domain, $_domain );
            $has_match    = $full_match || $suffix_match;
  
            if( $mode == 'ban' && $has_match ) {
                return false;
            } else if( $mode == 'limit' && $has_match ) {
                return true;
            }
  
        }
  
        return $mode == 'limit' ? false : true;
    }
  
    function str_ends_with( $string, $text ) {
  
        $length      = strlen( $string );
        $text_length = strlen( $text );
  
        if( $text_length > $length ) {
            return false;
        }
  
        return substr_compare( $string, $text, $length - $text_length, $text_length ) === 0;
    }
  
}
  
/*
 * Valid email addresses and options for validation.
*/ 
class GWEmailDomainControl extends GW_Email_Domain_Validator { }

new GW_Email_Domain_Validator( [
    'form_id' => 1,
    'field_id' => 2,
    'domains' => ['ocre.com.au', 'stafflink.com.au'],
    'validation_message' => __( 'Sorry! <strong>%s</strong> email accounts are not eligible for this form. Please use a valid email address.' ),
    'mode' => 'limit'
] );