Pre-populate a Gravity Forms Dropdown field with AffiliateWP Affiliates

pre-populate-gf-dropdown-with-affiliates.php

<?php

// Add filters for Form ID 8
add_filter( 'gform_pre_render_8', 'populate_posts' );
add_filter( 'gform_pre_validation_8', 'populate_posts' );
add_filter( 'gform_pre_submission_filter_8', 'populate_posts' );
add_filter( 'gform_admin_pre_render_8', 'populate_posts' );
function populate_posts( $form ) {
  
  // Loop through each field searching for any "select" field with the class "populate-affs"
  foreach ( $form['fields'] as &$field ) {
    if ( $field->type != 'select' || strpos( $field->cssClass, 'populate-affs' ) === false ) {
      continue;
    }
    
    // Set arguments for an affiliates query
    $args = array (
      'number' => -1,
      'order' => 'ASC',
      'orderby' => 'name'
    );
    
    // Get Affiliates
    $affiliates = affiliate_wp()->affiliates->get_affiliates($args);
    
    // Set empty choices array
    $choices = array();    
    
    // Loop through Affiliates and assign text (label) and value for each
    foreach ($affiliates as $affiliate) {
      
      // Set Affiliate ID as a variable
      $affiliate_id = $affiliate->affiliate_id;
      
      // Set User ID as a variable
      $user_id = $affiliate->user_id;
      
      // Get User Object with User ID
      $user = get_user_by( 'id', $user_id );
      
      // Assign Users First Name as the option label
      // Assign Affiliate ID as the option value
      $choices[] = array(
        'text' => $user->first_name,
        'value' => $affiliate_id
        //'isSelected' => $post->ID == rgget('post_id')
      );
      
    }
    // update the Drop Down field placeholder
    $field->placeholder = 'Select a Sales Rep';
    $field->choices = $choices;
  }
  return $form;
}