Save Authorize.net transaction id to gravity forms field after completed payment and include the new data in the Zapier feed

transaction.php

/***
* Add transaction ID to forms with this field after a payment is processed
***/

add_action( 'gform_post_payment_action', 'save_transaction_id', 10, 2);
function save_transaction_id( $entry, $action ) {
    $id = rgar( $entry, 'id');
    $trans_id = rgar( $action, 'transaction_id' );
    $trans_form_id = rgar( $entry, 'form_id');
    $trans_field_id = '';

    $form = GFAPI::get_form( $trans_form_id );
    foreach( $form['fields'] as $field ) {
      if($field->label == 'Transaction ID'){
        $trans_field_id = $field->id;
      }
    }
    GFAPI::update_entry_field( $id, $trans_field_id, $trans_id );

}

/***
* Add transaction field data to Zapier feed
***/
add_filter( 'gform_zapier_field_value', 'format_entry_value', 10, 4 );
function format_entry_value( $value, $form_id, $field_id, $entry ) {

$form = GFAPI::get_form( $form_id );
    foreach( $form['fields'] as $field ) {
      if($field->label == 'Transaction ID'){
        $trans_field_id = $field->id;
      }
    }

if ( $field_id == $trans_field_id ) {
$entry = GFAPI::get_entry( $entry['id'] );
$value = rgar( $entry, $trans_field_id );
}

return $value;
}