Add fallback to load CRM.vars.omnipay if not loaded via html-header region

Author: mattwire

CRM/Core/Payment/OmnipayMultiProcessor.php

@@ -357,7 +357,13 @@ public function buildForm(&$form) {
         $jsVariables[$clientSideKey] = $this->_paymentProcessor[$key];
       }
     }
-    CRM_Core_Resources::singleton()->addVars('omnipay', $jsVariables);
+
+    \Civi::resources()->addVars('omnipay', $jsVariables);
+    // Assign to smarty so we can add via tpl for drupal webform / default processor on contribution page because addVars doesn't work in that context
+    //   until https://github.com/civicrm/civicrm-core/pull/18141 is merged
+    //   Then we can set 'billing-block' above and remove the assign/tpl
+    $form->assign('omnipayJSVars', $jsVariables);
+
     if (is_array($regions)) {
       foreach ($regions as $region => $additions) {
         foreach ($additions as $addition) {

Metadata/omnipay_PaypalRest.mgd.php

@@ -103,6 +103,7 @@
         //'billing-block-post' => [],
         'billing-block' => [
           ['markup' => '<div id="paypal-button-container" class="crm-paypal-buttons"></div>', 'name' => 'paypal_button', 'weight' => 400],
+          ['template' => E::path('templates/CRM/Omnipaymultiprocessor/Form/OmnipayResource.tpl'), 'region' => 'billing-block', 'weight' => -1],
           ['name' => 'paypal_script', 'weight' => 500, 'scriptUrl' => \Civi::resources()->addCacheCode(E::url('Metadata/js/omnipay_PaypalRest.js'))]
         ],
       ],

templates/CRM/Omnipaymultiprocessor/Form/OmnipayResource.tpl

@@ -0,0 +1,23 @@
+{*
+ +--------------------------------------------------------------------+
+ | Copyright CiviCRM LLC. All rights reserved.                        |
+ |                                                                    |
+ | This work is published under the GNU AGPLv3 license with some      |
+ | permitted exceptions and without any warranty. For full license    |
+ | and copyright information, see https://civicrm.org/licensing       |
+ +--------------------------------------------------------------------+
+*}
+{* Manually create the CRM.vars.omnipay here for cases where \Civi::resources()->addVars() does not work (eg. drupal webform_civicrm, contribution page paypal checkout is default *}
+{literal}
+<script type="text/javascript">
+  CRM.$(function($) {
+    $(document).ready(function() {
+      if (typeof CRM.vars.omnipay === 'undefined') {
+        var omnipay = {{/literal}{foreach from=$omnipayJSVars key=arrayKey item=arrayValue}{$arrayKey}:'{$arrayValue}',{/foreach}{literal}};
+        CRM.vars.omnipay = omnipay;
+        //console.log('added vars via tpl');
+      }
+    });
+  });
+</script>
+{/literal}