refactor to use fulcrm_apiv2_prevent_loop

fulcrm_webhook.module

@@ -49,6 +49,9 @@ function fulcrm_webhook_webhook( $uuid ) {
             $payload_error_msg = json_last_error_msg();
         }
 
+        $client_id = variable_get( 'fulcrm_apiv2_client_id' );
+
+        if ( fulcrm_apiv2_prevent_loop( $headers ) ) {
             switch ( $method ) {
             case 'GET':
                 drupal_json_output( array( "status" => "error", "info" => "GET requests do nothing; webhooks must be POST, PATCH, PUT, or DELETE" ) );
@@ -58,13 +61,18 @@ function fulcrm_webhook_webhook( $uuid ) {
             case 'PATCH':
             case 'PUT':
                 if ( $payload === null ) {
-                // actually do something :)
                     drupal_json_output( array( 'status' => 'error', 'info' => $payload_error_msg ) );
                 } else {
+                    // actually do something :)
                     drupal_json_output( array( 'status' => 'ok', 'headers' => $headers, 'method' => $method ) );
                 }
                 break;
             default:
+                drupal_json_output( array( 'status' => 'error', 'info' => 'unsupported method' ) );
+                break;
+            }
+        } else {
+            drupal_json_output( array( 'status' => 'ok', 'info' => 'loop prevention' ) );
         }
     } else {
         drupal_access_denied();