Add new configuration option to set default error transformer per schema

Author: johannessteu

Classes/Service/SchemaService.php

@@ -160,7 +160,12 @@ protected function getMergedSchemaFromConfigurations(array $configuration): Sche
 
         $executableSchemas = [];
 
-        $transforms = [new FlowErrorTransform()];
+        // Determine default error transformer
+        if (array_key_exists('errorTransform', $configuration) && ! empty($configuration['errorTransform']) && class_exists($configuration['errorTransform'])) {
+            $transforms = [new $configuration['errorTransform']()];
+        } else {
+            $transforms = [new FlowErrorTransform()];
+        }
 
         $options = [
             'typeDefs' => [],

Configuration/Settings.yaml

@@ -28,3 +28,4 @@ t3n:
 #        'logRequests': true  # if enabled all requests are logged
 #        'context:' 'Foo\Vendor\GraphQL\Context  # optional context that overrides the global context
 #        'schemaEnvelope': 'Some\Fully\Qualified\Namespace'
+#        'errorTransform': t3n\GraphQL\Transform\FlowErrorTransform # optional: override the default error transformer for this schema