flow like the river

BACK_BACK/node_modules/graphql/validation/rules/custom/NoSchemaIntrospectionCustomRule.mjs

@@ -0,0 +1,25 @@
+import { GraphQLError } from "../../../error/GraphQLError.mjs";
+import { getNamedType } from "../../../type/definition.mjs";
+import { isIntrospectionType } from "../../../type/introspection.mjs";
+
+/**
+ * Prohibit introspection queries
+ *
+ * A GraphQL document is only valid if all fields selected are not fields that
+ * return an introspection type.
+ *
+ * Note: This rule is optional and is not part of the Validation section of the
+ * GraphQL Specification. This rule effectively disables introspection, which
+ * does not reflect best practices and should only be done if absolutely necessary.
+ */
+export function NoSchemaIntrospectionCustomRule(context) {
+  return {
+    Field: function Field(node) {
+      var type = getNamedType(context.getType());
+
+      if (type && isIntrospectionType(type)) {
+        context.reportError(new GraphQLError("GraphQL introspection has been disabled, but the requested query contained the field \"".concat(node.name.value, "\"."), node));
+      }
+    }
+  };
+}