From 2d81ca569d824be47706b059912bdfb9d68545bc Mon Sep 17 00:00:00 2001
From: William Cheng <wing328hk@gmail.com>
Date: Tue, 12 Sep 2023 14:17:04 +0800
Subject: [PATCH] better null check for schema types

---
 .../java/org/openapitools/codegen/OpenAPINormalizer.java   | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/OpenAPINormalizer.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/OpenAPINormalizer.java
index 9a51066c7b46..ebe004e8fe58 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/OpenAPINormalizer.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/OpenAPINormalizer.java
@@ -153,7 +153,7 @@ public void processRules(Map<String, String> inputRules) {
 
         // loop through all the rules
         for (Map.Entry<String, String> rule : inputRules.entrySet()) {
-            LOGGER.info("processing rule {} => {}", rule.getKey(), rule.getValue());
+            LOGGER.debug("processing rule {} => {}", rule.getKey(), rule.getValue());
             if (!ruleNames.contains(rule.getKey())) { // invalid rule name
                 LOGGER.warn("Invalid openapi-normalizer rule name: ", rule.getKey());
             } else if (enableAll) {
@@ -882,6 +882,11 @@ private Schema processNormalize31Spec(Schema schema, Set<Schema> visitedSchemas)
         if (!getRule(NORMALIZE_31SPEC)) {
             return schema;
         }
+
+        if (schema == null || schema.getTypes() == null) {
+            return null;
+        }
+
         // process null
         if (schema.getTypes().contains("null")) {
             schema.setNullable(true);