[go] Allow user overrides for generated outputs (#5132)

Author: jimschubert

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoGinServerCodegen.java

@@ -131,16 +131,30 @@ public void processOpts() {
             setPackageName((String) additionalProperties.get(CodegenConstants.PACKAGE_NAME));
         } else {
             setPackageName("openapi");
+            additionalProperties.put(CodegenConstants.PACKAGE_NAME, this.packageName);
         }
 
         /*
          * Additional Properties.  These values can be passed to the templates and
          * are available in models, apis, and supporting files
          */
-        additionalProperties.put("apiVersion", apiVersion);
-        additionalProperties.put("serverPort", serverPort);
-        additionalProperties.put("apiPath", apiPath);
-        additionalProperties.put(CodegenConstants.PACKAGE_NAME, packageName);
+        if (additionalProperties.containsKey("apiVersion")) {
+            this.apiVersion = (String)additionalProperties.get("apiVersion");
+        } else {
+            additionalProperties.put("apiVersion", apiVersion);
+        }
+
+        if (additionalProperties.containsKey("serverPort")) {
+            this.serverPort = Integer.parseInt((String)additionalProperties.get("serverPort"));
+        } else {
+            additionalProperties.put("serverPort", serverPort);
+        }
+
+        if (additionalProperties.containsKey("apiPath")) {
+            this.apiPath = (String)additionalProperties.get("apiPath");
+        } else {
+            additionalProperties.put("apiPath", apiPath);
+        }
 
         modelPackage = packageName;
         apiPackage = packageName;