Use createRequire for template modules (#1379)

* Use Node module namespace to expose require

* Add changeset for synchronous template require

Author: smorimoto

.changeset/synchronous-template-require.md

@@ -0,0 +1,6 @@
+---
+"swagger-typescript-api": patch
+---
+
+Support synchronous require in templates using Node's createRequire.
+

src/templates-worker.ts

@@ -1,3 +1,4 @@
+import * as module from "node:module";
 import * as path from "node:path";
 import * as url from "node:url";
 import { consola } from "consola";
@@ -7,6 +8,8 @@ import type { CodeGenProcess } from "./code-gen-process.js";
 import type { CodeGenConfig } from "./configuration.js";
 import type { FileSystem } from "./util/file-system.js";
 
+const require = module.createRequire(import.meta.url);
+
 export class TemplatesWorker {
   config: CodeGenConfig;
   fileSystem: FileSystem;
@@ -74,21 +77,21 @@ export class TemplatesWorker {
     );
   };
 
-  requireFnFromTemplate = async (packageOrPath: string) => {
+  requireFnFromTemplate = (packageOrPath: string) => {
     const isPath =
       packageOrPath.startsWith("./") || packageOrPath.startsWith("../");
 
     if (isPath) {
-      return await import(
+      return require(
         path.resolve(
           this.config.templatePaths.custom ||
             this.config.templatePaths.original,
           packageOrPath,
-        )
+        ),
       );
     }
 
-    return await import(packageOrPath);
+    return require(packageOrPath);
   };
 
   getTemplate = (name: string, fileName: string, path?: string) => {