fix typing issue

Author: conico974

packages/open-next/src/adapters/plugins/image-optimization/image-optimization.replacement.ts

@@ -4,9 +4,7 @@ import type { APIGatewayProxyEventHeaders } from "aws-lambda";
 import type { NextConfig } from "next/dist/server/config-shared";
 //#override imports
 import {
-  // @ts-ignore
   fetchExternalImage,
-  // @ts-ignore
   fetchInternalImage,
   imageOptimizer,
 } from "next/dist/server/image-optimizer";
@@ -32,13 +30,12 @@ export async function optimizeImage(
     ? await fetchExternalImage(href)
     : await fetchInternalImage(
         href,
-        // @ts-ignore
+        // @ts-expect-error - It is supposed to be an IncomingMessage object, but only the headers are used.
         { headers },
         {}, // res object is not necessary as it's not actually used.
         handleRequest,
       );
 
-  // @ts-ignore
   const result = await imageOptimizer(
     imageUpstream,
     imageParams,

packages/open-next/src/adapters/plugins/image-optimization/image-optimization.ts

@@ -21,13 +21,12 @@ export async function optimizeImage(
   ) => Promise<void>,
 ) {
   const result = await imageOptimizer(
-    // @ts-ignore
     { headers },
     {}, // res object is not necessary as it's not actually used.
     imageParams,
     nextConfig,
     false, // not in dev mode
-    // @ts-ignore
+    // @ts-expect-error - This file is used only for Next 14.1 and below. Typing is correct for these versions.
     handleRequest,
   );
   debug("optimized result", result);

packages/open-next/src/http/openNextResponse.ts

@@ -25,7 +25,6 @@ export interface StreamCreator {
 }
 
 // We only need to implement the methods that are used by next.js
-// @ts-ignore
 export class OpenNextNodeResponse extends Transform implements ServerResponse {
   statusCode!: number;
   statusMessage: string = "";
@@ -324,6 +323,18 @@ export class OpenNextNodeResponse extends Transform implements ServerResponse {
     callback();
   }
 
+  /**
+   * New method in Node 18.15+
+   * There are probably not used right now in Next.js, but better be safe than sorry
+   */
+
+  setHeaders(headers: Headers | Map<string, number | string | readonly string[]>): this {
+    headers.forEach((value, key) => {
+      this.setHeader(key, Array.isArray(value) ? value : value.toString());
+    })
+    return this;
+  }
+
   /**
    * Next specific methods
    * On earlier versions of next.js, those methods are mandatory to make everything work