make buffer response contents available at initialisation time

Author: zefir-git

src/response/BufferResponse.ts

@@ -9,19 +9,23 @@ export abstract class BufferResponse<A> extends Response<A> {
     /**
      * Fetch the buffer to send in the response body.
      */
-    protected abstract readBuffer(): Uint8Array | Promise<Uint8Array>;
+    protected abstract readonly buffer: Uint8Array;
 
-    protected override async send(res: http.ServerResponse, req?: Request<A>): Promise<void> {
-        const buffer = await this.readBuffer();
+    public override allHeaders(res: http.ServerResponse, req?: Request<A>) {
+        const headers = super.allHeaders(res, req);
         if (req !== undefined) {
             if (res.chunkedEncoding) {
-                if (!this.headers.has("transfer-encoding"))
-                    this.headers.set("transfer-encoding", "chunked");
+                if (!headers.has("transfer-encoding"))
+                    headers.set("transfer-encoding", "chunked");
             }
-            else if (!this.headers.has("content-length"))
-                this.headers.set("content-length", buffer.byteLength.toString());
+            else if (!headers.has("content-length"))
+                headers.set("content-length", this.buffer.byteLength.toString());
         }
+        return headers;
+    }
+
+    protected override async send(res: http.ServerResponse, req?: Request<A>): Promise<void> {
         this.writeHead(res, req);
-        res.end(buffer);
+        res.end(this.buffer);
     }
 }

src/response/TextResponse.ts

@@ -1,13 +1,12 @@
+import http from "node:http";
+import {Request} from "../Request.js";
 import {BufferResponse} from "./BufferResponse.js";
 
 /**
  * An HTTP response with a plain text body.
  */
 export class TextResponse<A> extends BufferResponse<A> {
-    /**
-     * The plain text body of the response.
-     */
-    protected readonly text: string;
+    protected override readonly buffer: Uint8Array;
     private readonly encoder = new TextEncoder();
 
     /**
@@ -18,12 +17,13 @@ export class TextResponse<A> extends BufferResponse<A> {
      */
     public constructor(text: string, statusCode = 200, headers?: HeadersInit) {
         super(statusCode, headers);
-        this.text = text;
-        if (!this.headers.has("content-type"))
-            this.headers.set("content-type", "text/plain");
+        this.buffer = this.encoder.encode(text);
     }
 
-    public override readBuffer() {
-        return this.encoder.encode(this.text);
+    public override allHeaders(res: http.ServerResponse, req?: Request<A>): Headers {
+        const headers = super.allHeaders(res, req);
+        if (!headers.has("content-type"))
+            headers.set("content-type", "text/plain");
+        return headers;
     }
 }