Add basic response factories and helpers

src/http/response/HTMLResponseFactory.ts

@@ -0,0 +1,19 @@
+import {ResponseFactory} from "./ResponseFactory";
+import {Request} from "../lifecycle/Request";
+
+export function html(value: string): HTMLResponseFactory {
+    return new HTMLResponseFactory(value)
+}
+
+export class HTMLResponseFactory extends ResponseFactory {
+    constructor(
+        public readonly value: string,
+    ) { super() }
+
+    public async write(request: Request) {
+        request = await super.write(request)
+        request.response.setHeader('Content-Type', 'text/html; charset=utf-8')
+        request.response.body = this.value
+        return request
+    }
+}