Method handleRendering

packages/angular/ssr/src/app.ts:279–377

* Handles the server-side rendering process for the given HTTP request. * This method matches the request URL to a route and performs rendering if a matching route is found. * * @param request - The incoming HTTP request to be processed. * @param matchedRoute - The metadata of the matche

(
    request: Request,
    matchedRoute: RouteTreeNodeMetadata,
    requestContext?: unknown,
  )

   * @returns A promise that resolves to the rendered response, or null if no matching route is found.
   */
  private async handleRendering(
    request: Request,
    matchedRoute: RouteTreeNodeMetadata,
    requestContext?: unknown,
  ): Promise<Response | null> {
    const { renderMode, headers, status, preload } = matchedRoute;

    if (!this.allowStaticRouteRender && renderMode === RenderMode.Prerender) {
      return null;
    }

    const url = new URL(request.url);
    const platformProviders: StaticProvider[] = [];

    const {
      manifest: { bootstrap, locale },
      assets,
    } = this;

    // Initialize the response with status and headers if available.
    const responseInit = {
      status,
      headers: new Headers({
        'Content-Type': 'text/html;charset=UTF-8',
        ...(locale !== undefined ? { 'Content-Language': locale } : {}),
        ...headers,
      }),
    };

    if (renderMode === RenderMode.Server) {
      // Configure platform providers for request and response only for SSR.
      platformProviders.push(
        {
          provide: REQUEST,
          useValue: request,
        },
        {
          provide: REQUEST_CONTEXT,
          useValue: requestContext,
        },
        {
          provide: RESPONSE_INIT,
          useValue: responseInit,
        },
      );
    } else if (renderMode === RenderMode.Client) {
      // Serve the client-side rendered version if the route is configured for CSR.
      let html = await this.assets.getServerAsset('index.csr.html').text();
      html = await this.runTransformsOnHtml(html, url, preload);

      return new Response(html, responseInit);
    }

    if (locale !== undefined) {
      platformProviders.push({
        provide: LOCALE_ID,
        useValue: locale,
      });